Chemical and biochemical study of industrially produced San Simón da Costa smoked semi-hard cow's milk cheeses: Effects of storage under vacuum and different modified atmospheres.

PubMed

Garabal, J I; Rodríguez-Alonso, P; Franco, D; Centeno, J A

2010-05-01

Two batches of smoked, semi-hard (ripened for 45 d) San Simón da Costa cow's milk cheeses with Protected Designation of Origin were used to investigate the chemical, biochemical, and sensorial parameters that may be affected by modified-atmosphere packaging. Cheeses were packaged for 45 d as follows: vacuum packaging, packaging in 100% N(2), packaging in a gas mixture of 20% CO(2)/80% N(2), and packaging in a gas mixture of 50% CO(2)/50% N(2). The San Simón da Costa cheeses were characterized by high contents of lactic, oxalic, and citric organic acids. The main free amino acids found were isoleucine, phenylalanine, serine, valine, lysine, and glutamic acid, and the most abundant volatile compounds included ethanol, diacetyl, 2-butanol, isopropyl alcohol, furfural, acetaldehyde, 2-butanone, acetone, and 2-methylfuran. Modified atmospheres appeared to alter the ripening processes by affecting lipolysis, as indicated by the lower concentrations of butyric and propionic acids compared with control cheeses. In addition, modified-atmosphere packaging altered the proteolysis processes, yielding higher amounts of branched-chain alcohols. The results revealed that storage under modified atmosphere contributes to the accumulation of several compounds probably derived from smoke, including aldehydes such as 2-furancarboxaldehyde (furfural), alcohols such as 2-methoxyphenol (guaiacol), ketones such as 2-cyclopenten-1-one, and esters such as methyl furancarboxylate, which were negatively correlated with flavor. Vacuum packaging was the most useful technique in terms of preserving the sensory quality of San Simón da Costa Protected Designation of Origin cheeses. Considering the current demands for packaged portions of food at the distribution and retail levels and the potential health risks associated with some smoke-derived compounds usually present in some smoked foods, the results obtained in this study may be of special interest to the cheese industry. Copyright 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Combining an Analytic Hierarchy Process and TOPSIS for Selecting Postharvest Technology Method for Selayar Citrus in Indonesia

NASA Astrophysics Data System (ADS)

Dirpan, Andi

2018-05-01

This research was intended to select the best handling methods or postharvest technologies that can be used to maintain the quality of citrus fruit in Selayar, South Sulawesi, Indonesia among (1) modified atmosphere packaging (MAP (2) Controlled atmosphere storage (CAS) (3) coatings (4) hot water treatment (5) Hot Calcium Dip (HCD) by using combination between an analytic hierarchy process (AHP) and TOPSIS. Improving quality, applicability, increasing shelf life and reducing cost are used as the criteria to determine the best postharvest technologies. The results show that the most important criteria for selecting postharvest technology is improving quality followed by increasing shelf life, reducing cost and applicability. Furthermore, by using TOPSIS, it is clear that the postharvest technology that had the lowest rangking is modified atmosphere packaging (MAP), followed by controlled atmosphere storage (CAS), coatings, hot calcium dip (HCD) and hot water treatment (HWT). Therefore, it can be concluded that the best postharvest technology method for Selayar citrus is modified atmosphere packaging (MAP).

Spoilage and safety characteristics of ground beef packaged in traditional and modified atmosphere packages.

PubMed

Brooks, J C; Alvarado, M; Stephens, T P; Kellermeier, J D; Tittor, A W; Miller, M F; Brashears, M M

2008-02-01

Two separate studies, one with pathogen-inoculated product and one with noninoculated product, were conducted to determine the safety and spoilage characteristics of modified atmosphere packaging (MAP) and traditional packaging of ground beef patties. Ground beef patties were allotted to five packaging treatments (i) control (foam tray with film overwrap; traditional), (ii) high-oxygen MAP (80% 02, 20% CO2), (iii) high-oxygen MAP with added rosemary extract, (iv) low-oxygen carbon monoxide MAP (0.4% CO, 30% CO2, 69.6% N2), and (v) low-oxygen carbon monoxide MAP with added rosemary extract. Beef patties were evaluated for changes over time (0, 1, 3, 5, 7, 14, and 21 days) during lighted display. Results indicated low-oxygen carbon monoxide gas flush had a stabilizing effect on meat color after the formation of carboxymyoglobin and was effective for preventing the development of surface discoloration. Consumers indicated that beef patties packaged in atmospheres containing carbon monoxide were more likely to smell fresh at 7, 14, and 21 days of display, but the majority would probably not consume these products after 14 days of display because of their odor. MAP suppressed the growth of psychrophilic aerobic bacteria when compared with control packages. Generally, control packages had significantly higher total aerobic bacteria and Lactobacillus counts than did modified atmosphere packages. In the inoculated ground beef (approximately 10(5) CFU/g) in MAP, Escherichia coli O157 populations ranged from 4.51 to 4.73 log CFU/g with no differences among the various packages, but the total E. coli O157:H7 in the ground beef in the control packages was significantly higher at 5.61 log CFU/g after 21 days of storage. On days 14 and 21, the total Salmonella in the ground beef in control packages was at 5.29 and 5.27 log CFU/g, respectively, which was significantly higher than counts in the modified atmosphere packages (3.99 to 4.31 log CFU/g on day 14 and 3.76 to 4.02 log CFU/g on day 21). Data from these studies indicate that MAP suppresses pathogen growth compared with controls and that spoilage characteristics developed in MAP packages.

Comparison of modified atmosphere packaging and vacuum packaging for long period storage of dry-cured ham: effects on colour, texture and microbiological quality.

PubMed

García-Esteban, Marta; Ansorena, Diana; Astiasarán, Iciar

2004-05-01

Slices of dry-cured hams (Biceps femoris muscle) were stored during 8 weeks under vacuum and modified atmospheres (100% N(2) and a mixture of 20% CO(2) and 80% N(2)) in order to study the modifications on colour, texture and microbial counts during that period. Lightness was found to be more stable when samples were stored with 20% CO(2) and 80% N(2) without statistical differences between vacuum and 100% N(2). A slight whiteness was observed in the vacuum packed samples. Yellowness increased during time in vacuum packed samples, although no differences were found among the three conditions at the end of the study. Redness values were not affected by time or by the packaging system. With regard to texture, values found for all samples were within the normal range for this type of products, although it was observed that modified atmosphere packaging preserved samples better from hardening than vacuum packaging. No safety problems were detected in relation to the microbial quality in any case. In general, no clear differences were found among the three packaging systems for colour, texture and microbial quality in the storage conditions studied.

Nutritional quality changes throughout shelf-life of fresh-cut kailan-hybrid and 'Parthenon' broccoli as affected by temperature and atmosphere composition.

PubMed

Martínez-Hernández, Ginés Benito; Gómez, Perla A; Artés, Francisco; Artés-Hernández, Francisco

2015-01-01

The nutritional quality changes of the fresh-cut kailan-hybrid broccoli were compared with those of the 'Parthenon' cv. throughout 15 days at 2 ℃, 5 ℃ and 8 ℃ under air and modified atmosphere packaging. Florets showed higher dietary fiber content than stems. The total protein content of kailan-hybrid florets was 2.2-fold higher than that of 'Parthenon' cv. and higher amounts of S, Ca, Mg, Fe, Sr, Mn, Zn and Cu were found. However, 'Parthenon' florets registered higher initial total phenolics content than the kailan-hybrid edible part, followed by an increase throughout shelf-life favored at 5 ℃ and 8 ℃ under modified atmosphere packaging (5-7 kPa O2 + 14-15 kPa CO2). Modified atmosphere packaging stored samples at 8 ℃ showed higher individual phenolics content than modified atmosphere packaging stored samples at 2 ℃. The initial total antioxidant capacity of the kailan-hybrid edible part was higher than that of 'Parthenon' cv. florets. In conclusion, the kailan-hybrid florets generally showed healthier properties on the analyzed bioactive compounds, except total phenolic content, compared to the conventional 'Parthenon' cv. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Effect of storage temperature on the microbial composition of ready-to-use vegetables.

PubMed

Caldera, L; Franzetti, L

2014-02-01

Four different salad preparations were investigated from microbiological point of view: two were packaged in air and two under Modified Atmosphere. The samples were stored at 4 and 10 °C, and analysed at established times. Total bacterial count (TBC) was taken as the most relevant index to define their hygiene and quality at both temperatures. Lactic acid bacteria, yeasts and moulds were found only occasionally. In general, the most important factor was the packaging technique: TBC was lower when the product is packed under modified conditions. The packaging technique also influences the microbial population: Gram-negative aerobic rods are dominant in air-packaged products, whilst the presence of Enterobacteriaceae becomes important in salads packaged under Modified Atmosphere. Pseudomonas fluorescens, with all its biovars, was the most frequently found species amongst the aerobic isolates, whilst for the Enterobacteriaceae strains, there was no dominant species.

Changes of pH and peroxide value in carp (Cyprinus carpio) cuts packaged in modified atmosphere

NASA Astrophysics Data System (ADS)

Milijašević, M.; Babić Milijašević, J.; Đinović-Stojanović, J.; Vesković Moračanin, S.; Lilić, S.

2017-09-01

The aim of our research was to examine the influence of packaging in modified atmosphere on the pH and peroxide value in muscle of common carp (Cyprinus carpio), as well as to determine the most suitable gas mixtures for packing of that freshwater species. Three sample groups of carp cuts were investigated. One group of carp cuts was placed on top of flaked ice placed in polystyrene boxes. Two other groups were packaged in modified atmosphere with different gas ratios: 80%O2+20%CO2 (MAP 1) and 90%CO2+10%N2 (MAP 2). All carp cuts were stored in the same conditions at 3±0.5°C, and on 1, 3, 5, 7, 9, 11, 13, 15. and 17 days of storage, chemical testing was performed. The results obtained indicate that the packaging of common carp under 90%CO2+10%N2 slowed proteolytic reaction as well as secondary lipid oxidation.

Formation of biogenic amines and growth of spoilage-related microorganisms in pork stored under different packaging conditions applying PCA.

PubMed

Li, Miaoyun; Tian, Lu; Zhao, Gaiming; Zhang, Qiuhui; Gao, Xiaoping; Huang, Xianqing; Sun, Lingxia

2014-02-01

The objective of this study was to investigate the evolution of biogenic amines and spoilage-related microorganisms of chilled pork stored at 5 °C under various atmospheric conditions. The experimental packaging systems were pallet packaging, vacuum packaging (VP) and modified atmosphere packaging methods (MAP, 40%O2+40%CO2+20%N2), respectively. The results showed that about 74.26% of the variability could be explained by two first principal components analyzed by PCA in the pallet packaging, while in the vacuum and modified atmosphere packagings were about 85.21% and 79.14%, respectively. PC1 differentiated the indicators from packaging conditions. All the five microbial indicators and partial biogenic amines, gathering together, had high values at the positive side of PC1. Putrescine and cadaverine could reflect the spoilage evolution of fresh pork except for those in the pallet. Therefore, putrescine and cadaverine could be used as the spoilage indicators of chilled pork, of which the contents might reflect the spoilage degree. © 2013.

Modified Atmosphere Packaging and Its Feasibility for Military Feeding Systems

DTIC Science & Technology

1994-12-01

must be taken in all food processing . There are special precautions for NAP foods because a MAP food will not be sterilized and contamination or...Food Engineering. October: 62-63. 3 Rice, J., 1989. Modified Atmosphere Packaging. Food Processing . March: 60-76. 4 Coulon, M., and P. Louis, 1989...Prepared Foods. May:131. 9 Rice, J., 1989. Gas-Emitting Wafers: A Cost Effective NAP Approach. Food Processing . September:42. 10 Rice, J., 1991

The effect of modified atmospheres and packaging on patulin production in apples.

PubMed

Moodley, R S; Govinden, R; Odhav, B

2002-05-01

This study was undertaken to determine the effectiveness of modified atmospheres and packaging materials on the growth of Penicillium expansum and patulin production in apples. Granny Smith apples were surface sterilized with 76% ethanol and inoculated with 0.1 ml of a 1.1 x 10(7) spore/ml P. expansum spore suspension. The apples were packaged either in polyethylene (PE) or polypropylene (PP) and treated with three different gas combinations, viz., 58% CO2/42% N2, 48% CO2/52% N2, and 88% CO2/12% N2, and were then incubated for 14 days at 25 degrees C. Fungal growth was monitored every 2 to 4 days by measuring radial growth from the point of inoculation. After the 14th day, apples were pulped, and patulin was extracted, purified, and quantified by high-performance liquid chromatography. PP did not inhibit fungal growth in any of the atmospheres tested, and it only inhibited patulin production in atmospheric gas and 58% CO2/42% N2. PE was very effective and inhibited fungal growth by four- or fivefold, depending on the modified atmosphere. Patulin production in PE-packaged apples was almost completely inhibited by all three gas combinations. Gas chromatographic analysis of the PE-packaged samples before and after the incubation period showed that CO2 levels dropped and N2 levels increased for all of the atmospheres tested. Our studies showed conclusively that PE is an excellent packaging material for the storage of apples since it inhibited the growth of P. expansum, thereby allowing <3.2 microg/ml of patulin to be produced, regardless of gaseous environment.

Modified atmosphere packaging of fruits and vegetables.

PubMed

Kader, A A; Zagory, D; Kerbel, E L

1989-01-01

Modified atmospheres (MA), i.e., elevated concentrations of carbon dioxide and reduced levels of oxygen and ethylene, can be useful supplements to provide optimum temperature and relative humidity in maintaining the quality of fresh fruits and vegetables after harvest. MA benefits include reduced respiration, ethylene production, and sensitivity to ethylene; retarded softening and compositional changes; alleviation of certain physiological disorders; and reduced decay. Subjecting fresh produce to too low an oxygen concentration and/or to too high a carbon dioxide level can result in MA stress, which is manifested by accelerated deterioration. Packaging fresh produce in polymeric films can result in a commodity-generated MA. Atmosphere modification within such packages depends on film permeability, commodity respiration rate and gas diffusion characteristics, and initial free volume and atmospheric composition within the package. Temperature, relative humidity, and air movement around the package can influence the permeability of the film. Temperature also affects the metabolic activity of the commodity and consequently the rate of attaining the desired MA. All these factors must be considered in developing a mathematical model for selecting the most suitable film for each commodity.

Influence of modified atmosphere packaging on volatile compounds and physicochemical and antioxidant attributes of fresh-cut pineapple (Ananas comosus).

PubMed

Montero-Calderón, Marta; Rojas-Graü, María Alejandra; Aguiló-Aguayo, Ingrid; Soliva-Fortuny, Robert; Martín-Belloso, Olga

2010-04-28

The effects of modified atmosphere packaging on volatile compound content and physicochemical and antioxidant attributes of Gold cultivar fresh-cut pineapples were assessed throughout storage at 5 degrees C. Fresh-cut pineapple pieces were packed under LO (low oxygen, 12% O(2), 1% CO(2)), AIR (20.9% O(2)) and HO (high oxygen, 38% O(2)) headspace atmospheres. Methyl butanoate, methyl 2-methylbutanoate, and methyl hexanoate were the most abundant volatiles regardless of the packaging atmosphere and days of storage; whereas most odor active volatiles were methyl and ethyl 2-methylbutanoate, 2,5-dimethyl-4-methoxy-3(2H)-furanone and ethyl hexanoate. Physicochemical attributes of pineapple did not significantly vary, whereas vitamin C content and total antioxidant capacity were lower for fresh-cut pineapple in HO (488 +/- 38 mg/100 mg(fw) and 54.4 +/- 5.7%, respectively) than for LO and AIR packages. Storage life of fresh-cut pineapple was limited to 14 days by volatile compounds losses and fermentation processes.

Combined effects of gamma-irradiation and modified atmosphere packaging on quality of some spices.

PubMed

Kirkin, Celale; Mitrevski, Blagoj; Gunes, Gurbuz; Marriott, Philip J

2014-07-01

Thyme (Thymus vidgaris L.), rosemary (Rosmarinus officinalis L.), black pepper (Piper nigrum L.) and cumin (Cuminum cyminum L.) in ground form were packaged in either air or 100% N2 and γ-irradiated at 3 different irradiation levels (7kGy, 12kGy, 17kGy). Total viable bacterial count, yeast and mould count, colour, essential oil yield and essential oil composition were determined. Microbial load was not detectable after 12kGy irradiation of all samples. Irradiation resulted in significant changes in colour values of rosemary and black pepper. The discolouration of the irradiated black pepper was lower in modified atmosphere packaging (MAP) compared to air packaging. Essential oil yield of irradiated black pepper and cumin was lower in air packaging compared to MAP. Gamma-irradiation generally decreased monoterpenes and increased oxygenated compounds, but the effect was lower in MAP. Overall, spices should be irradiated under an O2-free atmosphere to minimise quality deterioration. Copyright © 2014 Elsevier Ltd. All rights reserved.

The effect of pre-treatment and modified atmosphere packaging on contents of phenolic compounds and sensory and microbiological quality of shredded celeriac.

PubMed

Radziejewska-Kubzdela, Elżbieta; Czapski, Janusz; Czaczyk, Katarzyna; Biegańska-Marecik, Róża

2014-04-01

The aim of this study was to determine the effect of washing (4 °C, 120 s) or soaking (4 °C, 600 s) of shredded celeriac in tap water on changes in contents of phenolic compounds, including furanocoumarins, and sensory and microbiological quality during 12 days of storage. The product was packaged in air or modified atmosphere containing 2/10/88 kPa O2/CO2/N2. The applied pre-treatment consisting of washing or soaking of shredded celeriac in water resulted in decreases in 8-methoxypsoralen content by approximately 50 and 70% respectively and phenolic content by 30% compared with samples that were not subjected to pre-treatment. During storage of shredded celeriac, a further significant (P ≤ 0.05) reduction in phenolic compounds and an approximately 2.5-fold increase in the total content of furanocoumarins were found. The application of modified atmosphere packaging had a significant effect on the maintenance of good sensory and microbiological quality of the tested product. Modified atmosphere packaging of shredded celeriac not subjected to pre-treatment made it possible to obtain a product with good sensory and microbiological quality and the highest content of phenolic compounds. The level of furanocoumarins recorded in the tested product does not constitute a health hazard. © 2013 Society of Chemical Industry.

Influence of modified atmosphere packaging on the shelf life of prebaked pizza dough with and without preservative added.

PubMed

Rodríguez, Valle; Medina, Luis; Jordano, Rafael

2003-04-01

The possible effect of different modified atmospheres on the shelf life of prebaked pizza dough, with and without added calcium propionate, was investigated. Three packaging atmospheres were tested: 20% CO2: 80% N2, 50% CO2: 50% N2, 100% CO2, and air (control). Samples were examined daily for visible mold growth and analysed after 2, 8, 17 and 31 days throughout storage (15-20 degrees C and 54-65% relative humidity, RH) for changes in gaseous composition, pH and microbial populations (mesophilic aerobic and anaerobic bacteria, lactic acid bacteria (LAB), and yeasts and molds). Microbiological results showed that molds had a greater sensitivity to CO2 than bacteria and yeasts. Products containing calcium propionate did not show mold growth throughout storage (31 days) when packaged in air or in CO2-enriched atmospheres (20, 50 and 100%). However, in pizza dough without preservative (calcium propionate), mold growth was evident after 7 days, except under 100% CO2 atmosphere (13 days) regardless of the packaging atmosphere. From these results we conclude that the addition of calcium propionate had more and decisive influence on the shelf life extension of prebaked pizza dough.

Quality changes of fresh filled pasta during storage: influence of modified atmosphere packaging on microbial growth and sensory properties.

PubMed

Sanguinetti, A M; Del Caro, A; Mangia, N P; Secchi, N; Catzeddu, P; Piga, A

2011-02-01

This study evaluated the shelf life of fresh pasta filled with cheese subjected to modified atmosphere packaging (MAP) or air packaging (AP). After a pasteurization treatment, fresh pasta was packaged under a 50/50 N(2)/CO(2) ratio or in air (air batch). Changes in microbial growth, in-package gas composition, chemical-physical parameters and sensory attributes were monitored for 42 days at 4 (°)C. The pasteurization treatment resulted in suitable microbiological reduction. MAP allowed a mold-free shelf life of the fresh filled pasta of 42 days, whereas air-packaged samples got spoilt between 7 and 14 days. The hurdle approach used (MAP and low storage temperature) prevented the growth of pathogens and alterative microorganisms. MAP samples maintained a high microbiological standard throughout the storage period. The panel judged MAP fresh pasta above the acceptability threshold throughout the shelf life.

Quality attributes of farmed eel (Anguilla anguilla) stored under air, vacuum and modified atmosphere packaging at 0 degrees C.

PubMed

Arkoudelos, John; Stamatis, Nikolaos; Samaras, Fotis

2007-01-01

The shelf life of fresh eel in various packaging conditions of atmospheric air, vacuum and modified atmosphere packaging (MAP) (40% CO(2), 30% N(2) and 30% O(2)) at 0 degrees C was investigated. All raw eel samples received acceptable sensory scores during the first 11+/-1 days of storage in atmospheric air, 11+/-1 days of storage in vacuum and finally 18+/-1 days of storage in MAP conditions. Using the microbial quality indicators the shelf life of eel packed in air, vacuum and MAP was estimated to be more than 18, 28 and 34 days, respectively. The main spoilage microorganisms under MAP conditions were lactic acid producing bacteria followed by Shewanella spp., pseudomonads, Enterobacteriaceae and yeasts. Chemical data revealed that pH, ammonia, glucose and lactate examinations might not be useful for monitoring eel quality differences.

Refrigerated poultry breast fillets packed in modified atmosphere and irradiated: bacteriological evaluation, shelf life and sensory acceptance

PubMed Central

Mantilla, Samira Pirola Santos; Santos, Érica Barbosa; de Freitas, Mônica Queiroz; de Carvalho Vital, Helio; Mano, Sérgio Borges; Franc, Robson Maia

2012-01-01

In the present study the effects on shelf life and sensory acceptance of gamma-irradiated refrigerated poultry breast fillets subjected to modified atmosphere packaging (80% CO2/20% N2 or vacuum) were investigated. After irradiation with 2 kGy, sensory acceptance tests and monitoring of bacterial growth were performed in order to determine the sanitary quality of the samples. It has been found that irradiation, used in combination with modified atmosphere packaging, can double the shelf life of refrigerated poultry breast fillets by reducing the populations of aerobic mesophilic and psychrotrophic bacteria, enterobacteria, coliforms, Listeria spp. and Aeromonas spp., without significantly modifying its color or its overall appearance, the lactic acid bacteria being the most resistant to exposure to radiation and carbon dioxide. PMID:24031967

Laser spectroscopy for totally non-intrusive detection of oxygen in modified atmosphere food packages

NASA Astrophysics Data System (ADS)

Cocola, L.; Fedel, M.; Poletto, L.; Tondello, G.

2015-04-01

A device for measuring the oxygen concentration inside packages in modified atmosphere working in a completely non-intrusive way has been developed and tested. The device uses tunable diode laser spectroscopy in a geometry similar to a short distance LIDAR: A laser beam is sent through the top film of a food package, and the absorption is measured by detecting the light scattered by the bottom of the container or by a portion of the food herein contained. The device can operate completely in a contactless way from the package, and the distances of absorption both outside and inside the package are measured with a triangulation system. The performances of the device have been tested for various types of containers, and absolute values for the oxygen concentration have been compared with standard albeit destructive measurements.

Overall quality and shelf life of minimally processed and modified atmosphere packaged 'ready-to-eat' pomegranate arils.

PubMed

Ayhan, Zehra; Eştürk, Okan

2009-06-01

Minimally processed ready-to-eat pomegranate arils have become popular due to their convenience, high value, unique sensory characteristics, and health benefits. The objective of this study was to monitor quality parameters and to extend the shelf life of ready-to-eat pomegranate arils packaged with modified atmospheres. Minimally processed pomegranate arils were packed in PP trays sealed with BOPP film under 4 atmospheres including low and super atmospheric oxygen. Packaged arils were stored at 5 degrees C for 18 d and monitored for internal atmosphere and quality attributes. Atmosphere equilibrium was reached for all MAP applications except for high oxygen. As a general trend, slight or no significant change was detected in chemical and physical attributes of pomegranate arils during cold storage. The aerobic mesophilic bacteria were in the range of 2.30 to 4.51 log CFU/g at the end of the storage, which did not affect the sensory quality. Overall, the pomegranate arils packed with air, nitrogen, and enriched oxygen kept quality attributes and were acceptable to sensory panelists on day 18; however, marketability period was limited to 15 d for the low oxygen atmosphere. PP trays sealed with BOPP film combined with either passive or active modified atmospheres and storage at 5 degrees C provided commercially acceptable arils for 18 d with high quality and convenience.

Maintaining quality of fresh-cut mangoes using antibrowning agents and modified atmosphere packaging.

PubMed

González-Aguilar, G A; Wang, C Y; Buta, J G

2000-09-01

Treatments to inhibit browning and decay and prolong shelf life of fresh-cut mangoes were investigated. Combinations of antibrowning agents and modified atmosphere packaging (MAP) resulted in a reduction of browning and deterioration of fresh-cut mangoes stored at 10 degrees C. Combinations of several browning inhibitors were more effective than those applied individually. Among these treatments, solutions containing 4-hexylresorcinol (0.001 M) (HR) plus potassium sorbate (0.05 M) (KS) and HR plus KS plus D-isoascorbic acid (0.5 M) (ER) reduced changes in color (L, a, and b) and microbial growth and did not affect sensory characteristics of fresh-cut mangoes. In general, these treatments did not affect significantly the changes in organic acids and sugar content of slices during the 14 days of storage at 10 degrees C. High humidity created in the in-package atmosphere alleviated tissue dryness and was an important factor in the ability of the antibrowning solutions to prevent browning and decay. It appears that the maintenance of quality of fresh-cut mangoes is more related to particular combinations of the antibrowning agents used rather than the modified atmosphere created inside the package. HR + ER + KS treatment in combination with MAP could be used to inhibit browning, decay, and deterioration of fresh-cut mangoes.

Effect of modified atmosphere and vacuum packaging on TVB-N production of rainbow trout (Oncorhynchus mykiss) and carp (Cyprinus carpio) cuts

NASA Astrophysics Data System (ADS)

Babić Milijašević, J.; Milijašević, M.; Đinović-Stojanović, J.; Vranić, D.

2017-09-01

The aim of our research was to examine the influence of packaging in modified atmosphere and vacuum on the total volatile basic nitrogen (TVB-N) content in muscle of rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio), as well as to determine the most suitable gas mixtures for packing of these freshwater species. Three sample groups of trout and carp cuts were investigated. The two groups were packaged in modified atmosphere with different gas ratios: 90%CO2+10%N2 (MAP 1) and 60%CO2+40%N2 (MAP 2), whereas the third group of fish cuts were vacuum packaged. During trials, the trout and carp cuts were stored in refrigerator at 3°C±0.5°C. Determination of TVB-N was performed on 1, 4, 7, 9, 12 and 14 days of storage. The obtained results indicate that the investigated mixtures of gases and vacuum had a significant influence on the values of TVB-N in trout and carp cuts. The lowest increase in TVB-N was established in trout and carp cuts packaged in MAP 1, whereas the highest increase was established in vacuum packaged cuts. Based on the obtained results, it can be concluded that the gas mixture consisting of 90% CO2 and 10% N2 was the most suitable for packaging of fresh trout and carp cuts in terms of TVB-N value.

Shelf-life extension of refrigerated Mediterranean mullet (Mullus surmuletus) using modified atmosphere packaging.

PubMed

Pournis, Nikolaos; Papavergou, Aikaterini; Badeka, Anastasia; Kontominas, Michael G; Savvaidis, Ioannis N

2005-10-01

The present work evaluated the quality and freshness characteristics and the effect of modified atmosphere packaging (MAP) on the shelf-life extension of refrigerated Mediterranean mullet using microbiological, biochemical, and sensory analyses. Fresh open sea red mullet (Mullus surmuletus) were packaged in four different atmospheres: M1, 10%/20%/70% (O2/ CO2/N2); M2, 10%/40%/50% (O2/CO2/N2); M3, 10%/60%/30% (O2/CO2/N2); identical fish samples were packaged in air. All fish were kept under refrigeration (4 +/- 0.5 degrees C) for 14 days. Of the three gas atmospheres, the 10%/40%/50% (M2) and 10%/ 60%/30% (M3) gas mixtures were the most effective for inhibiting growth of aerobic microflora in mullet samples until day 10 of refrigerated storage. H2S-producing bacteria and pseudomonads were part of the mullet microflora and their growth was partly inhibited under MAP conditions. Between these two bacterial groups, H2S-producing bacteria (including Shewanella putrefaciens) were dominant toward the end of the storage period, regardless of the packaging conditions. Brochothrix thermosphacta and lactic acid bacteria were found to be members of the final microbial flora of MAP and air-packaged mullet, whereas the Enterobacteriaceae population was lower than other bacterial groups. Of the chemical freshness indices determined, thiobarbituric acid values were variable in mullet samples irrespective of packaging conditions indicative of no specific oxidative rancidity trend. Based on sensorial data and aerobic plate count, trimethylamine nitrogen and total volatile basic nitrogen limit values in the range of ca. 15 to 23 and 52 to 60 mg N/100 g of fish muscle were obtained, respectively, for mullet packaged under modified atmosphere and air. Sensory analyses (odor and taste attributes) showed that the limit of sensorial acceptability was reached after ca. 6 days for the samples packaged in air, 8 days for the M1 and M3 samples, and after 10 days for the M2 samples. Respective shelf-life extension for fresh whole mullet was ca. 2 days (M1 and M3 gas mixtures), and 4 days (M2 gas mixture).

Total quality index of Agaricus bisporus mushrooms packed in modified atmosphere.

PubMed

Djekic, Ilija; Vunduk, Jovana; Tomašević, Igor; Kozarski, Maja; Petrovic, Predrag; Niksic, Miomir; Pudja, Predrag; Klaus, Anita

2017-07-01

The aim of this study was to develop a total quality index and examine the effects of modified atmosphere packaging (MAP) on the quality of Agaricus bisporus mushrooms stored for 22 days at 4 °C. Mushrooms were packaged under three MAPs: high nitrogen packaging (HNP), low carbon dioxide packaging (LCP) and low oxygen packaging (LOP). Passive MAP with air inside initially was used as the atmosphere treatment (AIR). This research revealed two phases in quality deterioration of A. bisporus mushrooms. During the first week, most of the quality parameters were not statistically different. Thereafter, odor intensities were stronger for all four types of packaging. Color difference and browning index values showed significantly lower color changes for AIR and LOP compared with HNP and LCP mushrooms. The best total quality index was calculated for LOP, followed by LCP and AIR. The findings of this study are useful with respect to examining two-component MAPs, separating the limiting factors (O 2 and CO 2 ) and evaluating quality deterioration effects and the total quality index of A. bisporus mushrooms. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Use of activated carbon inside modified atmosphere packages to maintain tomato fruit quality during cold storage.

PubMed

Bailén, Gloria; Guillén, Fabián; Castillo, Salvador; Serrano, María; Valero, Daniel; Martínez-Romero, Domingo

2006-03-22

Ethylene triggers the ripening process of tomato affecting the storage durability and shelf life (loss of quality) and inducing fruit decay. In this paper, an active packaging has been developed on the basis of the combination of modified atmosphere packaging (MAP) and the addition of granular-activated carbon (GAC) alone or impregnated with palladium as a catalyst (GAC-Pd). A steady-state atmosphere was 4 and 10 kPa for O2 and CO2 in control packages, while it was 8 and 7 kPa for O2 and CO2 in treated ones. The addition of GAC-Pd led to the lower ethylene accumulation inside packages, while the higher was obtained in controls. The parameters related to ripening showed that treated tomatoes exhibited a reduction in color evolution, softening, and weight loss, especially for GAC-Pd treatment. Moreover, these treatments were also effective in delaying tomato decay. After sensorial panel, tomatoes treated with GAC-Pd received the higher scores in terms of sweetness, firmness, juiciness, color, odor, and flavor. Results from the GC-MS analysis of the MAP headspace showed that 23 volatile compounds were identified in control packages, with these volatiles being significantly reduced in MAP-treated packages, which was correlated to the odor intensity detected by panelists after bag opening.

Type of packaging affects the colour stability of vitamin E enriched beef.

PubMed

Nassu, Renata T; Uttaro, Bethany; Aalhus, Jennifer L; Zawadski, Sophie; Juárez, Manuel; Dugan, Michael E R

2012-12-01

Colour stability is a very important parameter for meat retail display, as appearance of the product is the deciding factor for consumers at time of purchase. This study investigated the possibility of extending appearance shelf-life through the combined use of packaging method (overwrapping - OVER, modified atmosphere - MAP, vacuum skin packaging - VSP and a combination of modified atmosphere and vacuum skin packaging - MAPVSP) and antioxidants (vitamin E enriched beef). Retail attributes (appearance, lean colour, % surface discolouration), as well as colour space analysis of images for red, green and blue parameters were measured over 18days. MAPVSP provided the most desirable retail appearance during the first 4days of retail display, while VSP-HB had the best colour stability. Overall, packaging type was more influential than α-tocopherol levels on meat colour stability, although α-tocopherol levels (>4μgg(-1) meat) had a protective effect when using high oxygen packaging methods. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

A chemometrics approach applied to Fourier transform infrared spectroscopy (FTIR) for monitoring the spoilage of fresh salmon (Salmo salar) stored under modified atmospheres.

PubMed

Saraiva, C; Vasconcelos, H; de Almeida, José M M M

2017-01-16

The aim of this work was to investigate the potential of Fourier transform infrared spectroscopy (FTIR) to detect and predict the bacterial load of salmon fillets (Salmo salar) stored at 3, 8 and 30°C under three packaging conditions: air packaging (AP) and two modified atmospheres constituted by a mixture of 50%N 2 /40%CO 2 /10%O 2 with lemon juice (MAPL) and without lemon juice (MAP). Fresh salmon samples were periodically examined for total viable counts (TVC), specific spoilage organisms (SSO) counts, pH, FTIR and sensory assessment of freshness. Principal components analysis (PCA) allowed identification of the wavenumbers potentially correlated with the spoilage process. Linear discriminant analysis (LDA) of infrared spectral data was performed to support sensory data and to accurately identify samples freshness. The effect of the packaging atmospheres was assessed by microbial enumeration and LDA was used to determine sample packaging from the measured infrared spectra. It was verified that modified atmospheres can decrease significantly the bacterial load of fresh salmon. Lemon juice combined with MAP showed a more pronounced delay in the growth of Brochothrix thermosphacta, Photobacterium phosphoreum, psychrotrophs and H 2 S producers. Partial least squares regression (PLS-R) allowed estimates of TVC and psychrotrophs, lactic acid bacteria, molds and yeasts, Brochothrix thermosphacta, Enterobacteriaceae, Pseudomonas spp. and H 2 S producer counts from the infrared spectral data. For TVC, the root mean square error of prediction (RMSEP) value was 0.78logcfug -1 for an external set of samples. According to the results, FTIR can be used as a reliable, accurate and fast method for real time freshness evaluation of salmon fillets stored under different temperatures and packaging atmospheres. Copyright © 2016 Elsevier B.V. All rights reserved.

Improving the lean muscle color of dark-cutting beef by aging, antioxidant-enhancement, and modified atmospheric packaging.

PubMed

Wills, K M; Mitacek, R M; Mafi, G G; VanOverbeke, D L; Jaroni, D; Jadeja, R; Ramanathan, R

2017-12-01

The objective was to evaluate the effects of wet-aging, rosemary-enhancement, and modified atmospheric packaging on the color of dark-cutting beef during simulated retail display. No-roll dark-cutting strip loins ( = 12; pH > 6.0) were selected from a commercial packing plant within 3 d postharvest. Using a balanced incomplete block design, dark-cutting loins were sectioned in half, and assigned to 1 of 3 aging periods: 7, 14, or 21 d. After respective aging, each aged section was divided into 3 equal parts, and randomly assigned to 1 of 3 enhancement treatments: nonenhanced dark-cutting, dark-cutter enhanced with 0.1% rosemary, and dark-cutter enhanced with 0.2% rosemary. Following enhancement, steaks were randomly assigned to 1 of 3 packaging treatments: high-oxygen modified atmospheric packaging (HiOx-MAP; 80% O and 20% CO), carbon monoxide modified atmospheric packaging (CO-MAP; 0.4% CO, 69.6% N, and 30% CO), and polyvinyl chloride overwrap (PVC; 20% O). Instrumental and visual color measurements were recorded during 5 d simulated retail display. Lipid oxidation was determined utilizing the thiobarbituric acid reactive substances (TBARS) method. There was a significant packaging × enhancement × display time interaction for values and chroma ( 0.001). On d 0 of display, dark-cutting steaks enhanced with 0.1% and 0.2% rosemary and packaged in HiOx-MAP had greater ( 0.001) values and chroma than other dark-cutting packaging/enhancement treatments. A significant packaging × enhancement × display time interaction resulted for values ( 0.001). Dark-cutting steaks enhanced with 0.2% rosemary and packaged in HiOx-MAP was lighter ( 0.001; greater values) than other dark-cutting treatments on d 5 of display. There were no differences ( 0.34) in discoloration scores on d 5 among different dark-cutting treatments when steaks were packaged in HiOx- and CO-MAP. There was an aging period × enhancement × packaging interaction ( < 0.0033) for lipid oxidation. On d 0 of display, there were no differences ( 0.54) in TBARS values between different aging periods and enhancement treatments. Dark-cutting steaks enhanced with 0.2% rosemary had lower ( 0.001) TBARS values than 0.1% rosemary on d 5 when aged for 21 d and in HiOx-MAP. The results suggest that rosemary enhancement with CO- or HiOx-MAP has the potential to improve the surface color of dark-cutting beef.

Characterization by culture-dependent and culture-independent methods of the bacterial population of suckling-lamb packaged in different atmospheres.

PubMed

Osés, Sandra M; Diez, Ana M; Melero, Beatriz; Luning, Pieternel A; Jaime, Isabel; Rovira, Jordi

2013-12-01

This study offers insight into the dynamics of bacterial populations in fresh cuts of suckling lamb under four different atmospheric conditions: air (A), and three Modified Atmosphere Packaging (MAP) environments, 15%O2/30%CO2/55%N2 (C, commercial), 70%O2/30%CO2 (O), and 15%O2/85%CO2 (H) for 18 days. Microbial analyses by both conventional methods and PCR-DGGE were performed. Controversial and surprising results emerged from comparing both methods in relation to the genus Pseudomonas. Thus, conventional methods detected the presence of high numbers of Pseudomonas colonies, although PCR-DGGE only detected this genus in air-packaged samples. PCR-DGGE detected higher microbial diversity in the control samples (A) than in the modified atmospheres (C, O, H), having atmosphere H the fewest number of species. Brochothrix thermosphacta, LAB (Carnobacterium divergens and Lactobacillus sakei), and Escherichia spp. were detected in all the atmospheres throughout storage. Moreover, previously undescribed bacteria from lamb meat such as Enterobacter hormaechei, Staphylococcus equorum and Jeotgalicoccus spp. were also isolated in this study by DGGE. Additionally, qPCR analysis was used to detect and characterize strains of Escherichia coli. Virulence genes (stx1, stx2 and eae) were detected throughout storage in 97% of the samples. A high CO2 atmosphere was the most effective packaging combination doubling storage time in comparison with commercial atmosphere. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of lactate and modified atmospheric packaging on premature browning in cooked ground beef patties.

PubMed

Mancini, R A; Ramanathan, R; Suman, S P; Konda, M K R; Joseph, P; Dady, G A; Naveena, B M; López-López, I

2010-06-01

Our objectives were to determine the effects of lactate and modified atmosphere packaging on raw surface color, lipid oxidation, and internal cooked color of ground beef patties. Eight chubs (85% lean) were divided in half and each half was either assigned to the control (no lactate) or mixed with 2.5% lactate (w/w). Following treatment, patties were prepared and packaged in either vacuum, PVC (atmospheric oxygen level), high-oxygen (80% O(2)+20% CO(2)), or 0.4% CO (30% CO(2)+69.6% N(2)) and stored for 0, 2, or 4days at 2 degrees C. After storage, raw surface color and lipid oxidation were measured and patties were cooked to either 66 degrees C or 71 degrees C. Lactate improved (p<0.05) color stability of PVC, high-oxygen, and vacuum packaged raw patties, but had no effect (p>0.05) on the a * values and visual color scores of patties in 0.4% CO. Lactate decreased (p<0.05) lipid oxidation in all packaging atmospheres. Nevertheless, high-oxygen and PVC-packaged patties had more (p<0.05) lipid oxidation than patties in CO and vacuum. Lactate had no effect (p>0.05) on premature browning, whereas patties packaged in high-oxygen demonstrated premature browning. Conversely, cooked patties in 0.4% CO and vacuum were more red (p<0.05) than both high-oxygen and PVC-packaged patties. Although lactate improved raw color stability, it did not minimize premature browning in cooked ground beef patties. Copyright 2010 Elsevier Ltd. All rights reserved.

Effect of modified atmospheric packaging on the shelf life of Kalakand and its influence on microbial, textural, sensory and physico-chemical properties.

PubMed

Jain, Vishal; Rasane, Prasad; Jha, Alok; Sharma, Nitya; Gautam, Anuj

2015-07-01

Kalakand, a popular traditional milk sweet of Indian sub-continent, was packaged under air and modified atmospheric packaging (MAP) conditions (98 % N2, 98 % CO2 and 50 % N2: 50 % CO2). The samples were stored at 10, 25 and 37 °C and evaluated for various physico-chemical, microbial, textural and sensory changes, in order to establish the applicability of MAP for storage of Kalakand. It could be established that the MAP conditions of 50 % N2: 50 % CO2and storage at 10 °C, were the most suitable conditions for preserving the Kalakand for upto 60 days.

Shelf-Life Extension of Chill-Stored Beef Longissimus Steaks Packaged under Modified Atmospheres with 50% O2 and 40% CO2.

PubMed

Yang, Xiaoyin; Niu, Lebao; Zhu, Lixian; Liang, Rongrong; Zhang, Yimin; Luo, Xin

2016-07-01

This study was conducted to compare the shelf-life of beef steaks stored in different packaging conditions: overwrapped (OW) packaging and 2 modified atmosphere packaging systems (MAP): 80% O2 MAP (80% O2 /20% CO2 ) and 50% O2 MAP (50% O2 /40% CO2 /10% N2 ). Steaks were stored at 2 °C for 20 d. Headspace gas composition, microbial counts, color stability, pH, purge loss, and lipid oxidation were monitored. Among the packaging types, 50% O2 MAP was superior to OW packaging and 80% O2 MAP in delaying bacterial growth and extending shelf-life to 20 d. 50% O2 MAP also gave steaks an acceptable color during storage. No significant differences were observed in color stability of steaks packaged in both 50% O2 MAP and 80% O2 MAP. This study reveals 50% O2 MAP is a realistic alternative to preserve beef steaks efficiently. © 2016 Institute of Food Technologists®

Effects of vacuum and modified atmosphere on textural parameters and structural proteins of cultured meagre (Argyrosomus regius) fillets.

PubMed

Sáez, María I; Martínez, Tomás F; Cárdenas, Salvador; Suárez, María D

2015-09-01

The influence of two preservation strategies (vacuum package and modified atmosphere package) on the post-mortem changes of textural parameters, pH, water holding capacity, sarcoplasmic and myofibrillar proteins, and collagen content of meagre (Argyrosomus regius) fillets was studied. Fillets were stored in a cold room in aerobic (control, C), vacuum (V) and modified atmosphere (MA) package. Samples were withdrawn at six sampling points throughout 15-day storage, and post-mortem changes were assessed. The textural parameters were significantly enhanced in V and MA compared to C. Both V and MA treatments reduced the intensity of a group of myofibrillar protein fractions (140-195 kDa) and increased insoluble collagen compared to C. Consequently, the post-mortem flesh softening in C was attributed to increased proteolysis in both intracellular and extracellular structural proteins. The preservation of the textural and biochemical characteristics of meagre fillets subjected to V and MA treatments makes these two treatments highly recommendable for the commercialization of meagre fillets. © The Author(s) 2014.

Botulism challenge studies of a modified atmosphere package for fresh mussels: inoculated pack studies.

PubMed

Newell, C R; Ma, Li; Doyle, Michael

2012-06-01

A series of botulism challenge studies were performed to determine the possibility of production of botulinum toxin in mussels (Mytilus edulis) held under a commercial high-oxygen (60 to 65% O(2)), modified atmosphere packaging (MAP) condition. Spore mixtures of six strains of nonproteolytic Clostridium botulinum were introduced into mussel MAP packages receiving different packaging buffers with or without the addition of lactic acid bacteria. Dye studies and package flipping trials were conducted to ensure internalization of spores by packed mussels. Inoculated mussel packages were stored at normal (4°C) and abusive (12°C) temperatures for 21 and 13 days, respectively, which were beyond the packaged mussels' intended shelf life. Microbiological and chemical analyses were conducted at predetermined intervals (a total of five sampling times at each temperature), including total aerobic plate counts, C. botulinum counts, lactic acid bacterial counts, package headspace gas composition, pH of packaging buffer and mussel meat, and botulinum toxin assays of packaging buffer and mussel meat. Results revealed that C. botulinum inoculated in fresh mussels packed under MAP packaging did not produce toxin, even at an abusive storage temperature and when held beyond their shelf life. No evidence was found that packaging buffers or gas composition influenced the lack of botulinum toxin production in packed mussels.

Study of the effect of post-packaging pasteurization and argon modified atmosphere packaging on the sensory quality and growth of endogenous microflora of a sliced cooked meat product.

PubMed

Pérez-Rodríguez, Fernando; Zamorano, Arturo Rivera; Posada-Izquierdo, Guiomar Denisse; García-Gimeno, Rosa María

2014-01-01

The objective of this work was to study the effect of post-packaging pasteurization on the sensory quality and growth of natural microorganisms during refrigerated storage (6 °C) of a cooked meat product considering two packaging atmospheres based on mixture of typical gases (CO(2)/N(2) (22/78%) and novel gases (CO(2)/Ar (17/83%)). Growth of lactic acid bacteria was significantly different between samples with and without post-packaging pasteurization, showing a growth rate >0.44 and equal to 0.28 log cfu/day, respectively. For samples with post-packaging pasteurization, atmosphere CO(2)/Ar resulted in a lower growth of lactic acid bacteria and a better sensory quality. Overall, samples without post-packaging pasteurization did not show a significant reduction of sensory quality during storage time (121 days) while samples with post-packaging pasteurization showed deterioration in their sensory quality. Further investigation is needed to obtain more definitive conclusions about the effect of post-packaging pasteurization and argon-based packaging atmospheres on cooked meat products.

Extending the shelf life of edible flowers with controlled release of 1-methylcyclopropene and modified atmosphere packaging.

PubMed

Kou, Liping; Turner, Ellen R; Luo, Yaguang

2012-05-01

Edible flowers have great sensory appeal, but their extremely short shelf life limits their commercial usage. Postharvest 1-methylcyclopropene (1-MCP) treatment is used to counter ethylene activity and delay senescence in fresh produce; however, its potential application in edible flowers has not been tested. The objective of this study was to investigate the effect of 1-MCP treatment with modified atmosphere packaging (MAP) on the shelf life of edible flowers. Freshly harvested carnations and snapdragons were packaged in trays with or without 0.5 μL/L of 1-MCP, sealed with a gas permeable film, and stored at 5 °C. Package atmospheres, tissue electrolyte leakage, and flower quality were evaluated on days 0, 7, and 14. Treatment with 1-MCP resulted in significantly slower changes in package headspace O(2), CO(2), and C(2)H(4) partial pressures, maintained higher overall quality of both flower species and reduced electrolyte leakage and abscission in snapdragon. All samples prepared with MAP had significantly reduced dehydration and higher overall quality compared to flowers packaged commercially in plastic clamshell containers. Treatments with controlled release of 1-MCP and MAP significantly extended storage life of edible carnation and snapdragon flowers. © 2012 Institute of Food Technologists®

Effect of reduction of oxygen concentration in modified atmosphere packaging on bovine M. longissimus lumborum and M. gluteus medius quality traits.

PubMed

Łopacka, Joanna; Półtorak, Andrzej; Wierzbicka, Agnieszka

2017-02-01

This paper reports the impact of modified atmosphere gas compositions with different concentrations of CO 2 /O 2 /N 2 on physicochemical traits of beef steaks from M. longissimus lumborum and M. gluteus medius. Samples were stored at +2°C for 12days. The gas compositions were as follows: (i) 50% O 2 /20% CO 2 /30% N 2 (MAP1), (ii) 65% O 2 /20% CO 2 /15% N 2 (MAP2) and (iii) 80% O 2 /20% CO 2 (MAP3). Packaging atmosphere did not affect CIEL*a*b* colour coordinates, which were affected by storage time and by muscle type. Lipid oxidation in M. longissimus lumborum was affected by packaging treatment; however packaging treatment×storage time interaction affected lipid oxidation significantly. Results showed that reduction of oxygen from the commercially used 80% to 50% does not negatively impact colour properties and state of myoglobin, but significantly lowers oxidative deterioration of M. longissimus lumborum at the end of storage. Copyright © 2016. Published by Elsevier Ltd.

Combined effects of gamma irradiation and a modified atmospheric packaging on the physicochemical characteristics of sausage

NASA Astrophysics Data System (ADS)

Ahn, Hyun-Joo; Kim, Jae-Hyun; Jo, Cheorun; Lee, Ju-Woon; Yook, Hong-Sun; Kim, Hee-Yun; Byun, Myung-Woo

2004-09-01

This study is to investigate the combined effects of irradiation and a modified atmospheric packaging (MAP) on the color, nitrosoheme pigments (NO-Mb), residual nitrite and N-nitrosodimethylamine (NDMA) in sausage during storage. Sausage with air, vacuum, CO 2, N 2, or CO 2/N 2 packaging was irradiated at 5 kGy. Irradiation reduced the red color of sausage, and a vacuum or MAP was effective in minimizing the loss of redness. The reduction of NO-Mb was observed by irradiation, while the MAP was more effective in maintaining the NO-Mb than the aerobic ones. Residual nitrite was reduced by irradiation, and the contents were lower under vacuum or MAP than aerobic ones. NDMA was significantly reduced by irradiation.

Postharvest color and texture retention in organic Chinese red raspberry and sea-buckthorn fruit during modified atmosphere storage

USDA-ARS?s Scientific Manuscript database

Color and texture are among the key quality attributes for small fruit. Postharvest approaches such as modified atmosphere packaging (MAP) along with cold chain management have been shown to support retention of fruit quality during handling and distribution. The objective of this study was to inves...

Preservation of fresh meat with active and modified atmosphere packaging conditions.

PubMed

Skandamis, Panagiotis N; Nychas, George-John E

2002-11-15

The sensory, microbiological and physicochemical attributes of fresh meat stored at 5 and 15 degrees C were affected by the combined effect of volatile compounds of oregano essential oil and modified atmosphere packaging conditions (40% CO2/30% N2/30% O2, 100% CO2, 80% CO2/20% air, vacuum pack and air). It was found that the extension of shelf life of meat samples depended on the packaging conditions and augmented in the order: air < vacuum pack < 40% CO2/30% N2/30% O2 < 80% CO2/ 20% air < 100% CO2. Longer shelf life was observed in samples supplemented with the volatile compounds of oregano essential oil and stored under the same packaging conditions mentioned above. The extension of shelf life may be due to the synergistic effect of volatile compounds of oregano essential oil and the modified atmosphere packaging used on the microbiological and physicochemical characteristics of meat. Indeed, both these hurdles can prolong and delay microbial growth or suppress the final counts of the spoilage microorganisms in comparison with the 'control' samples. The effect of essential oil volatile compounds was even more pronounced on the physicochemical changes of meat samples caused by microbial association. Oregano essential oil delayed glucose and lactate consumption, both indicators of meat spoilage aerobically as well as under 40% CO2/30% N2/30% O2, and 100% CO2. Finally, changes in other metabolites such as formic acid were also observed.

Quality of Meat (Longissimus dorsi) from Male Fallow Deer (Dama dama) Packaged and Stored under Vacuum and Modified Atmosphere Conditions

PubMed Central

Piaskowska, N.; Daszkiewicz, T.; Kubiak, D.; Zapotoczny, P.

2016-01-01

This study evaluated the effect of vacuum and modified atmosphere (40% CO2+60% N2, MA) packaging on the chemical composition, physicochemical properties and sensory attributes of chill-stored meat from 10 fallow deer (Dama dama) bucks at 17 to 18 months of age. The animals were hunter-harvested in the forests of north-eastern Poland. During carcass dressing (48 to 54 h post mortem), both musculus longissimus muscles were cut out. Each muscle was divided into seven sections which were allocated to three groups: 0, A, and B. Samples 0 were immediately subjected to laboratory analyses. Samples A were vacuum-packaged, and samples B were packaged in MA. Packaged samples were stored for 7, 14, and 21 days at 2°C. The results of the present study showed that the evaluated packaging systems had no significant effect on the quality of fallow deer meat during chilled storage. However, vacuum-packaged meat samples were characterised by greater drip loss. Vacuum and MA packaging contributed to preserving the desired physicochemical properties and sensory attributes of meat during 21 days of storage. Regardless of the packaging method used, undesirable changes in the colour, water-holding capacity and juiciness of meat, accompanied by tenderness improvement, were observed during chilled storage. PMID:27165026

Headspace volume and percentage of carbon monoxide affects carboxymyoglobin layer development of modified atmosphere packaged beef steaks.

PubMed

Raines, Christopher R; Hunt, Melvin C

2010-01-01

Carboxymyoglobin (COMb) development of beef Longissimus lumborum as related to molecular CO availability and package headspace volume was evaluated. Steaks from six pairs of USDA Select strip loins were packaged in modified atmosphere packages with 0.2%, 0.4%, or 0.8% CO and 30% CO(2) and balanced with N(2) to obtain meat-to-gas ratios of 0.4, 0.7, and 1.1, and CO molar concentrations of 0.07, 0.10, and 0.20 mMol. Steak redness (CIE a*), COMb layer thickness, percentage of CO in the headspace, visual display color, and bloom intensity scores were evaluated 4 and 7 d after packaging. Greater concentration of CO in a smaller headspace resulted in a thicker COMb layer compared with lesser concentration of CO in a larger headspace, regardless of moles CO available. The combined effects of concentration of CO and headspace volume had a greater impact on COMb development than millimoles of CO in the package headspace. Package headspace can be reduced and the concentration of CO can be increased without detriment to fresh beef color or consumer safety.

Effect of high oxygen modified atmosphere packaging on microbial growth and sensorial qualities of fresh-cut produce.

PubMed

Jacxsens, L; Devlieghere, F; Van der Steen, C; Debevere, J

2001-12-30

The application of High Oxygen Atmospheres (HOA) (i.e. > 70% O2) for packaging ready-to-eat vegetables was evaluated as an alternative technique for low O2 Equilibrium Modified Atmosphere (EMA) packaging (3% O2-5% CO2-balance N2) for respiring products. Comparative experiments between both techniques were performed in-vitro and in-vivo. Typical spoilage causing microorganisms (Pseudomonas fluorescens, Candida lambica), the moulds Botrytis cinerea, Aspergillus flavus and the opportunistic psychrotrophic human pathogenic microorganism associated with refrigerated minimally processed vegetables. Aeromonas caviae (HG4), showed a retarded growth during the conducted in-vitro studies at 4 degrees C in 70%, 80% and 95% O2 as examples of HOA compared to the in-vitro experiments in 5% O2 (as example of EMA packaging) and the effect was more pronounced in 95% O2. The effect of the high O2-concentrations on the human pathogen Listeria monocytogenes resulted in an extended lag phase (95% O2). The plant pathogen Erwinia carotovora was increasingly stimulated by increasing high O2-concentrations. During a storage experiment of three types of ready-to-eat vegetables (mushroom slices, grated celeriac and shredded chicory endive), which are sensitive to enzymatic browning and microbial spoilage, the effect of EMA and HOA (95% O2-5% N2) on their quality and shelf life was compared. High O2 atmospheres were found to be particularly effective in inhibiting enzymatic browning of the tested vegetables. Also, the microbial quality was better as a reduction in yeast growth was observed. The HOA can be applied as an alternative for low O2 modified atmospheres for some specific types of ready-to-eat vegetables, sensitive to enzymatic browning and spoilage by yeasts.

Shelf life extension of whole Norway lobster Nephrops norvegicus using modified atmosphere packaging.

PubMed

Gornik, Sebastian G; Albalat, Amaya; Theethakaew, Chonchanok; Neil, Douglas M

2013-11-01

Once a nuisance by-catch, today the Norway lobster (Nephrops norvegicus) is a valuable UK fisheries commodity. Unfortunately, the species is very susceptible to quality deterioration post harvest as it quickly develops black spots and also spoils rapidly due to bacterial growth. Treatment with chemicals can stop the blackening and carefully monitored cold storage can result in a sensory shelf life of up to 6.5 days. The high susceptibility to spoilage greatly restricts the extent to which N. norvegicus can be distributed to retailers and displayed for sale. The application of modified atmosphere (MA) could be extremely beneficial, allowing the chilled product to stay fresh for a long period of time, thus ensuring higher sales. In the present study, we identified a gas mix for the MA packaging (MAP) of whole N. norvegicus lobster into 200 g retail packs. Our results show that a shelf life extension to 13 days can be achieved when retail packs are stored in MAP at 1 °C. Effectiveness of the MAP was evaluated by using a newly developed QIM for MA-packaged whole N. norvegicus and also by analyzing bacterial plate counts. Changes in the microflora and effects of different storage temperatures on the quality of the MA packs are also presented. The main specific spoilage organism (SSO) of modified atmosphere packaged Norway lobster is Photobacterium phosphoreum. © 2013.

Shelf-life extension of cod fillets with an acetate buffer spray prior to packaging under modified atmospheres.

PubMed

Boskou, G; Debevere, J

2000-01-01

Fresh cod fillets (Gadus morhua) were sprayed with a 10% acetate buffer (pH 5.6), packed with an industrial gas-flushing packaging machine under modified atmospheres (50% CO2--45% O2--5% N2, 2 cm3/1 g gas/product ratio) and stored at 7 degrees C for 12 days. Control cod fillets were directly packed and stored under the same conditions. A reduction of the aerobic plate counts was observed immediately after the cod fillets had been sprayed. During storage under modified atmospheres, there was complete inhibition of H2S-producing bacteria and Enterobacteriaceae in the treated cod fillets. Production of total volatile bases and trimethylamine (TMA) was inhibited in treated fillets for 10 days' storage under modified atmospheres. Inhibition of TMA production can be attributed to growth inhibition of H2S-producing bacteria, inhibition of the trimethylamine oxide (TMAO)-dependent metabolism of TMAO-reducing bacteria and the stable pH during storage. The shelf-life, at 7 degrees C, of treated cod fillets, based on cooked flavour score, was almost 12 days, ca 8 days more than shelf-life of the control fillets.

Improvement of the overall quality of table grapes stored under modified atmosphere packaging in combination with natural antimicrobial compounds.

PubMed

Guillén, F; Zapata, P J; Martínez-Romero, D; Castillo, S; Serrano, M; Valero, D

2007-04-01

Consumers demand new means of preservation with absence of chemicals. In this work a package was developed (thermosealed baskets) with grapes wrapped with 2 distinct films (M and P) with different permeability (medium and high, respectively) without or with the addition of a mixture of eugenol, thymol, and carvacrol. Table grapes stored on air (control) lost their quality attributes very rapidly, manifested by accelerated weight loss, color changes, softening, and increase in soluble solids concentration and titratable acidity ratio (SSC/TA). The use of modified atmosphere packaging (MAP) alone retarded these changes, the effects being significantly greater when essential oils were added (especially for M film), although atmospheric composition was not affected by incorporating essential oils. In addition, microbial counts (molds and yeasts and mesophilic aerobics) were drastically decreased and accompanied by lower occurrence of berry decay. Although slight odor was detected after opening the packages, absence of the typical flavor of these compounds was found by trained panelists after tasting the berries. Thus, with this safe, simple, and innovative technology, the overall quality (sensory and safety) could be improved and considered as a toll alternative to the use of synthetic fungicides.

Effect of modified atmosphere packaging on the shelf life of rainbow trout (Oncorhynchus mykiss, Walbaum 1792) mince.

PubMed

Kocatepe, Demet; Turan, Hülya; Altan, Can Okan; Keskin, Irfan; Ceylan, Asuman

2016-06-01

This paper reports the effect of different concentrations of CO2/N2 gases on chemical/sensorial stability, color properties (L*, a*, and b* values), and microbiological properties of trout mince stored at 3 ± 1℃. The gas mixtures were used as follows; 60%CO2 + 40%N2 (B), 75%CO2 + 25%N2 (C), 40%CO2 + 60%N2 (D). Control samples (A) were packed under atmospheric air. Analyses were carried out on the 1st, 4th, 8th, 12th, 16th, 20th, 24th and 28th days of storage. Among three modified atmosphere gas compositions, the best preservation method and most suitable gas concentration for trout mince were found in group C including 75% CO2 The inconsumable day of trout mince packed with air (control) and MAPs (Modified Atmosphere Packaging) (group B, C, and D) were 12th, 16th, 24th, and 16th days, respectively. © The Author(s) 2015.

Recent Developments in Film and Gas Research in Modified Atmosphere Packaging of Fresh Foods.

PubMed

Zhang, Min; Meng, Xiangyong; Bhandari, Bhesh; Fang, Zhongxiang

2016-10-02

Due to the rise of consumer's awareness of fresh foods to health, in the past few years, the consumption of fresh and fresh-cut produces has increased sturdily. Modified atmosphere packaging (MAP) possesses a potential to become one of the most appropriate technologies for packaging fresh and fresh-cut produces. The MAP has advantages of extending the shelf-life, preserving or stabilizing the desired properties of fresh produces, and convenience in handing and distribution. The success of MAP-fresh foods depends on many factors including types of fresh foods, storage temperature and humidity, gas composition, and the characteristics of package materials. This paper reviews the recent developments highlighting the most critical factors of film and gas on the quality of MAP fresh foods. Although the innovations and development of food packaging technology will continue to promote the development of novel MAP, concentrated research and endeavors from scientists and engineers are still important to the development of MAP that focuses on consumers' requirements, enhancing product quality, environmental friendly design, and cost-effective application.

Postharvest changes in the phenolic profile of watercress induced by post-packaging irradiation and modified atmosphere packaging.

PubMed

Pinela, José; Barros, Lillian; Barreira, João C M; Carvalho, Ana Maria; Oliveira, M Beatriz P P; Santos-Buelga, Celestino; Ferreira, Isabel C F R

2018-07-15

The effects of γ-ray irradiation and modified atmosphere packaging (MAP) on watercress (Nasturtium officinale R. Br.) phenolic compounds were evaluated after 7-day storage at 4 °C. Irradiation doses of 1, 2 and 5 kGy were tested, as well as vacuum-packaging and MAP enriched with 100% N 2 and Ar. A non-irradiated, air-packaged control was included in all experiments. p-Coumaric acid was the most abundant compound in fresh watercress, followed by quercetin-3-O-sophoroside and isorhamnetin-O-hydroxyferuloylhexoside-O-hexoside. Four kaempferol glycoside derivatives were identified for the first time in this species. In general, flavonoids predominated over phenolic acids. Samples stored under vacuum and irradiated at 2 kGy revealed lower phenolic levels. Ar-enriched MAP and control conditions preserved the initial phenolic content. The 5 kGy dose also maintained concentrations of flavonoids and total phenolic compounds, but increased the phenolic acids content. Additionally, flavonoids were found strongly correlated to DPPH scavenging activity and β-carotene bleaching inhibition capacity. Copyright © 2018 Elsevier Ltd. All rights reserved.

Stability of lamb loin stored under refrigeration and packed in different modified atmosphere packaging systems.

PubMed

Fernandes, Rafaella de Paula Paseto; Freire, Maria Teresa de Alvarenga; de Paula, Elisa Silva Maluf; Kanashiro, Ana Livea Sayuri; Catunda, Fernanda Antunes Pinto; Rosa, Alessandra Fernandes; Balieiro, Júlio Cesar de Carvalho; Trindade, Marco Antonio

2014-01-01

The aim of the present study was to evaluate the effect of different modified atmosphere packaging (MAP) systems (vacuum, 75% O2+25% CO2 and 100% CO2) on the stability of lamb loins stored at 1±1°C for 28 days. Microbiological (counts of aerobic and anaerobic psychrotrophic microorganisms, coliform at 45°C, coagulase-positive staphylococci and lactic acid bacteria and presence of Salmonella), physical and chemical (thiobarbituric acid reactive substances [TBARS], objective color, pH, water loss from cooking [WLC] and shear force), sensory (acceptance testing using a 9-point hedonic scale) and gas composition analyses were performed. Lamb meat remained stable with respect to the majority of the evaluated physical and chemical indexes and within the standards established by Brazilian legislation for pathogenic microorganisms throughout the storage period in all three packaging systems. However, with respect to psychrotrophic microorganisms, 100% CO2 packaging system provided increased stability despite presenting lower appearance preference. © 2013.

Bacterial microbiota profile in gills of modified atmosphere-packaged oysters stored at 4 °C.

PubMed

Chen, Huibin; Wang, Meiying; Lin, Xiangzhi; Shi, Caihua; Liu, Zhiyu

2017-02-01

As filter-feeding bivalves, oysters can accumulate microorganisms into their gills, causing spoilage and potential safety issues. This study aims to investigate the changes in the gill microbiota of oysters packed under air and modified atmospheres (MAs, 50% CO 2 : 50% N 2 , 70% CO 2 : 30% O 2 , and 50% CO 2 : 50% O 2 ) during storage at 4 °C. The diversity of bacterial microbiota in oyster gills was profiled through polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis on the 16S rRNA gene V3 region to describe the variation during the entire storage period. The DGGE profile revealed high bacterial diversity in the air- and MA-packaged oyster gills, and the spoilage bacterial microbiota varied in the MA-packaged oyster gills. Results indicated that CO 2 :O 2 (70%:30%) was suitable for oyster MA packaging and that high bacterial loads in oyster gills need to be considered during storage. In addition, Lactobacillus and Lactococcus species were found to grow dominantly in fresh oyster gills under MA packaging, which supports the potential application of MA packaging for oyster storage. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of modified atmosphere packaging on 'Star Ruby' grapefruit phytochemicals.

PubMed

Chaudhary, Priyanka R; Jayaprakasha, G K; Porat, Ron; Patil, Bhimanagouda S

2015-01-28

Modified atmosphere packaging (MAP) can extend the shelf life of salads, vegetables, and fruits by generating a storage environment with low O2, high CO2, and high humidity. The current study investigates the effect of modified atmosphere and humidity generated by two plastic films, microperforated bags (MIPBs) and macroperforated bags (MAPBs), on the levels of phytochemicals present in 'Star Ruby' grapefruits (Citrus paradisi, Macf.) stored for 16 weeks at 10 °C. Control fruits were stored without any packaging film. Juice samples were analyzed every 4 weeks for ascorbic acid, carotenoids, limonoids, flavonoids, and furocoumarins and assessed for quality parameters. MAP significantly reduced weight loss compared to control grapefruits. Control fruits had more β-carotene, lycopene, and furocoumarin compared with the fruits in MAP. Flavonoid content was highest in fruits stored in MAPB (P < 0.05), while fruits stored in MIPB showed no significant difference in flavonoid content compared to control (P > 0.05). The MAP treatments did not significantly affect ascorbic acid, limonoids, or fruit quality parameters, including total soluble solids, acidity, ripening ratio, decay and disorders, fruit taste, and off-flavors after 16 weeks of storage. These results suggest that MAP can be used to maintain the quality of 'Star Ruby' grapefruit with no detrimental effect on health-promoting phytochemicals.

Influence of in-package cold plasma treatment on microbiological shelf life and appearance of fresh chicken breast fillets

USDA-ARS?s Scientific Manuscript database

The effect of in-package cold plasmas (CP) was studied on microbiological shelf life and surface lightness of fresh chicken fillets (pectoralis major) . chicken fillets were packaged in food trays in air or modified atmosphere (MA) gas (O2:CO2:N2 = 65:30:5) and stored at 4' after exposed to an in-pa...

Response of antioxidant activity and sensory quality in fresh-cut pear as affected by high O2,active packaging compared with low O2 packaging

USDA-ARS?s Scientific Manuscript database

Effects of active modified atmosphere packaging (MAP, initial O2/CO2: 5/5; 30/5; 80/0) and passive packaging (initial O2/CO2: 20.8/0 (air)) on the antioxidant capacity and sensory quality of fresh-cut ‘Yaoshan’ pear stored at 4C for 12 days were investigated. Samples stored in high O2 (30% and 80%) ...

Fresh meat packaging: consumer acceptance of modified atmosphere packaging including carbon monoxide.

PubMed

Grebitus, Carola; Jensen, Helen H; Roosen, Jutta; Sebranek, Joseph G

2013-01-01

Consumers' perceptions and evaluations of meat quality attributes such as color and shelf life influence purchasing decisions, and these product attributes can be affected by the type of fresh meat packaging system. Modified atmosphere packaging (MAP) extends the shelf life of fresh meat and, with the inclusion of carbon monoxide (CO-MAP), achieves significant color stabilization. The objective of this study was to assess whether consumers would accept specific packaging technologies and what value consumers place on ground beef packaged under various atmospheres when their choices involved the attributes of color and shelf life. The study used nonhypothetical consumer choice experiments to determine the premiums that consumers are willing to pay for extended shelf life resulting from MAP and for the "cherry red" color in meat resulting from CO-MAP. The experimental design allowed determination of whether consumers would discount foods with MAP or CO-MAP when (i) they are given more detailed information about the technologies and (ii) they have different levels of individual knowledge and media exposure. The empirical analysis was conducted using multinomial logit models. Results indicate that consumers prefer an extension of shelf life as long as the applied technology is known and understood. Consumers had clear preferences for brighter (aerobic and CO) red color and were willing to pay $0.16/lb ($0.35/kg) for each level of change to the preferred color. More information on MAP for extending the shelf life and on CO-MAP for stabilizing color decreased consumers' willingness to pay. An increase in personal knowledge and media exposure influenced acceptance of CO-MAP negatively. The results provide quantitative measures of how packaging affects consumers' acceptance and willingness to pay for products. Such information can benefit food producers and retailers who make decisions about investing in new packaging methods.

Antimicrobial (BN/PE) film combined with modified atmosphere packaging extends the shelf life of minimally processed fresh-cut iceberg lettuce.

PubMed

Kang, Sun-Chul; Kim, Min-Jeong; Park, In-Sik; Choi, Ung-Kyu

2008-03-01

This study was conducted to investigate the effect of modified atmosphere packaging (MAP) in combination with BN/PE film on the shelf life and quality of fresh-cut iceberg lettuce during cold storage. The total mesophilic population in the sample packed in BN/PE film under MAP conditions was dramatically reduced in comparison with that of PE film, PE film under MAP conditions, and BN/PE film. The O2 concentration in the BN/PE film under MAP conditions decreased slightly as the storage period progressed. The coloration of the iceberg lettuce progressed the slowest when it was packaged in BN/PE film under MAP conditions, followed by BN/PE film, PE film, and PE film under MAP conditions. The shelf life of fresh-cut iceberg lettuce packaged in the BN/PE film under MAP conditions was extended by more than 2 days at 10 degrees as compared with that of the BN/PE film in which the extension effect was more than 2 days longer than that of PE, PET, and OPP films.

The effect of different gas permeability of packaging on physicochemical and microbiological parameters of pork loin storage under high O2 modified atmosphere packaging conditions.

PubMed

Marcinkowska-Lesiak, Monika; Poławska, Ewa; Wierzbicka, Agnieszka

2017-03-01

The aim of this study was to determine the influence of different packaging materials on meat quality during cold storage. Therefore pork loins (m. longissimus thoracis et lumborum) obtained from crossbred pigs (Polish Landrance x Duroc, n = 6) were stored at 2 ℃ in modified atmosphere packs (80% O 2 , 20% CO 2 ) in four types of trays, which differ in gas permeability. Physicochemical (headspace gas composition, pH, colour, drip loss, cooking loss, shear force, the basic composition and fatty acid profile) and microbiological ( Salmonella spp., Escherichia coli, Enterobacteriaceae, total aerobic plates count, total psychrotrophic bacteria count, the number of lactic acid bacteria, Pseudomonas spp., the general amount of yeast and mold) parameters were monitored for up to 12 days. At the end of the storage period no differences in most physicochemical properties of pork loin due to type of packaging were found, however trays with high gas permeability had the greatest impact on total aerobic plates count and Pseudomonas spp. growth.

Quality changes of cuttlefish stored under various atmosphere modifications and vacuum packaging.

PubMed

Bouletis, Achilleas D; Arvanitoyannis, Ioannis S; Hadjichristodoulou, Christos; Neofitou, Christos; Parlapani, Foteini F; Gkagtzis, Dimitrios C

2016-06-01

Seafood preservation and its shelf life prolongation are two of the main issues in the seafood industry. As a result, and in view of market globalization, research has been triggered in this direction by applying several techniques such as modified atmosphere packaging (MAP), vacuum packaging (VP) and active packaging (AP). However, seafood such as octopus, cuttlefish and others have not been thoroughly investigated up to now. The aim of this research was to determine the optimal conditions of modified atmosphere under which cuttlefish storage time and consequently shelf life time could be prolonged without endangering consumer safety. It was found that cuttlefish shelf life reached 2, 2, 4, 8 and 8 days for control, VP, MAP 1, MAP 2 and MAP 3 (20% CO2 -80% N2 , 50% CO2 -50% N2 and 70% CO2 -30% N2 for MAP 1, 2 and 3, respectively) samples, respectively, judging by their sensorial attributes. Elevated CO2 levels had a strong microbiostatic effect, whereas storage under vacuum did not offer significant advantages. All physicochemical attributes of MAP-treated samples were better preserved compared to control. Application of high CO2 atmospheres such as MAP 2 and MAP 3 proved to be an effective strategy toward preserving the characteristics and prolonging the shelf life of fresh cuttlefish and thereby improving its potential in the market. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Potential mechanisms of carbon monoxide and high oxygen packaging in maintaining color stability of different bovine muscles.

PubMed

Liu, Chenglong; Zhang, Yimin; Yang, Xiaoyin; Liang, Rongrong; Mao, Yanwei; Hou, Xu; Lu, Xiao; Luo, Xin

2014-06-01

The objectives were to compare the effects of packaging methods on color stability, metmyoglobin-reducing-activity (MRA), total-reducing-activity and NADH concentration of different bovine muscles and to explore potential mechanisms in the enhanced color stability by carbon monoxide modified atmosphere packaging (CO-MAP, 0.4% CO/30% CO2/69.6% N2). Steaks from longissimus lumborum (LL), psoas major (PM) and longissimus thoracis (LT) packaged in CO-MAP, high-oxygen modified atmosphere packaging (HiOx-MAP, 80% O2/20% CO2) or vacuum packaging were stored for 0day, 4days, 9days, and 14days or stored for 9days then displayed in air for 0day, 1day, or 3days. The CO-MAP significantly increased red color stability of all muscles, and especially for PM. The PM and LT were more red than LL in CO-MAP, whereas PM had lowest redness in HiOx-MAP. The content of MetMb in CO-MAP was lower than in HiOx-MAP. Steaks in CO-MAP maintained a higher MRA compared with those in HiOx-MAP during storage. After opening packages, the red color of steaks in CO-MAP deteriorated more slowly compared with that of steaks in HiOx-MAP. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gas permeability and thermal behavior of polypropylene films used for packaging minimally processed fresh-cut potatoes: a case study.

PubMed

Siracusa, Valentina; Blanco, Ignazio; Romani, Santina; Tylewicz, Urszula; Dalla Rosa, Marco

2012-10-01

This work reports an experimental study on the permeability and thermal behavior of commercial polypropylene (PP) film used for fresh-cut potatoes packaging. The permeability was tested using oxygen, carbon dioxide, nitrogen, mix of these 3 gases, normally used for modified atmosphere packaging (MAP) and Air, to understand if it would be possible to extend the shelf life of this food product designed for the catering field in respect to the packaging behavior. The temperature influence on permeability data, from 5 to 40 °C, was analyzed, before and after 4, 8, 12, 15, and 20 d of food contact, pointing out the dependence between temperature and gas transmission rate (GTR), solubility (S), diffusion coefficient (D), and time lag (t(L)) parameters. The activation energies (E) of the permeation process were determined with the different gases used in the experiments. The thermal behavior of PP film was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) to well understand its thermal stability. Fourier transformed-infrared with attenuated total reflectance (FT-IR/ATR) spectroscopy was also performed in order to study the influence of the food contact on the chemical characteristics of the polymer film. The results obtained were discussed and compared each other. Studied samples showed, for all investigated gases, an increase of gas permeability and S values at higher temperature. Heat resistance classification among the sample as it is and stored in modified atmospheres was made. Finally all performed experiments have showed good polymer stability for the shelf-life storage potatoes under study. Study of packaging material was performed in a range of temperature, which can simulate the service condition to assess the suitability of a commercial polymer film for modified atmosphere packaging of fresh-cut potatoes minimally processed designed for catering purpose. © 2012 Institute of Food Technologists®

Predictive model for the growth of spoilage bacteria on modified atmosphere packaged Atlantic salmon produced in Australia.

PubMed

Powell, S M; Ratkowsky, D A; Tamplin, M L

2015-05-01

Most existing models for the spoilage of modified atmosphere packed Atlantic salmon are based on the growth of the spoilage organism Photobacterium phosphoreum. However, there is evidence that this organism is not the specific spoilage organism on salmon produced and packaged in Australia. We developed a predictive model for the growth of bacteria in Australian-produced Atlantic salmon stored under modified atmosphere conditions (30-98% carbon dioxide in nitrogen) at refrigeration temperatures (0-10 °C). As expected, both higher levels of carbon dioxide and lower temperatures decreased the observed growth rates of the total population. A Bělehrádek-type model for growth rate fitted the data best with an acceptably low root mean square error. At low temperatures (∼0 °C) the growth rates in this study were similar to those predicted by other models but at higher temperatures (∼10 °C) the growth rates were significantly lower in the current study. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Effect of irradiation, active and modified atmosphere packaging, container oxygen barrier and storage conditions on the physicochemical and sensory properties of raw unpeeled almond kernels (Prunus dulcis).

PubMed

Mexis, Stamatios F; Riganakos, Kyriakos A; Kontominas, Michael G

2011-03-15

The present study investigated the effect of irradiation, active and modified atmosphere packaging, and storage conditions on quality retention of raw, whole, unpeeled almonds. Almond kernels were packaged in barrier and high-barrier pouches, under N(2) or with an O(2) absorber and stored either under fluorescent lighting or in the dark at 20 °C for 12 months. Quality parameters monitored were peroxide value, hexanal content, colour, fatty acid composition and volatile compounds. Of the sensory attributes colour, texture, odour and taste were evaluated. Peroxide value and hexanal increased with dose of irradiation and storage time. Irradiation resulted in a decrease of polyunsaturated and monounsaturated fatty acids during storage with a parallel increase of saturated fatty acids. Volatile compounds were not affected by irradiation but increased with storage time indicating enhanced lipid oxidation. Colour parameters of samples remained unaffected immediately after irradiation. For samples packaged under a N(2) , atmosphere L and b values decreased during storage with a parallel increase of value a resulting to gradual product darkening especially in irradiated samples. Non-irradiated almonds retained acceptable quality for ca. 12 months stored at 20 °C with the O(2) absorber irrespective of lighting conditions and packaging material oxygen barrier. The respective shelf life for samples irradiated at 1.0 kGy was 12 months packaged in PET-SiOx//LDPE irrespective of lighting conditions and 12 months for samples irradiated at 3 kGy packaged in PET-SiOx//LDPE stored in the dark. Copyright © 2010 Society of Chemical Industry.

Effect of a nano-silver coating on the quality of fresh turkey meat during storage after modified atmosphere or vacuum packaging.

PubMed

Deus, D; Kehrenberg, C; Schaudien, D; Klein, G; Krischek, C

2017-02-01

Nano-silver is used in consumer products due to its antibacterial properties. The aim of this study was to evaluate the effect of a nano-silver-coated film on the quality of turkey meat during vacuum-sealed and modified atmosphere packaging up to 12 days of storage. In the first part of the experiment, turkey breasts were packaged using either vacuum packaging or modified atmosphere packages (MAPs) and contained films with or without a nano-silver coating (control film). Parameters such as pH, electrical conductivity, color (lightness L*, redness a*), myoglobin redox forms, thiobarbituric acid-reactive substances (TBARS), biogenic amines (BAs), total viable bacterial counts, Pseudomonas species counts, and Enterobacteriaceae species counts were evaluated on storage days 4, 8, and 12. In the second part of the study, the antimicrobial effect of a nano-silver-coated film on turkey breast was evaluated after inoculation with Escherichia coli (E. coli). Turkey meat packaged with the nano-silver film exhibited lower a* values on days 1 (3.15 ± 0.62), 4 (3.90 ± 0.68), and 8 (4.27 ± 0.76) compared to the packaged meat with the control film (3.41 ± 0.73, 4.35 ± 0.94, 4.85 ± 0.89, respectively), indicating special optical properties of nanoparticles. Concerning the BAs, silver packaged meat showed higher values of tyramine on day 12 (1274 ± 392 ng/g meat) and cadaverine on day 4 (1224 ± 435 ng/g meat) compared to the normal packaged products (647 ± 576 and 508 ± 314 ng/g meat, respectively). MAP meat revealed higher L* and TBARS values and lower microbial counts than the vacuum packaged products on all days. The MAP meat also showed lower a* results on days 4 and 8 and higher metmyoglobin (metMb) values on days 8 and 12 compared to th E: vacuum products. In the inoculation study, the microbial counts of the turkey meat were comparable between the two film types. The study showed that the nano-silver coating did not exhibit any advantageous effects on the quality and microbiological parameters of the turkey meat. © 2016 Poultry Science Association Inc.

Modified atmosphere packaging and vacuum packaging for long period chilled storage of dry-cured Iberian ham.

PubMed

Parra, V; Viguera, J; Sánchez, J; Peinado, J; Espárrago, F; Gutierrez, J I; Andrés, A I

2010-04-01

Dry-cured Iberian ham slices were stored under vacuum and under four different modified atmospheres (60/40=60%N(2)+40%CO(2); 70/30=70%N(2)+30%CO(2); 80/20=80%N(2)+20%CO(2); argon=70%argon+30%CO(2)) at 4+/-1 degrees C during 120 days. Gas composition, moisture content, pH, colour, pigment content, and lipid stability were measured, as well as sensory and microbial analysis were carried out throughout storage. A loss of intensity of red colour (a(*)-values) was observed during storage in ham slices (P<0.05). Consistently, MbFe(II)NO content also decreased throughout storage (P>0.05). Slices of ham packed in 40%CO(2) (60/40) and 30%CO(2) (70/30) showed lower a(*)-values than the rest of the batches after 60 days (P<0.05), though differences were not evident after 120 days (P>0.05). TBARs values showed an upward trend during the storage of packaged slices (P<0.05). Vacuum-packed slices showed the lowest TBARs values and those packed with 40%CO(2), the highest. Sensory attributes did not vary significantly (P>0.05) throughout storage under refrigeration and packed either in vacuum or in modified atmospheres. No safety problems were detected in relation to the microbial quality in any case. 2009 Elsevier Ltd. All rights reserved.

Low Temperature and Modified Atmosphere: Hurdles for Antibiotic Resistance Transfer?

PubMed

Van Meervenne, Eva; Van Coillie, Els; Van Weyenberg, Stephanie; Boon, Nico; Herman, Lieve; Devlieghere, Frank

2015-12-01

Food is an important dissemination route for antibiotic-resistant bacteria. Factors used during food production and preservation may contribute to the transfer of antibiotic resistance genes, but research on this subject is scarce. In this study, the effect of temperature (7 to 37°C) and modified atmosphere packaging (air, 50% CO2-50% N2, and 100% N2) on antibiotic resistance transfer from Lactobacillus sakei subsp. sakei to Listeria monocytogenes was evaluated. Filter mating was performed on nonselective agar plates with high-density inocula. A more realistic setup was created by performing modified atmosphere experiments on cooked ham using high-density and low-density inocula. Plasmid transfer was observed between 10 and 37°C, with plasmid transfer also observed at 7°C during a prolonged incubation period. When high-density inocula were used, transconjugants were detected, both on agar plates and cooked ham, under the three atmospheres (air, 50% CO2-50% N2, and 100% N2) at 7°C. This yielded a median transfer ratio (number of transconjugants/number of recipients) with an order of magnitude of 10(-4) to 10(-6). With low-density inocula, transfer was only detected under the 100% N2 atmosphere after 10-day incubation at 7°C, yielding a transfer ratio of 10(-5). Under this condition, the highest bacterial density was obtained. The results indicate that low temperature and modified atmosphere packaging, two important hurdles in the food industry, do not necessarily prevent plasmid transfer from Lactobacillus sakei subsp. sakei to Listeria monocytogenes.

Bacterial communities of fresh goat meat packaged in modified atmosphere.

PubMed

Carrizosa, Elia; Benito, María José; Ruiz-Moyano, Santiago; Hernández, Alejandro; Villalobos, Maria Del Carmen; Martín, Alberto; Córdoba, María de Guía

2017-08-01

The objective of this work was to study the growth and development of fortuitous flora and food pathogens in fresh goat meat packaged under modified atmospheres containing two different concentrations of CO 2 . Meat samples were stored at 10 °C under two different modified-atmosphere packing (MAP) conditions: treatment A had 45% CO 2  + 20% O 2  + 35% N 2 and treatment B had 20% CO 2  + 55% O 2  + 25% N 2 . During 14 days of storage, counts of each bacterial group and dominant species identification by 16S rRNA gene sequencing were performed to determine the microbial diversity present. The MAP condition used for treatment A was a more effective gas mixture for increasing the shelf life of fresh goat meat, significantly reducing the total number of viable bacteria and enterobacteria counts. Members of the Enterobacteriaceae family were the most common contaminants, although Hafnia alvei was dominant in treatment A and Serratia proteamaculans in treatment B. Identification studies at the species level showed that different microorganisms develop under different storage conditions, reflecting the importance of gas composition in the modified atmosphere on the bacterial community. This work provides new insights into the microbial changes of goat meat storage under different MAP conditions, which will be beneficial for the meat industry. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of Low-Oxygen Environments on the Radiation Tolerance of the Cabbage Looper Moth (Lepidoptera: Noctuidae).

PubMed

Condon, Catriona H; White, Sabrina; Meagher, Robert L; Jeffers, Laura A; Bailey, Woodward D; Hahn, Daniel A

2017-02-01

Ionizing radiation is used as a phytosanitary treatment to mitigate risks from invasive species associated with trade of fresh fruits and vegetables. Commodity producers prefer to irradiate fresh product stored in modified atmosphere packaging that increases shelf life and delays ripening. However, irradiating insects in low oxygen may increase radiation tolerance, and regulatory agencies are concerned modified atmosphere packaging will decrease efficacy of radiation doses. Here, we examined how irradiation in a series of oxygen conditions (0.1-20.9 kPa O2) alters radiotolerance of larvae and pupae of a model lepidopteran Trichoplusia ni (Hubner) (Diptera: Noctuidae). Irradiating in severe hypoxia (0.1 kPa O2) increased radiation tolerance of insects compared with irradiating in atmospheric oxygen (20.9 kPa O2). Our data show irradiating pharate adult pupae at 600 Gy in moderately severe hypoxia (5 kPa O2) increased adult emergence compared with irradiation in atmospheric oxygen (20.9 kPa O2). Our data also show that in one of the three temporal replicates, irradiating T. ni larvae in moderately severe hypoxia (5 kPa O2) can also increase radiotolerance at an intermediate radiation dose of 100 Gy compared with irradiating in atmospheric oxygen conditions, but not at higher or lower doses. We discuss implications of our results in this model insect for the current generic doses for phytosanitary irradiation, including the recently proposed 250 Gy generic dose for lepidioptera larvae, and temporary restriction on irradiating commodities in modified atmosphere packaging that reduces the atmosphere to < 18 kPa O2. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effect of residual oxygen on colour stability during chill storage of sliced, pasteurised ham packaged in modified atmosphere.

PubMed

Møller, J K; Jensen, J S; Olsen, M B; Skibsted, L H; Bertelsen, G

2000-04-01

The critical level of residual oxygen to avoid light induced oxidative discoloration during chill storage of sliced, pasteurised ham packaged in modified atmosphere (20% carbon dioxide balanced with nitrogen in a 1:3 product to headspace volume ratio) was found to lie between 0.1 and 0.5% oxygen. In 0.5% oxygen light induced discoloration was significant, as detected by the tristimulus colorimetry redness parameter, when compared to the same product stored in the dark, while at 0.1 and 0.02% oxygen the colour was stable both in the dark and when exposed to light for up to 27 days in chill storage. Lipid oxidation, determined as 2-thiobarbituric acid-reactive substances, and total plate counts showed no difference between discoloured and colour stable products, although a trained panel in a triangle test could differentiate between the taste of ham from packages with 0.02 and 0.5% oxygen after 27 days of chill storage.

Effect of packaging atmospheres on storage quality characteristics of heavily marbled beef longissimus steaks.

PubMed

Yang, Xiaoyin; Zhang, Yimin; Zhu, Lixian; Han, Mingshan; Gao, Shujuan; Luo, Xin

2016-07-01

The objective of this study was to investigate the effects of modified atmosphere packaging (MAP) systems on shelf-life and quality of beef steaks with high marbling. Four packaging types were used including 80% O2 MAP (80% O2+20% CO2), 50% O2 MAP (50% O2+30% CO2+20% N2), carbon monoxide MAP (0.4% CO+30% CO2+69.6% N2) and vacuum packaging (VP). Steaks were displayed under simulated retail conditions at 4°C for 12days. Purge loss, pH, color stability, oxidative stability and microbial counts were monitored. Aerobically packaged steaks exhibited a bright-red color at the first 4days. However, discoloration and oxidation became major factors limiting their shelf-life to 8days. Compared with aerobic packaging, anaerobic packaging extended shelf-life of heavily marbled beef steaks, due to better color stability, together with lower oxidation and microbial populations. Among all packaging methods, CO-MAP had the best preservation for steaks, with more red color than other packaging types. Copyright © 2016 Elsevier Ltd. All rights reserved.

The AIROPA software package: milestones for testing general relativity in the strong gravity regime with AO

NASA Astrophysics Data System (ADS)

Witzel, Gunther; Lu, Jessica R.; Ghez, Andrea M.; Martinez, Gregory D.; Fitzgerald, Michael P.; Britton, Matthew; Sitarski, Breann N.; Do, Tuan; Campbell, Randall D.; Service, Maxwell; Matthews, Keith; Morris, Mark R.; Becklin, E. E.; Wizinowich, Peter L.; Ragland, Sam; Doppmann, Greg; Neyman, Chris; Lyke, James; Kassis, Marc; Rizzi, Luca; Lilley, Scott; Rampy, Rachel

2016-07-01

General relativity can be tested in the strong gravity regime by monitoring stars orbiting the supermassive black hole at the Galactic Center with adaptive optics. However, the limiting source of uncertainty is the spatial PSF variability due to atmospheric anisoplanatism and instrumental aberrations. The Galactic Center Group at UCLA has completed a project developing algorithms to predict PSF variability for Keck AO images. We have created a new software package (AIROPA), based on modified versions of StarFinder and Arroyo, that takes atmospheric turbulence profiles, instrumental aberration maps, and images as inputs and delivers improved photometry and astrometry on crowded fields. This software package will be made publicly available soon.

Effect of nitrogen gas packaging on the quality and microbial growth of fresh-cut vegetables under low temperatures.

PubMed

Koseki, Shigenobu; Itoh, Kazuhiko

2002-02-01

Nitrogen (N2) gas packaging for fresh-cut vegetables (lettuce and cabbage) has been examined as a means of modified atmosphere packaging (MAP) for extending the shelf life of cut vegetables. Gas composition in enclosed packages that contained cut vegetables and were filled with 100% N2 had an oxygen (O2) concentration of 1.2 to 5.0% and a carbon dioxide (CO2) concentration of 0.5 to 3.5% after 5 days of storage. An atmosphere of low concentrations of O2 and high CO2 conditions occurred naturally in the package filled with N2 gas. Degradation of cut vegetables in terms of appearance was delayed by N2 gas packaging. Because of this effect, the appearance of fresh-cut vegetables packaged with N2 gas remained acceptable at temperatures below 5 degrees C after 5 days. Treatment with acidic electrolyzed water (AcEW) contributed to the acceptability of the vegetables' appearance at 5 and 10 degrees C in the air-packaging system. N2 gas packaging did not significantly affect the growth of microbial populations (total aerobic bacteria, coliform bacteria, Bacillus cereus, and psychrotrophic bacteria) in or on cut vegetables at 1, 5, and 10 degrees C for 5 days. Microbial growth in or on the cut vegetables was inhibited at 1 degrees C for 5 days regardless of atmospheric conditions.

Development of Multifunctional Active Film and Its Application in Modified Atmosphere Packaging of Shiitake Mushrooms.

PubMed

Wang, Hong Jiang; An, Duck Soon; Lee, Dong Sun

2016-09-01

Agar-based films with multiple functions (CO 2 absorption, water vapor absorption, and antimicrobial activity) were developed, tested for their properties, and then applied to the packaging of fresh shiitake mushrooms as an insert label. The films were cast from an agar-based aqueous solution containing a dissolving plasticizer (glycerol), a CO 2 absorbent (sodium carbonate [SC] alone or a combination of SC and sodium glycinate [SC-SG]), and a volatile antimicrobial agent (carvacrol [CRV]). The agar of the film matrix is designed to serve as a water vapor absorbent. The multifunctional films tended to have poor mechanical properties, with a hard texture and an opaque and yellowish color. The CO 2 absorbent, either SC alone or SC-SG, affected CRV retention and release along with the CO 2 and water vapor absorption behavior. Both films (SC-CRV and SC-SG-CRV films) showed good inhibitory effects against Pseudomonas fluorescens and Saccharomyces cerevisiae . SC-CRV film had a higher and faster CO 2 absorption property, higher retention and extended release of CRV, and lower and slower water vapor absorption and was assessed to be better suited for use in shiitake mushroom packaging. The packaging in which the SC-CRV film with an appropriate amount of CRV was used as an insert label was able to generate the desired atmosphere and less moisture condensation inside the package, producing the best preservation of quality in terms of mushroom color, firmness, flavor score, and microbial counts after 6 days of storage at 10°C. A tailored modified atmosphere packaging system using multifunctional film would be useful in the preservation of CO 2 -sensitive fresh commodities.

Identification and growth dynamics of meat spoilage microorganisms in modified atmosphere packaged poultry meat by MALDI-TOF MS.

PubMed

Höll, Linda; Behr, Jürgen; Vogel, Rudi F

2016-12-01

Modified atmosphere packaging (MAP) is widely used in food industry to extend the microbiological shelf-life of meat. Typically, poultry meat has been packaged in a CO2/N2 atmosphere (with residual low O2). Recently, some producers use high O2 MAP for poultry meat to empirically reach comparable shelf lifes. In this work, we compared spoilage microbiota of skinless chicken breast in high (80% O2, 20% CO2) and low O2 MAP (65% N2 and 35% CO2). Two batches of meat were incubated in each atmosphere for 14 days at 4 °C and 10 °C. Atmospheric composition of each pack and colony forming units (25 °C, 48 h, BHI agar) of poultry samples were determined at seven timepoints. Identification of spoilage organisms was carried out by MALDI-TOF MS. Brochothrix thermosphacta, Carnobacterium sp. and Pseudomonas sp. were the main organisms found after eight days at 4 °C and 10 °C in high O2 MAP. In low O2 MAP, the main spoilage microbiota was represented by species Hafnia alvei at 10 °C, and genera Carnobacterium sp., Serratia sp., and Yersinia sp. at 4 °C. High O2 MAP is suggested as preferential gas because were less detrimental and pathogens like Yersinia were not observed. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect on turkey meat shelf life of modified-atmosphere packaging with an argon mixture.

PubMed

Fraqueza, M J; Barreto, A S

2009-09-01

There is a lack of knowledge related to the action of Ar on microbial development and prevention of oxidation when applied to raw meat under modified-atmosphere package (MAP). The aim of this study was to evaluate the effect of an anaerobic gas mixture with Ar on spoilage flora growth, color, and lipid oxidation stability of turkey meat under MAP stored at 0 degrees C. Breast muscles samples were collected on different working days from turkey carcasses (BUT9 and BIG6), fast-cooled in a tunnel (-2 degrees C, 2 m.s(-1), 90% RH) for 2 h and selected to be deboned according current practices in industrial slaughterhouses. The breasts were cut into slices that were individually packaged under aerobiosis (P0) and in 4 different modified atmospheres containing different gas mixtures as (P1) 100% N2, (P2) 50% Ar-50% N2, (P3) 50% Ar-50% CO2, and (P4) 50% N2-50% CO2. All samples were stored at 0+/-1 degrees C in the dark for between 12 and 25 d. Meat samples packaged in P0 were analyzed for their microbial and physicochemical characteristics on d 0, 5, and 12 of storage and then extended to 19 and 25 d when samples were under MAP. The microbial shelf life period extension of MAP sliced turkey meat compared with aerobic packaging (5-d shelf life) is 1 wk more for P1 and P2 mixtures, 2 wk for P4, and 3 wk for P3. The Ar-CO2 mixture was more efficient in delaying flora development than CO2-N2 with 1 log difference on the 25th day of storage, for total psychrotrophic counts, total anaerobic counts, and Brochothrix thermosphacta. The presence of Ar on gas mixtures did not seem to have any additional protective effect on lipid turkey meat oxidation.

Effects of ethrel, 1-MCP and modified atmosphere packaging on the quality of 'Wonderful' pomegranates during cold storage.

PubMed

Valdenegro, Mónika; Huidobro, Camila; Monsalve, Liliam; Bernales, Maricarmen; Fuentes, Lida; Simpson, Ricardo

2018-03-24

Pomegranate (Punica granatum) is a non-climacteric fruit susceptible to chilling injury (CI) at temperatures below 5 °C. To understand the influences of ethylene and modified atmosphere on CI physiological disorders of pomegranate, exogenous ethrel (0.5, 1 and 1.5 µg L -1 ) treatments, 1-methylcyclopropene (1-MCP) (1 µL L -1 ) exposure, packaging in a modified atmosphere (MAP) (XTend™ bags; StePac, São Paulo, Brazil), a MAP/1-MCP combination, and packaging in macro-perforated bags (MPB) were applied. The treated fruits were cold stored (2 ± 1 °C; 85% relative humidity) and sampled during 120 + 3 days at 20 °C. During cold storage, CI symptoms started at 20 days in MPB and at 60 days for all exogenous ethylene treatments, and were delayed to 120 days in MAP, 1-MCP and MAP/1-MCP treatments. MPB and ethylene treatments induced significant electrolyte leakage, oxidative damage, lipid peroxidation, ethylene and CO 2 production, and 1-aminocyclopropane-1-carboxylic acid oxidase activity, without any change in total soluble solids, titratable acidity or skin and aril colours. Conversely, MAP by itself, or in combination with 1-MCP application, effectively delayed CI symptoms. During long-term cold storage of this non-climacteric fruit, ethrel application induced endogenous ethylene biosynthesis, accelerating the appearance of CI symptoms in contrast to the observations made for MAP and 1-MCP treatments. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

An adapted isolation procedure reveals Photobacterium spp. as common spoilers on modified atmosphere packaged meats.

PubMed

Hilgarth, M; Fuertes-Pèrez, S; Ehrmann, M; Vogel, R F

2018-04-01

The genus Photobacterium comprises species of marine bacteria, commonly found in open-ocean and deep-sea environments. Some species (e.g. Photobacterium phosphoreum) are associated with fish spoilage. Recently, culture-independent studies have drawn attention to the presence of photobacteria on meat. This study employed a comparative isolation approach of Photobacterium spp. and aimed to develop an adapted isolation procedure for recovery from food samples, as demonstrated for different meats: Marine broth is used for resuspending and dilution of food samples, followed by aerobic cultivation on marine broth agar supplemented with meat extract and vancomycin at 15°C for 72 h. Identification of spoilage-associated microbiota was carried out via Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry using a database supplemented with additional mass spectrometry profiles of Photobacterium spp. This study provides evidence for the common abundance of multiple Photobacterium species in relevant quantities on various modified atmosphere packaged meats. Photobacterium carnosum was predominant on beef and chicken, while Photobacterium iliopiscarium represented the major species on pork and Photobacterium phosphoreum on salmon, respectively. This study demonstrates highly frequent isolation of multiple photobacteria (Photobacterium carnosum, Photobacterium phosphoreum, and Photobacterium iliopiscarium) from different modified-atmosphere packaged spoiled and unspoiled meats using an adapted isolation procedure. The abundance of photobacteria in high numbers provides evidence for the hitherto neglected importance and relevance of Photobacterium spp. to meat spoilage. © 2018 The Society for Applied Microbiology.

Maintenance of safety and quality of refrigerated ready-to-cook seasoned ground beef product (meatball) by combining gamma irradiation with modified atmosphere packaging.

PubMed

Gunes, Gurbuz; Ozturk, Aylin; Yilmaz, Neriman; Ozcelik, Beraat

2011-08-01

Meatballs were prepared by mixing ground beef and spices and inoculated with E. coli O157:H7, L. monocytogenes, and S. enteritidis before packaged in modified atmosphere (3% O₂ + 50% CO₂ + 47% N₂) or aerobic conditions. The packaged samples were irradiated at 0.75, 1.5, and 3 kGy doses and stored at 4 °C for 21 d. Survival of the pathogens, total plate count, lipid oxidation, color change, and sensory quality were analyzed during storage. Irradiation at 3 kGy inactivated all the inoculated (approximately 10⁶ CFU/g) S. enteritidis and L. monocytogenes cells in the samples. The inoculated (approximately 10⁶ CFU/g) E. coli O157:H7 cells were totally inactivated by 1.5 kGy irradiation. D¹⁰-values for E. coli O157:H7, S. enteritidis, and L. monocytogenes were 0.24, 0.43, and 0.41 kGy in MAP and 0.22, 0.39, and 0.39 kGy in aerobic packages, respectively. Irradiation at 1.5 and 3 kGy resulted in 0.13 and 0.36 mg MDA/kg increase in 2-thiobarbituric acid-reactive substances (TBARS) reaching 1.02 and 1.49 MDA/kg, respectively, on day 1. Irradiation also caused significant loss of color and sensory quality in aerobic packages. However, MAP effectively inhibited the irradiation-induced quality degradations during 21-d storage. Thus, combining irradiation (3 kGy) and MAP (3% O₂ + 50% CO₂ + 47% N₂) controlled the safety risk due to the potential pathogens and maintained qualities of meatballs during 21-d refrigerated storage. Combined use of gamma irradiation and modified atmosphere packaging (MAP) can maintain quality and safety of seasoned ground beef (meatball). Seasoned ground beef can be irradiated at 3 kGy and packaged in MAP with 3% O₂ + 50% CO₂ + 47% N₂ gas mixture in a high barrier packaging materials. These treatments can significantly decrease risk due to potential pathogens including E. coli O157:H7, L. monocytogenes, and S. enteritidis in the product. The MAP would reduce the undesirable effects of irradiation on quality, and extend the shelf life of the product for up to 21 d at 3 °C. © 2011 Institute of Food Technologists®

Effect of Rosmarinus officinalis L. essential oil combined with different packaging conditions to extend the shelf life of refrigerated beef meat.

PubMed

Sirocchi, Veronica; Devlieghere, Frank; Peelman, Nanou; Sagratini, Gianni; Maggi, Filippo; Vittori, Sauro; Ragaert, Peter

2017-04-15

Rosemary essential oil (REO) contains bioactives having antioxidant and antimicrobial properties. This work investigated the effect of REO combined with modified atmosphere packaging conditions (MAP), in our case, aerobic, vacuum or high O 2 , to extend the shelf life of beef. Beef slices were wrapped in special three-layer sheets of packaging material, some with a coating of REO (active packaging, AP), and some without REO (non active packaging, NAP), and stored at 4°C for 20days. The use of REO proved efficacious in every storage condition, as seen in the lower counts of psychrotrophics, Brochothrix thermosphacta, Pseudomonas spp., and Enterobacteriaceae in AP meat compared to NAP meat. Sensory and colourimetric analyses showed that the best packaging conditions were high-O 2 atmosphere in combination with REO. Based on microbiological data, shelf life of beef was 5-6days for AP samples packaged under aerobic conditions and 14-15days for AP samples in high-O 2 conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Shelf-life extension of semi-dried buckwheat noodles by the combination of aqueous ozone treatment and modified atmosphere packaging.

PubMed

Bai, Yi-Peng; Guo, Xiao-Nao; Zhu, Ke-Xue; Zhou, Hui-Ming

2017-12-15

The present study investigated the combined effects of aqueous ozone treatment and modified atmosphere packaging (MAP) on prolonging the shelf-life of semi-dried buckwheat noodles [SBWN; moisture content (22.5±0.5%)] at 25°C. Firstly, the different concentrations of ozonated water were used to make SBWN. Subsequently, SBWN prepared with ozonated water were packaged under six different conditions and stored for 11days. Changes in microbial, chemical-physical, textural properties and sensorial qualities of SWBN were monitored during storage. Microbiological results indicated that adopting 2.21mg/L of ozonated water resulted in a 1.8 log 10 CFU/g reduction of the initial microbial loads in SBWN. In addition, MAP suppressed the microbial growth with a concomitant reduction in the rates of acidification and quality deteriorations of SBWN. Finally, the shelf-life of sample packed under N 2 :CO 2 =30:70 was extended to 9days, meanwhile textural and sensorial characteristics were maintained during the whole storage period. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sweet cherries from farm to table: A review.

PubMed

Habib, Muzammil; Bhat, Mudassir; Dar, B N; Wani, Ali Abas

2017-05-24

In order to enable long-distance transportation and ensure that the fruit presents the requisite quality on arrival at markets, the cherry industry for direct consumption needs to prolong post-harvest shelf life. Sweet cherries are highly perishable, non-climacteric fruits with shelf life of 7-14 days in cold storage. Their shelf life is shortened by loss of firmness, color and flavor, stem discoloration, desiccation and mould growth. Various factors such as harvest time, proper handling and cooling practices and above all packaging, greatly influence the shelf life of cherries. One of the areas of research that has shown promise, and had success, is modified atmosphere packaging (MAP). It is one of the fastest growing packaging technologies and has many advantages for different food products. Properly designed modified atmosphere packs can be exploited to lower respiration rates and thus ripening of fruits which results in least changes in physiochemical parameters of sweet cherries during postharvest storage. This paper intended to review a broad spectrum of studies dealt with the use of MAP for preservation of sweet cherries cultivars with an interest for future research work.

Effect of integration of oxalic acid and hot water treatments on postharvest quality of rambutan (Nephelium lappaceum L. cv. Anak Sekolah) under modified atmosphere packaging.

PubMed

Hafiz, Ahmad Faiz Ahmad; Keat, Yeoh Wei; Ali, Asgar

2017-06-01

The shelf life of rambutan is often limited due to rapid water loss from the spinterns and browning of the pericarp. An integrated approach, which combined hot water treatment (HWT) (56 °C for 1 min), oxalic acid (OA) dip (10% for 10 min) and modified atmosphere packaging (MAP), was used to study their effectiveness on the quality of rambutan during storage (10 °C, 90-95% relative humidity). Significant differences were observed in rambutan quality with the combination of MAP + HWT + OA after 20 days of storage. This treatment combination resulted into better retention of firmness and colour (L and a* values) than in the control. Change in the total soluble solid content was significantly delayed however the titratable acidity showed no significant change in comparison to the control at the end of storage.

Influence of modified atmosphere and varying time in storage on the irradiation sensitivity of Salmonella on sliced roma tomatoes

NASA Astrophysics Data System (ADS)

Niemira, Brendan A.; Boyd, Glenn

2013-09-01

Salmonella contamination of tomatoes is a recurrent food safety concern. Irradiation inactivates pathogens on fresh and fresh cut produce. However, the interaction of time in refrigerated storage and modified atmosphere packaging (MAP) may influence the response of pathogens to irradiation. Roma tomatoes were sliced and inoculated with a cocktail of outbreak strains of Salmonella. The inoculated tomatoes were packaged under one of four atmospheres: air, 10/90 O2/N2, 5/95 O2/N2 or 100% N2. The packages were kept in refrigerated storage (10 °C) for various times after inoculation, to simulate the potential time delay between packaging and irradiation treatment. Tomatoes were irradiated immediately (0 h), or after 24 or 48 h in storage. The surviving populations were recovered and enumerated. Irradiation effectively reduced Salmonella at all times. Estimated D10 value (the dose necessary for 1 log reduction) varied significantly among the combinations of time and MAP, ranging from 0.165-0.335 kGy. Tomatoes packaged in air, irradiated at 0 h, had a D10 of 0.165 kGy; all other combinations showed significantly higher D10. Reduced oxygen generally resulted in higher D10 values, with the highest D10 of 0.335 kGy obtained for 100% N2, 0 h. Time in storage pre-irradiation tended to increase D10 for air and 5/95 O2/N2, but not for 10/90 O2/N2 or 100% N2. These results suggest that time required for refrigerated holding of processed Roma tomatoes or shipment to an off-site irradiation service provider may alter the efficacy of irradiation if reduced oxygen MAP is used.

Characterization of spoilage markers in modified atmosphere packaged iceberg lettuce.

PubMed

Ioannidis, Angelos-Gerasimos; Kerckhof, Frederiek-Maarten; Riahi Drif, Yasmine; Vanderroost, Mike; Boon, Nico; Ragaert, Peter; De Meulenaer, Bruno; Devlieghere, Frank

2018-04-22

Fresh cut iceberg lettuce spoilage was studied considering the microbial and biochemical activity, the formation of volatile organic compounds (VOC) and consumer acceptability. Lettuce was packaged under three different packaging conditions and stored at 4 °C for 10 days: anaerobic packaging (ANAER), equilibrium modified atmosphere packaging with 3% O 2 (EMAP) and perforated packages (AIR). Results indicated a clear distinction between packaging conditions. EMAP and AIR resulted in a short shelf life (≤5.6 days) which was limited due to browning, leading to consumer rejection as assessed via the Weibull hazard analysis method, while no off-odors were detected. Culture- independent 16 s rRNA gene amplicon sequencing revealed Pseudomonas spp. as the dominating species. In contrast, under ANAER conditions, lactic acid bacteria dominated with genera of Leuconostoc spp. and Lactococcus spp. proliferating, while also oligotypes of Pseudomonas spp. were found. Spoilage under ANAER occurred after 6.6 days and it was related to strong fermentative-like off-odors that were present by the end of storage. As revealed by selective ion flow tube mass spectrometry (SIFT-MS), these odors were associated with several VOCs such as: ethanol, 3-methyl-1-butanol, 2,3-butanediol, (Z)-3-hexen-1-ol, hexanal, acetic acid, ethyl acetate and dimethyl sulfide. Panelists rejected the iceberg lettuce due to the formation of off-odors while the overall appearance remained good throughout the study. Hence a sensor based technology incorporated in the packaging, detecting VOCs and in particular ethanol as dominant compound, could serve as a spoilage indicator for ANAER packed lettuce, which proved to have the longest shelf life. Copyright © 2018 Elsevier B.V. All rights reserved.

Exploring lot-to-lot variation in spoilage bacterial communities on commercial modified atmosphere packaged beef.

PubMed

Säde, Elina; Penttinen, Katri; Björkroth, Johanna; Hultman, Jenni

2017-04-01

Understanding the factors influencing meat bacterial communities is important as these communities are largely responsible for meat spoilage. The composition and structure of a bacterial community on a high-O 2 modified-atmosphere packaged beef product were examined after packaging, on the use-by date and two days after, to determine whether the communities at each stage were similar to those in samples taken from different production lots. Furthermore, we examined whether the taxa associated with product spoilage were distributed across production lots. Results from 16S rRNA amplicon sequencing showed that while the early samples harbored distinct bacterial communities, after 8-12 days storage at 6 °C the communities were similar to those in samples from different lots, comprising mainly of common meat spoilage bacteria Carnobacterium spp., Brochothrix spp., Leuconostoc spp. and Lactococcus spp. Interestingly, abundant operational taxonomic units associated with product spoilage were shared between the production lots, suggesting that the bacteria enable to spoil the product were constant contaminants in the production chain. A characteristic succession pattern and the distribution of common spoilage bacteria between lots suggest that both the packaging type and the initial community structure influenced the development of the spoilage bacterial community. Copyright © 2016 Elsevier Ltd. All rights reserved.

Controlling Brochothrix thermosphacta as a spoilage risk using in-package atmospheric cold plasma.

PubMed

Patange, Apurva; Boehm, Daniela; Bueno-Ferrer, Carmen; Cullen, P J; Bourke, Paula

2017-09-01

Brochothrix thermosphacta is the predominant spoilage microorganism in meat and its control in processing environments is important to maintain meat product quality. Atmospheric cold plasma is of interest for control of pathogenic and spoilage microorganisms in foods. This study ascertained the potential of dielectric barrier discharge atmospheric cold plasma (DBD-ACP) for control of B. thermosphacta, taking microbial and food environment factors into consideration, and investigated the shelf-life of lamb chop after in-package plasma treatment in modified atmosphere. Community profiling was used to assess the treatment effects on the lamb microflora. ACP treatment (80 kV) for 30s inactivated B. thermosphacta populations below detection levels in PBS, while 5 min treatment achieved a 2 Log cycle reduction using a complex meat model medium and attached cells. The antimicrobial efficacy of plasma was reduced but still apparent on lamb chop surface-inoculated with high concentrations of B. thermosphacta. Lamb chop treated under modified atmosphere exhibited reduced microbial growth over the product shelf-life and community profiling showed no evident changes to the microbial populations after the treatment. The overall results indicated potential of ACP to enhance microbial control leading to meat storage life extension through adjusting the modality of treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of chemical sanitizer combined with modified atmosphere packaging on inhibiting Escherichia coli O157:H7 in commercial spinach.

PubMed

Lee, Sun-Young; Baek, Seung-Youb

2008-06-01

Escherichia coli O157:H7 contaminated spinach has recently caused several outbreaks of human illness in the USA and Canada. However, to date, there has been no study demonstrating an effective way to eliminate E. coli O157:H7 in spinach. Therefore, this study was conducted to investigate the effect of chemical sanitizers alone or in combination with packaging methods such as vacuum and modified atmosphere packaging (MAP) on inactivating E. coli O157:H7 in spinach during storage time. Spinach inoculated with E. coli O157:H7 was packaged in four different methods (air, vacuum, N(2) gas, and CO(2) gas packaging) following treatment with water, 100 ppm chlorine dioxide, or 100 ppm sodium hypochlorite for 5 min at room temperature and stored at 7+/-2 degrees C. Treatment with water did not significantly reduce levels of E. coli O157:H7 in spinach. However, treatment with chlorine dioxide and sodium hypochlorite significantly decreased levels of E. coli O157:H7 by 2.6 and 1.1 log(10)CFU/g, respectively. Levels of E. coli O157:H7 in samples packaged in air following treatments grew during storage time, whereas levels were maintained in samples packaged in other packaging methods (vacuum, N(2) gas, and CO(2) gas packaging). Therefore there were significant differences (about 3-4 log) of E. coli O157:H7 populations between samples packed in air and other packaging methods following treatment with chemical sanitizers after 7 days storage. These results suggest that the combination of treatment with chlorine dioxide and packaging methods such as vacuum and MAP may be useful for improving the microbial safety of spinach against E. coli O157:H7 during storage.

Acids in combination with sodium dodecyl sulfate caused quality deterioration of fresh-cut iceberg lettuce during storage in modified atmosphere package.

PubMed

Guan, Wenqiang; Huang, Lihan; Fan, Xuetong

2010-10-01

Recent studies showed that sodium acid sulfate (SAS) and levulinic acid (LA) in combination with sodium dodecyl sulfate (SDS) was effective in inactivating human pathogens on Romaine lettuce. The present study investigated the effects of LA and SAS in combination with SDS (as compared with citric acid and chlorine) on the inactivation of E. coli O157:H7 and sensory quality of fresh-cut Iceberg lettuce in modified atmosphere packages during storage at 4 °C. Results showed that LA (0.5% to 3%) and SAS (0.25% to 0.75%) with 0.05% SDS caused detrimental effects on visual quality and texture of lettuce. LA- and SAS-treated samples were sensorially unacceptable due to development of sogginess and softening after 7 and 14 d storage. It appears that the combined treatments caused an increase in the respiration rate of fresh-cut lettuce as indicated by higher CO(2) and lower O(2) in modified atmosphere packages. On the positive side, the acid treatments inhibited cut edge browning of lettuce pieces developed during storage. LA (0.5%), SAS (0.25%), and citric acid (approximately 0.25%) in combination with SDS reduced population of E. coli OH157:H7 by 0.41, 0.87, and 0.58 log CFU/g, respectively, while chlorine achieved a reduction of 0.94 log CFU/g without damage to the lettuce. Therefore, compared to chlorine, LA and SAS in combination with SDS have limited commercial value for fresh-cut Iceberg lettuce due to quality deterioration during storage.

Characterization of Extracellular Polymeric Substances Produced by Pseudomonas fragi Under Air and Modified Atmosphere Packaging.

PubMed

Wang, Guang-Yu; Ma, Fang; Wang, Hu-Hu; Xu, Xing-Lian; Zhou, Guang-Hong

2017-09-01

Extracellular polymeric substances (EPS) play an important role in bacterial biochemical properties. The characteristics of EPS from 2 strains of Pseudomonas fragi cultured in meat aerobically (control) and in modified atmosphere packaging (MAP) were studied. The amount and components of EPS, the surface properties, and the effect on biofilm formation of several spoilage organisms were evaluated. The results showed that MAP inhibited the growth of the P. fragi strains. Compared with the control, more loose and less bound EPS (containing protein and carbohydrate) were produced by P. fragi in MAP samples. MAP also caused increased cell autoaggregation and surface hydrophobicity. After the removal of the EPS, the surface property changes were strain-dependent, suggesting that membrane compositions were also changed. In addition, the EPS displayed significant antibiofilm activity on Pseudomonas fluorescens and Serratia liquefaciens. In conclusion, P. fragi strains not only modified the amount, components, and surface properties of EPS but also changed the cell membrane compositions to adapt to MAP stress. Moreover, EPS may play an important role in microbial community competitions. © 2017 Institute of Food Technologists®.

Color, lipid oxidation, sensory quality, and aroma compounds of beef steaks displayed under different levels of oxygen in a modified atmosphere package.

PubMed

Resconi, Virginia Celia; Escudero, Ana; Beltrán, José Antonio; Olleta, José Luis; Sañudo, Carlos; Campo, María del Mar

2012-01-01

High oxygen modified atmosphere packaging (MAP) is currently used by the industry to maintain an attractive color in fresh meat. However, it can also promote lipid oxidation and sensory changes. The aim of this study was to compare the quality of beef steaks displayed under different levels of oxygen. For that purpose, meat was stored with 50%, 60%, and 80% of oxygen for 4 and 8 d at retail conditions. A control treatment with steaks vacuum packaged, without exposure to retail display, was included, and color, lipid oxidation, organoleptic characteristics, and aroma compounds were analyzed. Steaks displayed under high oxygen MAP with 50% of oxygen showed the lowest color stability, according to hue values. Higher oxygen levels did not necessarily correspond with higher rancidity levels in the raw meat. Thiobarbituric Acid Reacting Substances (TBARS) values were higher than 2.2 mg malonaldehyde (MDA)/kg muscle in all the samples displayed for 8 d at retail conditions. These samples exhibited the highest intensities of rancid and the least intense beef odors and flavors. The ketones: 2,3-butanedione, 2-octanone, 2,3-pentanedione, 2-heptanone, 4-methyl-2-pentanone, and the aldehydes: pentanal, 2-methyl-butanal, and 2-furfurylthiol, 1-octen-3-ol and 2-methylpropyl-acetate, were proposed as candidates for the aroma differences between the cooked beef steaks stored under vacuum and high oxygen packs. High oxygen modified atmosphere packaging (MAP) is used to increase shelf-life and color at the retail level. However, oxygen deteriorates faster some quality attributes, being a contributor to lipid oxidation that could be perceived at consumption. This study attempts to find the best gas composition in a MAP in order to maintain the color, minimizing the oxidation. Aromatically relevant chemicals have been analyzed by gas olfactometry-gas chromatography as a key to measure beef oxidation after display. © 2011 Institute of Food Technologists®

Testing forward model against OCO-2 and TANSO-FTS/GOSAT observed spectra in near infrared range

NASA Astrophysics Data System (ADS)

Zadvornykh, Ilya V.; Gribanov, Konstantin G.

2015-11-01

An existing software package FIRE-ARMS (Fine InfraRed Explorer for Atmospheric Remote MeasurementS) was modified by embedding vector radiative transfer model VLIDORT. Thus the program tool includes both thermal (TIR) and near infrared (NIR) regions. We performed forward simulation of near infrared spectra on the top of the atmosphere for outgoing radiation accounting multiple scattering in cloudless atmosphere. Simulated spectra are compared with spectra measured by TANSO-FTS/GOSAT and OCO-2 in the condition of cloudless atmosphere over Western Siberia. NCEP/NCAR reanalysis data were used to complete model atmosphere.

Gas Permeability and Permselectivity of Poly(L-Lactic Acid)/SiOx Film and Its Application in Equilibrium-Modified Atmosphere Packaging for Chilled Meat.

PubMed

Dong, Tungalag; Song, Shuxin; Liang, Min; Wang, Yu; Qi, Xiaojing; Zhang, Yuqin; Yun, Xueyan; Jin, Ye

2017-01-01

A layer of SiO x was deposited on the surface of poly(L-lactic acid) (PLLA) film to fabricate a PLLA/SiO x layered film, by plasma-enhanced chemical vapor deposition (PECVD) process. PLLA/SiO x film showed Young's modulus and tensile strength increased by 119.2% and 91.6%, respectively, over those of neat PLLA film. At 5 °C, the oxygen (O 2 ) and carbon dioxide (CO 2 ) permeability of PLLA/SiO x film decreased by 78.7% and 71.7%, respectively, and the CO 2 /O 2 permselectivity increased by 32.5%, compared to that of the neat PLLA film. When the PLLA/SiO x film was applied to the equilibrium-modified atmosphere packaging of chilled meat, the gas composition in packaging reached a dynamic equilibrium with 6% to 11% CO 2 and 8% to 13% O 2 . Combined with tea polyphenol pads, which effectively inhibited the microbial growth, the desirable color of meat was maintained and an extended shelf life of 52 d was achieved for the chilled meat. © 2016 Institute of Food Technologists®.

Selection of the best active modified atmosphere packaging with ethylene and moisture scavengers to maintain quality of guava during low-temperature storage.

PubMed

Murmu, Sanchita Biswas; Mishra, Hari Niwas

2018-07-01

In modified atmosphere packaging of guava, moisture scavenger (MS) sachet containing 30-50 g of coarse silica gel and ethylene scavenger (ES) sachet containing 0-4 g of potassium permanganate was added as per central composite rotatable design. The headspace O 2 and CO 2 of the packages were studied at 4, 8 and 12 °C for 30 days and thereafter the guava were left for two days to ripen at 30 °C. After that the chilling injuries, percentage acceptable guava, peel color and pulp texture was analyzed. After two days ripening at 30 °C the samples with 3 g ES and 46 g MS registered higher L ∗ , lower a ∗ value & firmness (16.65 N), lowest chilling injury score. About 95% of guava was found acceptable in this treatment with 1.89-2.79% reducing sugar, 0.95-1.1% titrable acidity, 59% and 46.61% retention of total phenols and ascorbic acid respectively, resulting 32 days shelf-life of guava. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sensors for Food Safety and Security

NASA Astrophysics Data System (ADS)

Papkovsky, Dmitri B.

Active packaging of food products is aimed at extending shelf life, preserving and improving quality, taste characteristics and appearance of a product. Modified atmosphere packaging (MAP) have become widely used with oxygen sensitive foods, as it enables to inhibit or delay undesirable processes inside packs such as oxidation of lipids and hemecontaining pigments, enzymatic degradation, microbial spoilage, etc. In MAP process, the package container with food is flushed with a mixture of CO2, N2, and O2 gases to replace air, and then sealed. The function of CO2 is to decrease the growth rate of micro-organisms, N2 displaces O2 and also prevents the packaging from collapsing when some of the CO2 is absorbed by moisture in the product1. The majority of MAP foods are packed under the atmosphere with considerably reduced oxygen levels, while products such as raw meat, fruit and vegetables require high concentration of oxygen to keep their appearance and/or shelf life.

Advancements in meat packaging.

PubMed

McMillin, Kenneth W

2017-10-01

Packaging of meat provides the same or similar benefits for raw chilled and processed meats as other types of food packaging. Although air-permeable packaging is most prevalent for raw chilled red meat, vacuum and modified atmosphere packaging offer longer shelf life. The major advancements in meat packaging have been in the widely used plastic polymers while biobased materials and their integration into composite packaging are receiving much attention for functionality and sustainability. At this time, active and intelligent packaging are not widely used for antioxidant, antimicrobial, and other functions to stabilize and enhance meat properties although many options are being developed and investigated. The advances being made in nanotechnology will be incorporated into food packaging and presumably into meat packaging when appropriate and useful. Intelligent packaging using sensors for transmission of desired information and prompting of subsequent changes in packaging materials, environments or the products to maintain safety and quality are still in developmental stages. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nondestructive and continuous monitoring of oxygen levels in modified atmosphere packaged ready-to-eat mixed salad products using optical oxygen sensors, and its effects on sensory and microbiological counts during storage.

PubMed

Hempel, A; O'Sullivan, M G; Papkovsky, D B; Kerry, J P

2013-07-01

The objective of this study was to determine the percentage oxygen consumption of fresh, respiring ready-to-eat (RTE) mixed leaf salad products (Iceberg salad leaf, Caesar salad leaf, and Italian salad leaf). These were held under different modified atmosphere packaging (MAP) conditions (5% O2 , 5% CO2 , 90% N2 (MAPC-commercial control), 21% O2 , 5% CO2 , 74% N2 (MAP 1), 45% O2 , 5% CO2 , 50% N2 (MAP 2), and 60% O2 , 5% CO2 , 35% N2 (MAP 3)) and 4 °C for up to 10 d. The quality and shelf-life stability of all packaged salad products were evaluated using sensory, physiochemical, and microbial assessment. Oxygen levels in all MAP packs were measured on each day of analysis using optical oxygen sensors allowing for nondestructive assessment of packs. Analysis showed that with the exception of control packs, oxygen levels for all MAP treatments decreased by approximately 10% after 7 d of storage. Oxygen levels in control packs were depleted after 7 d of storage. This appears to have had no detrimental effect on either the sensory quality or shelf-life stability of any of the salad products investigated. Additionally, the presence of higher levels of oxygen in modified atmosphere packs did not significantly improve product quality or shelf-life stability; however, these additional levels of oxygen were freely available to fresh respiring produce if required. This study shows that the application of optical sensors in MAP packs was successful in nondestructively monitoring oxygen level, or changes in oxygen level, during refrigerated storage of RTE salad products. © 2013 Institute of Food Technologists®

Effect of Plant Antimicrobial Agents Containing Marinades on Storage Stability and Microbiological Quality of Broiler Chicken Cuts Packed with Modified Atmosphere Packaging.

PubMed

Alakomi, H-L; Maukonen, J; Honkapää, K; Storgårds, E; Quirin, K-W; Yang, B; Saarela, M

2017-10-01

The food industry, including the meat industry, is currently looking for natural preservatives to prevent the growth of harmful microbes in foods. The potential of plant-derived antimicrobial extracts to increase the shelf life and to delay the microbiological spoilage of marinated broiler chicken cuts in modified atmosphere packages during cold storage was investigated in this study. We evaluated the impact of aqueous ethanolic extracts of Finnish sea buckthorn berries and lingonberries and supercritical CO 2 -extracted herbal extracts from an antimicrobial blend and oregano leaves on the shelf life of broiler meat. The commercial antimicrobial blend extract and the oregano extract inhibited the growth of lactic acid bacteria (LAB) and Brochothrix thermosphacta in the marinated samples. The antimicrobial blend extract also reduced the growth of psychrotrophic aerobic bacteria, whereas the sea buckthorn and lingonberry extracts did not. Only minor antimicrobial activity against Enterobacteriaceae by all the extracts was observed. Plate count analysis, denaturing gradient gel electrophoresis, and quantitative real-time PCR indicated that LAB, which are the major spoilage group in marinated modified atmosphere-packaged poultry products, were not significantly affected by the berry extracts studied. During this shelf-life study, LAB isolates of Lactobacillus and Leuconostoc were identified in the marinated samples. Antimicrobial blends and oregano leaf extracts can act as antimicrobial agents in marinade blends, although tailoring of the dose is needed because of their strong taste. Further studies for exploiting synergistic effects of plant extracts could contribute to the development of potential and more effective antimicrobial blends. Studies are needed in meat matrices and in product applications to demonstrate the efficacy of these compounds.

Validation of a predictive model coupling gas transfer and microbial growth in fresh food packed under modified atmosphere.

PubMed

Guillard, V; Couvert, O; Stahl, V; Hanin, A; Denis, C; Huchet, V; Chaix, E; Loriot, C; Vincelot, T; Thuault, D

2016-09-01

Predicting microbial safety of fresh products in modified atmosphere packaging implies to take into account the dynamic of O2, CO2 and N2 exchanges in the system and its effect on microbial growth. In this paper a mechanistic model coupling gas transfer and predictive microbiology was validated using dedicated challenge-tests performed on poultry meat, fresh salmon and processed cheese, inoculated with either Listeria monocytogenes or Pseudomonas fluorescens and packed in commercially used packaging materials (tray + lid films). The model succeeded in predicting the relative variation of O2, CO2 and N2 partial pressure in headspace and the growth of the studied microorganisms without any parameter identification. This work highlighted that the respiration of the targeted microorganism itself and/or that of the naturally present microflora could not be neglected in most of the cases, and could, in the particular case of aerobic microbes contribute to limit the growth by removing all residual O2 in the package. This work also confirmed the low sensitivity of L. monocytogenes toward CO2 while that of P. fluorescens permitted to efficiently prevent its growth by choosing the right combination of packaging gas permeability value and initial % of CO2 initially flushed in the pack. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modified atmosphere packaging of precooked vegetables: effect on physicochemical properties and sensory quality.

PubMed

Barbosa, Carla; Alves, M Rui; Rocha, Susana; Oliveira, M Beatriz P P

2016-03-01

This study aims at verifying the effect of three modified atmosphere packaging (MAP) conditions, all with high CO2 and residual or low O2 contents (%O2/%CO2: 0/40; 2.5/40 and 2.5/60), on the quality preservation of several species of precooked vegetables (cabbage, carrots, green beans and bell peppers). The study was carried out for different storage periods (up to 28 days and 6 sampling periods). Physicochemical parameters (pH, acidity, moisture and ash contents, antioxidant activity, colour, and texture), microbial growth, organoleptic properties and consumer acceptability were assessed. Concerning physicochemical parameters and microbial growth only slight changes without any consistent tendency were observed. This was also confirmed by the trained panel that could not discriminate samples with different storage times. Best preservation conditions were obtained with 0%O2/40%CO2, promoting a shelf life extension of almost 12 days more comparing to commercial conditions presently used. Copyright © 2015 Elsevier Ltd. All rights reserved.

Unravelling proteome changes of chicken egg whites under carbon dioxide modified atmosphere packaging.

PubMed

Xu, Lei; Jia, Fei; Luo, Changyao; Yu, Qianqian; Dai, Ruitong; Li, Xingmin

2018-01-15

Unfertilized chicken eggs within 24h of laying were chosen and stored at 25°C and 45% humidity for 0, 20, and 40days. The experimental group (EG) was the carbon dioxide-modified atmosphere packaging (CDMAP) group, whereas the control group (CG) contained eggs without special handling. Egg freshness indexes were measured. The proteome of the egg whites was determined by LC-MS/MS using isobaric tags for relative and absolute quantitation (iTRAQ). A total of 87 proteins were detected. The results indicated that CDMAP can control the change in protein abundance. Using a correlation analysis between the protein abundance and freshness indexes of the EG, Beta-hexosaminidase, Trypsin inhibitor ClTI-1 and Apolipoprotein D were determined to be potential predictors of egg freshness. In comparing the proteomes of the EG and CG, it was concluded that CDMAP could affect the proteins related to egg vitelline membranes, eggshell matrix and metabolic intensity to maintain egg freshness. Copyright © 2017. Published by Elsevier Ltd.

Integration of antimicrobial pectin-based edible coating and active modified atmosphere packaging to preserve the quality and microbial safety of fresh-cut persimmon (Diospyros kaki Thunb. cv. Rojo Brillante).

PubMed

Sanchís, Elena; Ghidelli, Christian; Sheth, Chirag C; Mateos, Milagros; Palou, Lluís; Pérez-Gago, María B

2017-01-01

The greatest hurdle to the commercial marketing of fresh-cut fruits is related to their higher susceptibility to enzymatic browning, tissue softening, and microbial growth. The aim of this study was to test the efficacy of a pectin-based edible coating and low oxygen modified atmosphere packaging (MAP) to control enzymatic browning and reduce microbial growth of fresh-cut 'Rojo Brillante' persimmon. The survival of Escherichia coli, Salmonella enteritidis and Listeria monocytogenes artificially inoculated on fresh-cut fruit was also assessed. The pectin coating was amended with 500 IU mL -1 nisin (NI) as antimicrobial agent and 10 g kg -1 citric acid and 10 g kg -1 calcium chloride as anti-browning and firming agents, respectively. Persimmon slices were dipped in the coating or in water (control) and packed under 5 kPa O 2 (MAP) or in ambient atmosphere for up to 9 days at 5 °C. Microbial growth, package gas composition, colour, firmness, polyphenol oxidase activity, visual quality and overall sensory flavour of persimmon slices were measured during storage. Coating application combined with active MAP significantly reduced the CO 2 emission and O 2 consumption in the package. The coating was effective in reducing browning and also inhibited the growth of mesophilic aerobic bacteria. Coating also reduced the populations of E. coli, S. enteritidis and L. monocytogenes. The combination of the pectin-based edible coating and active MAP proved to be the most effective treatment to maintain the sensory and microbiological quality of persimmon slices for more than 9 days of storage. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Effect of modified atmosphere packaging on the persistence and expression of virulence factors of Escherichia coli O157:H7 on shredded iceberg lettuce.

PubMed

Sharma, Manan; Lakshman, Sudesna; Ferguson, Sean; Ingram, David T; Luo, Yaguang; Patel, Jitu

2011-05-01

Fresh-cut leafy greens contaminated with Escherichia coli O157:H7 have caused foodborne outbreaks. Packaging conditions, coupled with abusive storage temperatures of contaminated lettuce, were evaluated for their effect on the potential virulence of E. coli O157:H7. Shredded lettuce was inoculated with 5.58 and 3.98 log CFU E. coli O157:H7 per g and stored at 4 and 15°C, respectively, for up to 10 days. Lettuce was packaged under treatment A (modified atmosphere packaging conditions used for commercial fresh-cut produce, in gas-permeable film with N(2)), treatment B (near-ambient air atmospheric conditions in a gas-permeable film with microperforations), and treatment C (high-CO(2) and low-O(2) conditions in a gas-impermeable film). E. coli O157:H7 populations from each treatment were determined by enumeration of numbers on MacConkey agar containing nalidixic acid. RNA was extracted from packaged lettuce for analysis of expression of virulence factor genes stx(2), eae, ehxA, iha, and rfbE. E. coli O157:H7 populations on lettuce at 4°C under all treatments decreased, but most considerably so under treatment B over 10 days. At 15°C, E. coli O157:H7 populations increased by at least 2.76 log CFU/g under all treatments. At 15°C, expression of eae and iha was significantly greater under treatment B than it was under treatments A and C on day 3. Similarly, treatment B promoted significantly higher expression of stx(2), eae, ehxA, and rfbE genes on day 10, compared with treatments A and C at 15°C. Results indicate that storage under near-ambient air atmospheric conditions can promote higher expression levels of O157 virulence factors on lettuce, and could affect the severity of E. coli O157:H7 infections associated with leafy greens.

Inhibition of Escherichia coli O157:H7 and Clostridium sporogenes in spinach packaged in modified atmospheres after treatment combined with chlorine and lactic acid bacteria.

PubMed

Brown, Alison L; Brooks, J Chance; Karunasena, Enusha; Echeverry, Alejandro; Laury, Angela; Brashears, Mindy M

2011-08-01

Implementation of modified atmospheric packaging (MAP) into retail produce is a less commonly practiced method due to differences among commodities and the potential growth of anaerobes. Pathogens including Escherichia coli O157:H7 have been responsible for spinach outbreaks across the United States. In this study, hurdles, including those currently used with produce safety, such as MAP and chlorine, were combined with lactic acid bacteria (LAB) to inhibit pathogens. Spinach was coinoculated with E. coli O157:H7 and Clostridium sporogenes, a surrogate for C. botulinum, and treated with water or a hurdle that included water, chlorine, and LAB. Spinach from treatments were packaged in air (traditional), oxygen (80% O₂, 20% CO₂), or nitrogen (80% N₂, 20% CO₂) and stored in a retail display case for 9 d at 4 to 7 °C. The hurdle inhibited E. coli O157:H7 and C. sporogenes compared to controls with reductions of 1.43 and 1.10 log (P < 0.05), respectively. The nitrogen atmosphere was outperformed by air and oxygen in the reduction of E. coli O157:H7 (P < 0.05) with a decrease of 0.26 and 0.15 logs. There were no significant differences among the 3 atmospheres on C. sporogenes survival. Relative to these hurdles, we also chose to evaluate the potential benefits of LAB in pathogen control. The survival of LAB in interventions demonstrates implementation of LAB into produce could control pathogens, without damaging produce or altering organoleptic properties. The goal of our work was to identify methods that could reduce food-borne pathogens in packaged spinach products. Using current industry techniques in combination with unique methods, such as the use of beneficial bacteria, our research identified whether harmful microorganisms could be eliminated. Our data demonstrate that specific packaging conditions with beneficial bacteria can help eliminate or reduce the survival of E. coli O157:H7 and C. sporogenes (a model for C. botulinum) in produce. Journal of Food Science © 2011 Institute of Food Technologists® No claim to original US government works.

Effect of modified atmosphere packaging on the shelf life of sliced wheat flour bread.

PubMed

Rodríguez, M; Medina, L M; Jordano, R

2000-08-01

The application of modified atmospheres packaging (MAP) of sliced bread with different aw, moisture content and pH values, with or without preservative added (calcium propionate) and at different storage temperatures, has been studied with the aim of establishing the effect of MAP on the shelf-life of the selected product. Four atmospheres were tested per batch: 100% N2, 20% CO2/80% N2, 50% CO2/50% N2 and a standard air control. In samples without added preservative in CO2:N2 (50:50), the increases in shelf life were 117% and 158% at 22-25 degrees C and 15-20 degrees C, respectively. In samples with added preservative in 100% N2, shelf life was increased by 116%. Samples with added preservative in 20% CO2:80% N2 increased shelf life by 150% and 131% at 22-25 degrees C and 15-20 degrees C, respectively. By increasing the CO2 concentration to 50%, the increases in shelf life of the samples with added preservative were 167% and 195% at 22-25 degrees C and 15-20 degrees C, respectively.

Effect of Initial Headspace O2 Level on the Growth and Volatile Metabolite Production of Leuconostoc Mesenteriodes and the Microbial and Sensorial Quality of Modified Atmosphere Packaged Par-Fried French Fries.

PubMed

Samapundo, Simbarashe; Mujuru, Felix Mugove; de Baenst, Ilse; Denon, Quenten; Devlieghere, Frank

2016-02-01

This study evaluated the effect of residual O2 level (0% to 5%) on microbial growth and volatile metabolite production on par-fried French fries packaged in a modified atmosphere with 60% CO2 (rest N2 ) at 4 °C. The results obtained showed that the initial headspace (IH) O2 level had an effect on growth of Leuconostoc mesenteroides on French fry simulation agar, whereby growth was slightly faster under 5% O2 . In terms of quantity, ethanol, 2-methyl-1-propanol, and dimethyl disulphide were the most significant volatile metabolites produced by L. mesenteroides. The production of ethanol by L. mesenteroides was highest on simulation agar packaged under low IH O2 levels (0% to 1%), indicating that the fermentative metabolism was induced under these conditions. In agreement with the results observed on the simulation medium, growth of native lactic acid bacteria was faster under an IH O2 level of 5%. In addition, ethanol, 2-methyl-1-propanol, and dimethyl disulphide were also quantitatively the most important volatile metabolites. However, in contrast, greater quantities of ethanol and dimethyl disulphide were produced on par-fried French fries packaged under 5% O2 . This was attributed to the limited growth of the native flora on the par-fried French fries under residual O2 levels of 0% and 1%. Although some significant differences (P < 0.05) occurred between the French fries packaged in 0%, 1%, and 5 % residual O2 during storage, all products were considered to be acceptable for consumption. The results of this study can be used to optimize the shelf-life of packaged chill stored potato products. © 2016 Institute of Food Technologists®

Effect of modified atmosphere packaging on Quality Index Method (QIM) scores of farmed gilthead seabream (Sparus aurata L.) at low and abused temperatures.

PubMed

Campus, Marco; Bonaglini, Elia; Cappuccinelli, Roberto; Porcu, Maria Cristina; Tonelli, Roberto; Roggio, Tonina

2011-04-01

A Quality Index Method (QIM) scheme was developed for modified atmosphere packaging (MAP) packed gilthead seabream, and the effect of MAP gas mixtures (60% CO2 and 40% N2; 60% CO2, 30% O2, and 10% N2), temperature (2, 4, and 8 °C), and time of storage on QI scores was assessed. QI scores were crossed with sensory evaluation of cooked fish according to a modified Torry scheme to establish the rejection point. In order to reduce redundant parameters, a principal component analysis was applied on preliminary QIM parameters scores coming from the best performing MAP among those tested. The final QIM scheme consists of 13 parameters and a maximum demerit score of 25. The maximum storage time was found to be 13 d at 4 °C for MAP 60% CO2 and 40% N2. Storage at 2 °C do not substantially improved sensory parameters scores, while storage under temperature abuse (8 °C) accelerated drastically the rate of increase of QI scores and reduced the maximum storage time to 6 d.

The prevalence and some metabolic traits of Brochothrix thermosphacta in meat and meat products packaged in different ways.

PubMed

Nowak, Agnieszka; Rygala, Anna; Oltuszak-Walczak, Elzbieta; Walczak, Piotr

2012-04-01

The effect of Brochothrix thermosphacta on the quality of meat and meat products is of vital importance in connection with Regulation EC/178/2002 extending the definition of unsafe foodstuffs to encompass all those which are unfit for human consumption. This study aimed to determine the prevalence of B. thermosphacta in meat and meat products packaged under different conditions and to estimate the effect of B. thermosphacta strains on product quality based on their protein and lipid degradation activity. B. thermosphacta was absent in only two of 132 samples. All other samples were contaminated with this bacterium (10(1) to 10(9) cfu g(-1) meat and 10(2) to 10(8) cfu g(-1) meat product). In products stored under high-oxygen atmosphere Brochothrix cells accounted for almost 100% total mesophilic count (TMC) and below 50% TMC in oxygen-free atmosphere. While the tested B. thermosphacta strains did not show any proteolytic activity, most of them displayed lipolytic activity at 25 °C and some even at 4 °C. B. thermosphacta is commonly present in meat and meat products packaged in different ways. This bacterium can display lipolytic activity also at refrigeration temperature. Its over-proliferation can be inhibited through vacuum packaging or packaging under a modified atmosphere with reduced oxygen content. Copyright © 2011 Society of Chemical Industry.

Antioxidant Extracts from Acorns (Quercus ilex L.) Effectively Protect Ready-to-Eat (RTE) Chicken Patties Irrespective of Packaging Atmosphere.

PubMed

Ferreira, Valquíria C S; Morcuende, David; Hérnandez-López, Silvia H; Madruga, Marta S; Silva, Fábio A P; Estévez, Mario

2017-03-01

This study evaluated the impact of a phenolic-rich acorn extract (200 ppm gallic acid equivalents) and the concentration of oxygen in the packaging system (low-oxygen modified atmosphere; 5% vs. normal-oxygen; 21%) on lipid and protein oxidation and consumers acceptance of the ready-to-eat chicken patties. Samples were subjected to cooking (electric oven, 170 °C/16 min), cold storage (14 d at 4 °C), and reheating (microwave, 600 mW/1 min). Samples treated with acorn extract kept thiobarbituric acid-reactive substances numbers and lipid-derived volatiles at basal levels throughout the whole processing irrespective of the oxygen concentration in the packaging atmosphere. Consistently, treated patties had lower protein carbonyls than control ones. The acorn extract also controlled color and texture deterioration during chilled storage and reheating and improved the color and odor acceptance of the products. Formulating with acorn extract is a feasible strategy to inhibit the oxidation-driven changes and preserve the quality of reheated samples as if there were freshly cooked. Compared to the effect of the antioxidant extract, the concentration of oxygen in the packaging system was negligible in terms of quality preservation. © 2017 Institute of Food Technologists®.

Effects of Low-Oxygen Environments on the radiation tolerance of the cabbage looper moth (Lepidoptera: noctuidae)

USDA-ARS?s Scientific Manuscript database

Ionizing radiation is phytosanitary treatment to mitigate risks associated with trade of fresh fruits and vegetables. Commodity producers wish to irradiate fresh product stored in modified atmosphere packaging that increases shelf life and delays ripening. However, irradiating insects in anoxia incr...

Accuracy, reliability, and timing of visual evaluations of decay in fresh-cut lettuce

USDA-ARS?s Scientific Manuscript database

Visual assessments are used for evaluating the quality of food products, such as fresh-cut lettuce packaged in bags with modified atmosphere. We have compared the accuracy and the reliability of visual evaluations of decay on fresh-cut lettuce performed with experienced and inexperienced raters. In ...

Modeling the Effect of Modified Atmospheres on Conidial Germination of Fungi from Dairy Foods

PubMed Central

Nguyen Van Long, Nicolas; Vasseur, Valérie; Couvert, Olivier; Coroller, Louis; Burlot, Marion; Rigalma, Karim; Mounier, Jérôme

2017-01-01

Modified atmosphere packaging (MAP) is commonly applied to extend food shelf-life. Despite growth of a wide variety of fungal contaminants has been previously studied in relation to modified-atmospheres, few studies aimed at quantifying the effects of dioxygen (O2) and carbon dioxide (CO2) partial pressures on conidial germination in solid agar medium. In the present study, an original culture method was developed, allowing microscopic monitoring of conidial germination under modified-atmospheres in static conditions. An asymmetric model was utilized to describe germination kinetics of Paecilomyces niveus, Mucor lanceolatus, Penicillium brevicompactum, Penicillium expansum, and Penicillium roquefoti, using two main parameters, i.e., median germination time (τ) and maximum germination percentage (Pmax). These two parameters were subsequently modeled as a function of O2 partial pressure ranging from 0 to 21% and CO2 partial pressure ranging from 0.03 to 70% (8 tested levels for both O2 and CO2). Modified atmospheres with residual O2 or CO2 partial pressures below 1% and up to 70%, respectively, were not sufficient to totally inhibit conidial germination,. However, O2 levels < 1% or CO2 levels > 20% significantly increased τ and/or reduced Pmax, depending on the fungal species. Overall, the present method and results are of interest for predictive mycology applied to fungal spoilage of MAP food products. PMID:29163403

Extending the shelf life of kohlrabi stems by modified atmosphere packaging.

PubMed

Escalona, V H; Aguayo, E; Artés, F

2007-06-01

Kohlrabi stems (without leaves) were stored under modified atmosphere packaging (MAP) for 60 d at 0 degrees C. An additional retail sale period of 3 d at 12 degrees C after each cold storage evaluation (30 and 60 d) was applied. Under high relative humidity (RH) and 0 degrees C, the stems showed low metabolic activity, as no changes in sugars and organic acids were found. From day 21 at 0 degrees C, air-stored stems showed a yellowing of stalks and later they fell down. This disorder severely affected the appearance of stems. A gas composition of 4.5 to 5.5 kPa O(2) plus 11 to 12 kPa CO(2) was reached using antimist oriented polypropylene plastic bags of 20-mum thicknesses. The stems in MAP conditions kept a high sensorial quality. It was enough for commercial purpose of 2 mo. The storage of kohlrabi stems in plastic bags, either MA or in perforated (control) packages, provided an additional protection reducing physical damage. The MAP conditions delayed the weight loss and development of bacterial soft and black rot, extending the shelf life of kohlrabi stems to 60 d at 0 degrees C plus 3 d at 12 degrees C. Stems are not chilling injury sensitive.

Phenol metabolism and preservation of fresh in-hull walnut stored in modified atmosphere packaging.

PubMed

Wang, Jin; Li, Pan; Gong, Bi; Li, Shuying; Ma, Huiling

2017-12-01

The effects of modified atmosphere packaging (MAP) on phenol metabolism and preservation of fresh in-hull walnuts have been investigated. Fruit was packaged under MAP1 (film thickness, 30 μm), MAP2 (45 μm) and MAP3 (50 μm) and stored at -0.5 to 1.0 °C for up to 60 days. Firmness, soluble solid concentration, total phenols, total flavonoids and total antioxidant activity of the green hull were maintained at higher levels under the MAP conditions, whereas decay incidence was lower compared to the control during storage. Green hull of fruit under MAP conditions contained lower polyphenol oxidase activity than the control and the peroxidase activity was at a similar level to the control after 18 days. Phenylalanine ammonialyase activity was enhanced by MAP conditions, with two peaks on days 18 and 36. Until day 60, the peroxide value and acid value of kernel oils under MAP conditions were lower than that of the control. The MAP3 treatment was most effective for maintaining kernel quality. The protective role of MAP conditions on phenolic contents in green hull may contribute to the mitigation of decay and the maintenance of kernel quality. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Effect of high carbon dioxide atmosphere packaging and soluble gas stabilization pre-treatment on the shelf-life and quality of chicken drumsticks.

PubMed

Al-Nehlawi, A; Saldo, J; Vega, L F; Guri, S

2013-05-01

The effects of an aerobic modified atmosphere packaging (MAP) (70% CO2, 15% O2 and 15% N2) with and without a CO2 3-h soluble gas stabilization (SGS) pre-treatment of chicken drumsticks were determined for various package and product quality characteristics. The CO2 dissolved into drumsticks was determined. The equilibrium between CO2 dissolved in drumsticks and CO2 in head space was reached within 48h after packaging, showing highest values of CO2 in SGS pre-treated samples. This greater availability of CO2 resulted in lower counts of TAB and Pseudomonas in SGS than in MAP drumsticks. Package collapse was significantly reduced in SGS samples. The average of CO2 dissolved in the MAP treatment was 567mg CO2kg(-1) of chicken and, 361mg CO2kg(-1) of chicken during the MAP treatment, in SGS pre-treated samples. This difference could be the quantity of CO2 dissolved during SGS pre-treatment. These results highlight the advantages of using SGS versus traditional MAP for chicken products preservation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Carbon monoxide measurement in the global atmospheric sampling program

NASA Technical Reports Server (NTRS)

Dudzinski, T. J.

1979-01-01

The carbon monoxide measurement system used in the NASA Global Atmospheric Sampling Program (GASP) is described. The system used a modified version of a commercially available infrared absorption analyzer. The modifications increased the sensitivity of the analyzer to 1 ppmv full scale, with a limit of detectability of 0.02 ppmv. Packaging was modified for automatic, unattended operation in an aircraft environment. The GASP system is described along with analyzer operation, calibration procedures, and measurement errors. Uncertainty of the CO measurement over a 2-year period ranged from + or - 3 to + or - 13 percent of reading, plus an error due to random fluctuation of the output signal + or - 3 to + or - 15 ppbv.

Lipid degradation and sensory characteristics of ripened sausages packed in modified atmosphere at different carbon dioxide concentrations.

PubMed

Summo, Carmine; Pasqualone, Antonella; Paradiso, Vito Michele; Centomani, Isabella; Centoducati, Gerardo; Caponio, Francesco

2016-01-15

Conflicting results about the effect of modified atmosphere packaging (MAP) rich in CO2 on the quality of different kinds of meat products are present in the literature. In this study, the degree of lipid degradation and the sensory characteristics of ripened sausages packed in modified atmosphere at three different carbon dioxide (CO2) concentrations were evaluated during 5 months of storage. The degree of hydrolytic degradation of the lipid fraction was found to decrease with increasing CO2 concentration. Similarly, oxidative phenomena occurred at a lower rate when the CO2 concentration increased. The variations in CO2 concentration influenced the perception of rancid flavor in the examined sausages. An increase in CO2 concentration in MAP slowed down the evolution of lipid oxidation owing to the minor extent of hydrolytic degradation, whose products have pro-oxidant activity. This effect was more evident in the first 2 months of storage. © 2015 Society of Chemical Industry.

Correlation between microbial flora, sensory changes and biogenic amines formation in fresh chicken meat stored aerobically or under modified atmosphere packaging at 4 degrees C: possible role of biogenic amines as spoilage indicators.

PubMed

Balamatsia, C C; Paleologos, E K; Kontominas, M G; Savvaidis, I N

2006-01-01

This study evaluated the formation of biogenic amines (BAs) in breast chicken meat during storage under aerobic and modified atmospheric packaging (MAP) conditions at 4 degrees C, the correlation of microbial and sensory changes in chicken meat with formation of BAs and the possible role of BAs as indicators of poultry meat spoilage. Poultry breast fillets were stored aerobically or under MAP (30%, CO(2), 70% N(2)) at 4 degrees C for up to 17 days. Quality evaluation was carried out using microbiological, chemical and sensory analyses. Total viable counts, Pseudomonads and Enterobacteriaceae, were in general higher for chicken samples packaged in air whereas lactic acid bacteria (LAB) and Enterobacteriaceae were among the dominant species for samples under MAP. Levels of putrescine and cadaverine increased linearly with storage time and were higher in aerobically stored chicken samples. Spermine and spermidine levels were also detected in both aerobically and MAP stored chicken meat. Levels of tyramine in both chicken samples stored aerobically and or under MAP were low (< 10 mg kg(-1)) whereas the formation of histamine was only observed after day 11 of storage when Enterobacteriaceae had reached a population of ca. 10(7) CFU g(-1). Based on sensory and microbiological analyses and also taking into account a biogenic amines index (BAI, sum of putrescine, cadaverine and tyramine), BAI values between 96 and 101 mg kg(-1) may be proposed as a quality index of MAP and aerobically-packaged fresh chicken meat. Spermine and spermidine decreased steadily throughout the entire storage period of chicken meat under aerobic and MAP packaging, and thus these two amines cannot be used as indicators of fresh chicken meat quality.

Shuttle derived atmospheric density model. Part 1: Comparisons of the various ambient atmospheric source data with derived parameters from the first twelve STS entry flights, a data package for AOTV atmospheric development

NASA Technical Reports Server (NTRS)

Findlay, J. T.; Kelly, G. M.; Troutman, P. A.

1984-01-01

The ambient atmospheric parameter comparisons versus derived values from the first twelve Space Shuttle Orbiter entry flights are presented. Available flights, flight data products, and data sources utilized are reviewed. Comparisons are presented based on remote meteorological measurements as well as two comprehensive models which incorporate latitudinal and seasonal effects. These are the Air Force 1978 Reference Atmosphere and the Marshall Space Flight Center Global Reference Model (GRAM). Atmospheric structure sensible in the Shuttle flight data is shown and discussed. A model for consideration in Aero-assisted Orbital Transfer Vehicle (AOTV) trajectory analysis, proposed to modify the GRAM data to emulate Shuttle experiments.

Application of chlorophyll fluorescence imaging and hyperspectral imaging in evaluation of decay in fresh-cut lettuce

USDA-ARS?s Scientific Manuscript database

Lettuce (Lactuca sativa L.) is commercially the most popular leafy vegetable whose leaves are usually consumed raw. Cleaned, cored, and chopped (fresh-cut) lettuce is a desirable, but highly perishable product. Modified atmosphere packaging (MAP) has been introduced to maintain quality of fresh-cut ...

Detection of decay in fresh-cut lettuce using hyperspectral imaging and chlorophyll fluorescence imaging

USDA-ARS?s Scientific Manuscript database

Fresh-cut lettuce sold in modified atmosphere packaging (MAP) is a desirable, but highly perishable product. Decay of tissue can start a few days after processing and may be difficult to detect by quick visual observation. A system for early detection of decay and gradual evaluation of its progress ...

Effect of light exposure on sensorial quality, concentrations of bioactive compounds and antioxidant capacity of radish microgreens during low temperature storage

USDA-ARS?s Scientific Manuscript database

Daikon radish microgreens constitute a good source of bioactive compounds. However, the quality deteriorates rapidly during postharvest storage. In this study, we investigated the effects of light exposure and modified atmosphere packaging conditions on changes in sensorial quality and retention of ...

Effect of rosemary essential oil and modified-atmosphere packaging (MAP) on meat quality and survival of pathogens in poultry fillets

PubMed Central

Kahraman, Tolga; Issa, Ghassan; Bingol, Enver Baris; Kahraman, Beren Basaran; Dumen, Emek

2015-01-01

The effect of rosemary (Rosmarinus officinalis L.) essential oil (REO) and modified-atmosphere packaging (MAP) on the survival of certain pathogens (Salmonella Typhimurium and Listeria monocytogenes) in poultry fillets and on their meat quality during 7 days of refrigerated storage were investigated. Because REO at 0.05% and 0.1% had weak antibacterial activity and REO at 0.3%, 0.5% and 1.0% imparted unacceptable organoleptic properties, only REO at 0.2% was used to treat the poultry meat. The results showed that adding 0.2% REO to poultry fillets did not reduce the size of the population of S. Typhimurium and L. monocytogenes. However, REO treatment significantly decreased the L* (lightness) value and increased the a* (redness) value of stored fillets, and adding REO in combination with MAP reduced the level of lipid oxidation. In conclusion, in a suitable combination, REO can be applied to improve the quality of meat, but further studies should be conducted to determine the appropriate commercial level for different meat products. PMID:26273279

Effect of modified atmospheric packaging on the shelf stability of paneer prepared by adopting hurdle technology.

PubMed

Thippeswamy, L; Venkateshaiah, B V; Patil, Sharanagouda B

2011-04-01

Paneer was prepared by application of hurdle technology (HT) and its shelf stability studied by modified atmospheric packaging (MAP). The hurdles adopted comprised of water activity (aw), pH, preservative and MAP. The aw was reduced by using NaCl (1-3%), citric acid (CA, 0.01-0.1%) and potassium sorbate (0.1%). NaCl and CA at 3 and 0.1% reduced aw from 0.994 to 0.970 and pH from 5.6 to 5.1, respectively. Sensory scores of all samples decreased (p ≤ 0.05) from control during storage at different temperatures, but these scores at the end of 20 days were still under acceptable limit of 6 and above (liked moderately). MAP was carried out by using a mixture of CO2 to N2 in the ratio of 50:50. The HT adopted paneer with MAP had extended the shelf-life from 1 to 12 days at room temperature (30 ± 1°C) and 6 to 20 days at refrigeration (7 ± 1°C) temperatures.

Effect of gallic acid/chitosan coating on fresh pork quality in modified atmosphere packaging.

PubMed

Fang, Zhongxiang; Lin, Daniel; Warner, Robyn Dorothy; Ha, Minh

2018-09-15

Fresh meat safety and quality is a major concern of consumers in the current food market. The objective of this research was to investigate a newly developed gallic acid/chitosan edible coating on the preservation of fresh pork quality in modified atmosphere package (MAP) stored at 4 °C. The pork loins were coated with 2% chitosan (CHI), 0.2% gallic acid in 2% chitosan (CHI/0.2G), or 0.4% gallic acid in 2% chitosan (CHI/0.4G). Results showed that the antimicrobial activity of the chitosan coating was increased with the incorporation of gallic acid. The CHI/0.2G and CHI/0.4G pork loins also had lower lipid oxidation and myoglobin oxidation. However, the CHI/0.4G sample exhibited a pro-protein oxidation effect, suggesting an optimal concentration of gallic acid should be incorporated. This research provides a practical method in application of gallic acid/chitosan coatings on preservation of fresh pork to improve the safety and quality in MAP environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Current topics in active and intelligent food packaging for preservation of fresh foods.

PubMed

Lee, Seung Yuan; Lee, Seung Jae; Choi, Dong Soo; Hur, Sun Jin

2015-11-01

The purpose of this review is to provide an overview of current packaging systems, e.g. active packaging and intelligent packaging, for various foods. Active packaging, such as modified atmosphere packaging (MAP), extends the shelf life of fresh produce, provides a high-quality product, reduces economic losses, including those caused by delay of ripening, and improves appearance. However, in active packaging, several variables must be considered, such as temperature control and different gas formulations with different product types and microorganisms. Active packaging refers to the incorporation of additive agents into packaging materials with the purpose of maintaining or extending food product quality and shelf life. Intelligent packaging is emerging as a potential advantage in food processing and is an especially useful tool for tracking product information and monitoring product conditions. Moreover, intelligent packaging facilitates data access and information exchange by altering conditions inside or outside the packaging and product. In spite of these advantages, few of these packaging systems are commercialized because of high cost, strict safety and hygiene regulations or limited consumer acceptance. Therefore more research is needed to develop cheaper, more easily applicable and effective packaging systems for various foods. © 2015 Society of Chemical Industry.

Smart Packaging Technologies and Their Application in Conventional Meat Packaging Systems

NASA Astrophysics Data System (ADS)

O'Grady, Michael N.; Kerry, Joseph P.

Preservative packaging of meat and meat products should maintain acceptable appearance, odour and flavour and should delay the onset of microbial spoilage. Typically fresh red meats are placed on trays and over-wrapped with an oxygen permeable film or alternatively, meats are stored in modified atmosphere packages (MAP) containing high levels of oxygen and carbon dioxide (80% O2:20% CO2) (Georgala & Davidson, 1970). Cooked meats are usually stored in 70% N2:30% CO2 (Smiddy, Papkovsky, & Kerry, 2002). The function of oxygen in MAP is to maintain acceptable fresh meat colour and carbon dioxide inhibits the growth of spoilage bacteria (Seideman & Durland, 1984). Nitrogen is used as an inert filler gas either to reduce the proportions of the other gases or to maintain the pack shape (Bell & Bourke, 1996).

Feasibility of biodegradable based packaging used for red meat storage during shelf-life: A pilot study.

PubMed

Panseri, S; Martino, P A; Cagnardi, P; Celano, G; Tedesco, D; Castrica, M; Balzaretti, C; Chiesa, L M

2018-05-30

This study was designated to ascertain the effectiveness of polylactic acid (PLA) based packaging solution to store red fresh meat during its refrigerated shelf-life. Recently the attention in the packaging industry regarding the use of bioplastics has been shifting from compostable/biodegradable materials toward biobased materials. Steaks obtained from semimembranous muscle of Piemontese beef were packaged in PLA trays closed with a lid made of PLA film and for comparison purposed in a conventional reference package consisting of a amorphous polyethylene terephthalate/polyethylene (APET/PET) trays and wrapped in plastic film of polyvinyl chloride (PVC). The packaging under modified atmosphere MAP was carried out by using a gas mixture of 66% O 2 , 25% CO 2 and 9%N 2 . By using PLA packaging combination it was possible to maintain an optimum red colour together with a reduced content of volatile compounds associated to off-flavours of meat samples particularly related to the oxidation phenomena. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of different packaging methods and storage temperature on microbiological and physicochemical quality characteristics of meatball.

PubMed

Yilmaz, I; Demirci, M

2010-06-01

The objective of this research was to determine physicochemical changes and microbiological quality of the different packaged meatball samples. Meatball samples in polystyrene tray were closed with polyethylene film (PS packs), vacuumed and modified atmosphere packaged, (MAP) (65% N(2), 35% CO(2)), and held under refrigerated display (4 °C) for 8, 16 and 16 days for PS packs, vacuum and MAP, respectively. Microbial load, free fatty acids and thiobarbituric acid values of the samples tended to increase with storage time. Bacteria counts of the raw meatball samples increased 2 log cycles at the end of storage compared with initial values. Meatball samples can be stored without any microbiological problem for 7 days at 4 °C. Results from this study suggested that shelf-life assigned to modified-MAP and vacuum-packed meatballs may be appropriate. Meatball samples underwent physical deformation when they were packed before vacuum process. With these negative factors considered, MAP is superior to other two packs methods.

Minimal processing of iceberg lettuce has no substantial influence on the survival, attachment and internalization of E. coli O157 and Salmonella.

PubMed

Van der Linden, Inge; Avalos Llano, Karina R; Eriksson, Markus; De Vos, Winnok H; Van Damme, Els J M; Uyttendaele, Mieke; Devlieghere, Frank

2016-12-05

The influence of a selection of minimal processing techniques (sanitizing wash prior to packaging, modified atmosphere, storage conditions under light or in the dark) was investigated in relation to the survival of, attachment to and internalization of enteric pathogens in fresh produce. Cut Iceberg lettuce was chosen as a model for fresh produce, Escherichia coli O157:H7 (E. coli O157) and Salmonella enterica were chosen as pathogen models. Care was taken to simulate industrial post-harvest processing. A total of 50±0.1g of fresh-cut Iceberg lettuce was packed in bags under near ambient atmospheric air with approximately 21% O 2 (NAA) conditions or equilibrium modified atmosphere with 3% O 2 (EMAP). Two lettuce pieces inoculated with E. coli O157 BRMSID 188 or Salmonella Typhimurium labeled with green fluorescent protein (GFP) were added to each package. The bags with cut lettuce were stored under either dark or light conditions for 2days at 7°C. The pathogens' capacity to attach to the lettuce surface and cut edge was evaluated 2days after inoculation using conventional plating technique and the internalization of the bacteria was investigated and quantified using confocal microscopy. The effect of a sanitizing wash step (40mg/L NaClO or 40mg/L peracetic acid+1143mg/L lactic acid) of the cut lettuce prior to packaging was evaluated as well. Our results indicate that both pathogens behaved similarly under the investigated conditions. Pathogen growth was not observed, nor was there any substantial influence of the investigated atmospheric conditions or light/dark storage conditions on their attachment/internalization. The pathogens attached to and internalized via cut edges and wounds, from which they were able to penetrate into the parenchyma. Internalization through the stomata into the parenchyma was not observed, although some bacteria were found in the substomatal cavity. Washing the cut edges with sanitizing agents to reduce enteric pathogen numbers was not more effective than a rinse with precooled tap water prior to packaging. Our results confirm that cut surfaces are the main risk for postharvest attachment and internalization of E. coli O157 and Salmonella during minimal processing and that storage and packaging conditions have no important effect. Copyright © 2016 Elsevier B.V. All rights reserved.

Consumer preferences for beef color and packaging did not affect eating satisfaction.

PubMed

Carpenter, C E; Cornforth, D P; Whittier, D

2001-04-01

We investigated whether consumer preferences for beef colors (red, purple, and brown) or for beef packaging systems (modified atmosphere, MAP; vacuum skin pack, VSP; or overwrap with polyvinyl chloride, PVC) influenced taste scores of beef steaks and patties. To test beef color effects, boneless beef top loin steaks (choice) and ground beef patties (20% fat) were packaged in different atmospheres to promote development of red, purple, and brown color. To test effects of package type, steaks and patties were pre-treated with carbon monoxide in MAP to promote development of red color, and some meat was repackaged using VSP or PVC overwrap. The differently colored and packaged meats were separately displayed for members of four consumer panels who evaluated appearance and indicated their likelihood to purchase similar meat. Next, the panelists tasted meat samples from what they had been told were the packaging treatments just observed. However, the meat samples actually served were from a single untreated steak or patty. Thus, any difference in taste scores should reflect expectations established during the visual evaluation. The same ballot and sample coding were used for both the visual and taste evaluations. Color and packaging influenced (P<0.001) appearance scores and likelihood to purchase. Appearance scores were rated red>purple >brown and PVC >VSP>MAP. Appearance scores and likelihood to purchase were correlated (r=0.9). However, color or packaging did not affect (P>0.5) taste scores. Thus, consumer preferences for beef color and packaging influenced likelihood to purchase, but did not bias eating satisfaction.

Effect of different gas stunning methods on Manchega suckling lamb meat packed under different modified atmospheres.

PubMed

Bórnez, R; Linares, M B; Vergara, H

2010-04-01

Forty-nine Manchega breed male suckling lambs were used in this experiment. The effect of CO(2) concentration and exposure time at stunning [80% CO(2) for 90 s (G1); 90% CO(2) for 90 s (G2); 90% CO(2) for 60 s (G3); 80% CO(2) for 60 s (G4)] plus an electrically stunned control group (G5) was assessed for pH, colour (L(*), a(*), b(*), C(*) and h(*)), water holding capacity (WHC), drip loss (DL), cooking loss (CL) and shear force (SF) in samples packed under two different types of modified atmospheres (MA: MA A: 70%O(2)+30%CO(2); MA B: 69.3%N(2)+30%CO(2)+0.7%CO) at 7, 14 and 21 d post-packaging. The lowest pH was found in G4 and in G5. The highest WHC and the lowest CL were found in G2 and G3 groups (P<0.05). Modified atmospheres did not affect on pH, WHC, CL and DL, although a significant effect (P<0.001) on colour was found at all the analysis times. Both the type of stunning and the modified atmosphere affected SF values. 2009 Elsevier Ltd. All rights reserved.

The effect of sage, sodium erythorbate and a mixture of sage and sodium erythorbate on the quality of turkey meatballs stored under vacuum and modified atmosphere conditions.

PubMed

Karpińska-Tymoszczyk, M

2010-12-01

1. The combined effect of sage (S), sodium erythorbate (SE), a mixture of sage and sodium erythorbate (MIX) and vacuum packaging (VP) and modified atmosphere packaging (MAP) on the quality of cooked turkey meatballs stored at 4°C was investigated. The physicochemical properties (colour, MDA, AV, pH, water activity), microbiological quality characteristics (counts of mesophilic and psychrotrophic bacteria, fungi, coliforms and Clostridium sp.) and flavour attributes of meatballs were determined. 2. The values of the colour parameters L*, a* and b* were affected by the additives and packaging method. The colour of meatballs was better protected by sodium erythorbate than by sage or a mixture of sage and sodium erythorbate. The additives effectively stabilised lipids against oxidation and slowed down hydrolytic changes in turkey meatballs. Sage and a mixture of sage and sodium erythorbate showed stronger antioxidant properties than sodium erythorbate added alone. Products with additives were characterised by better sensory quality than control samples. Sage and MIX prevented the growth of mesophilic and psychrotrophic bacteria. All additives inhibited the growth of coliforms. 3. MAP was more effective than VP in maintaining the microbial and sensory quality stability of cooked turkey meatballs. However, VP appears to be a better method as regards the maintaining of lipid stability in turkey meatballs.

Combined chitosan-thyme treatments with modified atmosphere packaging on a ready-to-cook poultry product.

PubMed

Giatrakou, V; Ntzimani, A; Savvaidis, I N

2010-04-01

In the present study, natural antimicrobials chitosan and thyme, and their combination, were evaluated for their effect on the shelf life of a ready-to-cook (RTC) chicken-pepper kebab (skewer) stored under modified atmosphere packaging (MAP) conditions at 4 +/- 0.5 degrees C for 14 days. The following treatments were examined: control samples stored under aerobic packaging (A), samples stored under MAP (M), samples treated with 1.5% chitosan (vol/wt) and stored under MAP (M-CH), samples treated with 0.2% thyme essential oil (vol/wt) (M-T), and samples treated with 1.5% chitosan (vol/wt) and 0.2% thyme essential oil (vol/wt) and stored under MAP (M-CH-T). Treatment M-CH-T significantly affected aerobic plate counts and counts of lactic acid bacteria, Pseudomonas spp., Brochothrix thermosphacta, Enterobacteriaceae, and yeasts and molds during the entire storage period. Similarly, lipid oxidation of the RTC product was retarded (M-CH-T treatment) during storage, whereas redness was maintained in M-T, M-CH, and M-CH-T samples. Based primarily on sensory data (taste attribute), M-CH and M-T treatments extended RTC product shelf life by 6 days, whereas M-CH-T treatment resulted in a product with a shelf life of 14 days that maintained acceptable sensory characteristics (shelf life of the control was 6 days).

Use of Optical Oxygen Sensors in Non-Destructively Determining the Levels of Oxygen Present in Combined Vacuum and Modified Atmosphere Packaged Pre-Cooked Convenience-Style Foods and the Use of Ethanol Emitters to Extend Product Shelf-Life.

PubMed

Hempel, Andreas W; Papkovsky, Dmitri B; Kerry, Joseph P

2013-11-18

O₂ sensors were used to non-destructively monitor O₂ levels in commercially packed pre-cooked, convenience modified atmosphere packaging (MAP) foods. A substantial level of O₂ (>15%) was present in packs resulting in a shorter than expected shelf-life, where the primary spoilage mechanism was found to be mould. Various combinations of vacuum (0-0.6 MPa) and gas flush (0.02-0.03 MPa) (30% CO₂/70% N₂) settings were assessed as treatments that result in the desired shelf-life (28 days). This was achieved using the combined treatment of vacuum 0.35 MPa and gas flush 0.02 MPa which resulted in a reduction of 6%-9% O 2 in all three samples (battered sausages (BS), bacon slices (BA), and meat and potato pies (PP)). Reduced O₂ levels reflect the microbial quality of products, which has been successfully reduced. Duplicate samples of all product packs were produced using ethanol emitters (EE) to see if shelf-life could be further extended. Results showed a further improvement in shelf-life to 35 days. Sensory analysis showed that ethanol flavour and aroma was not perceived by panellists in two of the three products assessed. This study demonstrates how smart packaging technologies, both intelligent and active, can be used to assist in the modification of conventional packaging systems in order to enhance product quality and safety and through the extension of product shelf-life.

Biosphere-Atmosphere Transfer Scheme (BATS) version le as coupled to the NCAR community climate model. Technical note. [NCAR (National Center for Atmospheric Research)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dickinson, R.E.; Henderson-Sellers, A.; Kennedy, P.J.

A comprehensive model of land-surface processes has been under development suitable for use with various National Center for Atmospheric Research (NCAR) General Circulation Models (GCMs). Special emphasis has been given to describing properly the role of vegetation in modifying the surface moisture and energy budgets. The result of these efforts has been incorporated into a boundary package, referred to as the Biosphere-Atmosphere Transfer Scheme (BATS). The current frozen version, BATS1e is a piece of software about four thousand lines of code that runs as an offline version or coupled to the Community Climate Model (CCM).

Evaluation of sulfur dioxide-generating pads and modified atmosphere packaging for control of postharvest diseases in blueberries

USDA-ARS?s Scientific Manuscript database

Postharvest diseases are a limiting factor of storage and shelf life of blueberries. Gray mold caused by Botrytis cinerea is one of the most important postharvest diseases in blueberries grown in California. In this study, we evaluated the effects of sulfur dioxide (SO2)-generating pads (designated ...

Molecular markers reliably predict post-harvest decay of fresh-cut lettuce in modified atmosphere packaging

USDA-ARS?s Scientific Manuscript database

Fresh-cut lettuce is popular, but highly perishable product. Genetic studies of two bi-parental populations derived from crossing parents with rapid and slow rates of decay showed that the decay rate is heritable (broad spectrum heritability H2 of 0.56 – 0.87). The major genetic determinant of the d...

Dielectric barrier discharge atmospheric cold plasma inhibits Escherichia coli O157:H7, Salmonella, Listeria monocytogenes, and Tulane virus in Romaine lettuce.

PubMed

Min, Sea C; Roh, Si Hyeon; Niemira, Brendan A; Sites, Joseph E; Boyd, Glenn; Lacombe, Alison

2016-11-21

The present study investigated the effects of dielectric barrier discharge atmospheric cold plasma (DACP) treatment on the inactivation of Escherichia coli O157:H7, Salmonella, Listeria monocytogenes, and Tulane virus (TV) on Romaine lettuce, assessing the influences of moisture vaporization, modified atmospheric packaging (MAP), and post-treatment storage on the inactivation of these pathogens. Romaine lettuce was inoculated with E. coli O157:H7, Salmonella, L. monocytogenes (~6logCFU/g lettuce), or TV (~2logPFU/g lettuce) and packaged in either a Petri dish (diameter: 150mm, height: 15mm) or a Nylon/polyethylene pouch (152×254mm) with and without moisture vaporization. Additionally, a subset of pouch-packaged leaves was flushed with O 2 at 5% or 10% (balance N 2 ). All of the packaged lettuce samples were treated with DACP at 34.8kV for 5min and then analyzed either immediately or following post-treatment storage for 24h at 4°C to assess the inhibition of microorganisms. DACP treatment inhibited E. coli O157:H7, Salmonella, L. monocytogenes, and TV by 1.1±0.4, 0.4±0.3, 1.0±0.5logCFU/g, and 1.3±0.1logPFU/g, respectively, without environmental modifications of moisture or gas in the packages. The inhibition of the bacteria was not significantly affected by packaging type or moisture vaporization (p>0.05) but a reduced-oxygen MAP gas composition attenuated the inhibition rates of E. coli O157:H7 and TV. L. monocytogenes continued to decline by an additional 0.6logCFU/g in post-treatment cold storage for 24h. Additionally, both rigid and flexible conventional plastic packages appear to be suitable for the in-package decontamination of lettuce with DACP. Published by Elsevier B.V.

Instrumental meat quality of veal calves reared under three management systems and color evolution of meat stored in three packaging systems.

PubMed

Ripoll, G; Albertí, P; Casasús, I; Blanco, M

2013-02-01

This study evaluated the meat quality of grazing suckling calves (GR), suckling plus supplemented calves (SUP) and weaned calves finished on concentrates (FIN) and the color evolution of meat packaged in film (FILM), modified atmosphere packaging (MAP) and vacuum packaging (VAC). Intramuscular fat was quite low for all treatments and GR meat had greater percentages of PUFA and lower SFA, MUFA and n6/n3 than SUP and FIN. FIN and SUP meat had more L* and was more tender when aged than GR. GR meat was tough and dark. The packaging system was more influential on meat color than the feeding management. VAC had the lowest values of metmyoglobin when aged. MAP had the greatest L* and hue angle and the lowest redness after 13 d of aging, thus MAP was the packaging with the shortest shelf life. Copyright © 2012 Elsevier Ltd. All rights reserved.

Extended shelf life of soy bread using modified atmosphere packaging.

PubMed

Fernandez, Ursula; Vodovotz, Yael; Courtney, Polly; Pascall, Melvin A

2006-03-01

This study investigated the use of modified atmosphere packaging (MAP) to extend the shelf life of soy bread with and without calcium propionate as a chemical preservative. The bread samples were packaged in pouches made from low-density polyethylene (LDPE) as the control (film 1), high-barrier laminated linear low-density polyethylene (LLDPE)-nylon-ethylene vinyl alcohol-nylon-LLDPE (film 2), and medium-barrier laminated LLDPE-nylon-LLDPE (film 3). The headspace gases used were atmosphere (air) as control, 50% CO2-50% N2, or 20% CO2-80% N2. The shelf life was determined by monitoring mold and yeast (M+Y) and aerobic plate counts (APC) in soy bread samples stored at 21 degrees C +/- 3 degrees C and 38% +/- 2% relative humidity. At 0, 2, 4, 6, 8, 10, and 12 days of storage, soy bread samples were removed, and the M+Y and APC were determined. The preservative, the films, and the headspace gases had significant effects on both the M+Y counts and the APC of soy bread samples. The combination of film 2 in the 50% CO2-50% N2 or 20% CO2-80% N2 headspace gases without calcium propionate as the preservative inhibited the M+Y growth by 6 days and the APC by 4 days. It was thus concluded that MAP using film 2 with either the 50% CO2-50% N2 or 20% CO2-80% N2 was the best combination for shelf-life extension of the soy bread without the need for a chemical preservative. These MAP treatments extended the shelf life by at least 200%.

Shelf-life extension of fresh Tuber aestivum and Tuber melanosporum truffles by modified atmosphere packaging with microperforated films.

PubMed

Rivera, Carmen Susana; Blanco, Domingo; Salvador, María Luisa; Venturini, María Eugenia

2010-05-01

The aim of this study was to design a modified atmosphere packaging suitable for Tuber melanosporum and Tuber aestivum truffles that extend their shelf life and their availability as a fresh product. Their respiration rates were determined by O(2) depletion and CO(2) formation in closed systems performed at different temperatures: 4, 10, and 23 degrees C. The results were fitted by exponential equations and derivatives of these equations were used to obtain the experimental respiration rates. Our results revealed high respiration rates in both species of truffles and respiratory quotients (RQ) higher than 1 in all the cases studied. A linear dependence of respiration rate, both R(O2) and R(CO2), on O(2) concentration was revealed. A mathematical model was used to predict the evolution of the gaseous composition at 4 degrees C in the interior of polypropylene trays (250 mL) heat sealed with 4 microperforated films of different transmission rates. A microperforated film with 2 holes (90 x 50 microm) was selected to produce an internal atmosphere of 15%CO(2)/7%O(2) at 4 degrees C. The predicted atmosphere composition was confirmed by the experimental results. The quality and microbiological characteristics of fresh truffles, packaged in these conditions, revealed that the microbial counts of pseudomonads and Enterobacteriaceae were decreased, the weight loss was reduced, the typical hard texture was maintained, and the development of mycelium growth was delayed, enabling good scores for aroma and flavor, and therefore prolonging the shelf life of T. melanosporum and T. aestivum truffles to 28 and 21 d, respectively. Practical Application: This study describes the benefits of using MAP with microperforated films in the postharvest storage of Tuber melanosporum and Tuber aestivum fresh truffles. The shelf life of T. aestivum is prolonged to 21 d and of T. melanosporum to beyond 28 d increasing the possibilities for a foreign market.

Growth and survival of uninjured and sublethally heat-injured Escherichia coli O157:H7 on beef extract medium as influenced by package atmosphere and storage temperature.

PubMed

Semanchek, J J; Golden, D A; Williams, R C

1999-03-01

The effect of atmospheric composition and storage temperature on growth and survival of uninjured and sublethally heat-injured Escherichia coli O157:H7, inoculated onto brain heart infusion agar containing 0.3% beef extract (BEM), was determined. BEM plates were packaged in barrier bags in air, 100% CO2, 100% N2, 20% CO2: 80% N2, and vacuum and were stored at 4, 10, and 37 degrees C for up to 20 days. Package atmosphere and inoculum status (i.e., uninjured or heat-injured) influenced (P < 0.01) growth and survival of E. coli O157:H7 stored at all test temperatures. Growth of heat-injured E. coli O157:H7 was slower (P < 0.01) than uninjured E. coli O157:H7 stored at 37 degrees C. At 37 degrees C, uninjured E. coli O157:H7 reached stationary phase growth earlier than heat-injured populations. Uninjured E. coli O157:H7 grew during 10 days of storage at 10 degrees C, while heat-injured populations declined during 20 days of storage at 10 degrees C. Uninjured E. coli O157:H7 stored at 10 degrees C reached stationary phase growth within approximately 10 days in all packaging atmospheres except CO2. Populations of uninjured and heat-injured E. coli O157:H7 declined throughout storage for 20 days at 4 degrees C. Survival of uninjured populations stored at 4 degrees C, as well as heat-injured populations stored at 4 and 10 degrees C, was enhanced in CO2 atmosphere. Survival of heat-injured E. coli O157:H7 at 4 and 10 degrees C was not different (P > 0.05). Uninjured and heat-injured E. coli O157:H7 are able to survive at low temperatures in the modified atmospheres used in this study.

Comparison between the resistance of benzalkonium chloride-adapted and -nonadapted biofilms of Listeria monocyogenes to modified atmosphere packaging and nisin once transferred to mussels.

PubMed

Saá Ibusquiza, P; Herrera, J J R; Cabo, M L

2011-07-01

Benzalkonium chloride-adapted and -nonadapted Listeria monocytogenes biofilm cells were transferred by contact to cooked or live mussels and packed in rich CO(2) and O(2), respectively. The viabilities of transferred cells during storage of these packed samples at 2.5 °C were compared. In addition, in cooked mussels the combined effect of CO(2) and nisin against the survival of L. monocytogenes was also studied by using a first-order factorial design. The results obtained demonstrated that biofilms formed by benzalkonium chloride-adapted L. monocytogenes cells could be more resistant to the application of modified atmospheres rich in CO(2) and nisin once they have been transferred to cooked mussels by contact (simulating cross-contamination). This implies an increase in the risk associated with the presence of these cells in food processing plants. Significant empirical equations obtained after 7, 11, and 20 days showed an inhibitory effect of CO(2) and nisin against L. monocytogenes. However, a significant positive interaction between both variables highlights an incompatibility between CO(2) and nisin at high concentrations. Results also demonstrated that L. monocytogenes could persist after cross-contamination during the processing of live mussels, so L. monocytogenes is of concern as a contaminant in live mussels packaged in high-O(2) atmospheres. Copyright ©, International Association for Food Protection

Evaluation of a Modified Atmosphere Packaging System to Increase Fresh Fruit and Vegetable Shelf Life for Extended Military Supply Chains

DTIC Science & Technology

2012-02-24

Three key items – iceberg lettuce, romaine lettuce, and broccoli crowns – were tested in the Pacific Region Guam supply chain. Due to longer total...7 2.1.1 Extra Apio Broccoli for Test Shipments 2 and 3 ................................................8 2.2 Test...49 3.3 Broccoli Crowns .............................................................................................................49 3.3.1

Effectiveness of antimicrobial food packaging materials.

PubMed

Cooksey, K

2005-10-01

Antimicrobial additives have been used successfully for many years as direct food additives. The literature provides evidence that some of these additives may be effective as indirect food additives incorporated into food packaging materials. Antimicrobial food packaging is directed toward the reduction of surface contamination of processed, prepared foods such as sliced meats and Frankfurter sausages (hot dogs). The use of such packaging materials is not meant to be a substitute for good sanitation practices, but it should enhance the safety of food as an additional hurdle for the growth of pathogenic and/or spoilage microorganisms. Studies have focused on establishing methods for coating low-density polyethylene film or barrier films with methyl cellulose as a carrier for nisin. These films have significantly reduced the presence of Listeria monocytogenes in solutions and in vacuum packaged hot dogs. Other research has focused on the use of chitosan to inhibit L. monocytogenes and chlorine dioxide sachets for the reduction of Salmonella on modified atmosphere-packaged fresh chicken breasts. Overall, antimicrobial packaging shows promise as an effective method for the inhibition of certain bacteria in foods, but barriers to their commercial implementation continue to exist.

Effect of Various Packaging Methods on Small-Scale Hanwoo (Korean Native Cattle) during Refrigerated Storage

PubMed Central

Yu, Hwan Hee; Song, Myung Wook; Kim, Tae-Kyung; Choi, Yun-Sang; Cho, Gyu Yong; Lee, Na-Kyoung; Paik, Hyun-Dong

2018-01-01

Abstract The objective of this study was to investigate comparison of physicochemical, microbiological, and sensory characteristics of Hanwoo eye of round by various packaging methods [wrapped packaging (WP), modified atmosphere packaging (MAP), vacuum packaging (VP) with three different vacuum films, and vacuum skin packaging (VSP)] at a small scale. Packaged Hanwoo beef samples were stored in refrigerated conditions (4±1°C) for 28 days. Packaged beef was sampled on days 0, 7, 14, 21, and 28. Physicochemical [pH, surface color, thiobarbituric acid reactive substances (TBARS), and volatile basic nitrogen (VBN) values], microbiological, and sensory analysis of packaged beef samples were performed. VP and VSP samples showed low TBARS and VBN values, and pH and surface color did not change substantially during the 28-day period. For VSP, total viable bacteria, psychrotrophic bacteria, lactic acid bacteria, and coliform counts were lower than those for other packaging systems. Salmonella spp. and Escherichia coli O157:H7 were not detected in any packaged beef samples. A sensory analysis showed that the scores for appearance, flavor, color, and overall acceptability did not change significantly until day 7. In total, VSP was effective with respect to significantly higher a* values, physicochemical stability, and microbial safety in Hanwoo packaging (p<0.05). PMID:29805283

Synergistic effect of spice extracts and modified atmospheric packaging towards non-thermal preservation of chicken meat under refrigerated storage.

PubMed

Sivarajan, M; Lalithapriya, U; Mariajenita, Peter; Vajiha, B Aafrin; Harini, K; Madhushalini, D; Sukumar, M

2017-08-01

This study investigates the integrated approach of spice extracts and modified atmospheric packaging (MAP) chicken meat preservation. Specifically, extracts from clove (CL), cinnamon (CI) individually and in combination (3% w/w) along with MAP (30% CO2/70% N2 and 10% O2/30% CO2/60% N2) were used to increase the shelf life of fresh chicken meat stored at 4°C. The parameters evaluated as shelf life indications are microbiological (total viable count, Pseudomonas spp., lactic acid bacteria (LAB), and Enterobacteriaceae), physicochemical (pH, Lipid oxidation, color changes) and Sensory attributes. Microbial population were reduced by 2.5 to 5 log cfu/g, with the greater impact being accomplished by the blend of clove and cinnamon extract with 30% CO2/70% N2 MAP. Thiobarbituric values for all treated and MAP packed samples remained lower than 1 mg malondialdehyde (MDA)/kg all through the 24 day storage period. pH values varied from 5.5 for fresh sample on day 0 to 7.11 (day 25) on combined extract treated and MAP packaged samples. The estimations of the color parameters L*, a*, and b* were well maintained in oxygen deficient MAP. Finally, sensory investigation demonstrated that combined clove and cinnamon extract of 3% conferred acceptable sensory attributes to the samples on day 24 of storage. These results indicate the extended shelf life of chicken meat from 4 days to 24 days for samples when coated with 3% of combined clove and cinnamon extract and packaged under MAP without oxygen. These pooled extracts along with MAP displayed expanded the usability and the organoleptic qualities of chicken meat. © 2017 Poultry Science Association Inc.

Shelf life extension of lamb meat using thyme or oregano essential oils and modified atmosphere packaging.

PubMed

Karabagias, I; Badeka, A; Kontominas, M G

2011-05-01

The effect of thyme (TEO) and oregano (OEO) essential oils as well as modified atmosphere packaging (MAP) in extending the shelf life of fresh lamb meat stored at 4 °C was investigated. In a preliminary experiment TEO and OEO were used at concentrations 0.1 and 0.3% v/w while MAP tested included MAP1 (60% CO(2)/40% N(2)) and MAP2 (80% CO(2)/20% N(2)). Microbiological, physicochemical and sensory properties of lamb meat were monitored over a 20 day period. Sensory analysis showed that at the higher concentration both essential oils gave a strong objectionable odour and taste and were not further used. Of the two essential oils TEO was more effective as was MAP2 over MAP1 for lamb meat preservation. In a second experiment the combined effect of TEO (0.1%) and MAP2 (80/20) on shelf life extension of lamb meat was evaluated over a 25 day storage period. Microbial populations were reduced up to 2.8 log cfu/g on day 9 of storage with the most pronounced effect being achieved by the combination MAP2 plus TEO (0.1%). TBA values varied for all treatments and remained lower than 4 mg MDA/kg throughout storage. pH values varied between 6.4 and 6.0 during storage. Color parameters (L and b) increased with storage time while parameter (a) remained unaffected. Based primarily on sensory analysis (odour) but also on microbiological data, shelf life of lamb meat was 7 days for air packaged samples, 9-10 days for samples containing 0.1% of TEO and 21-22 days for MAP packaged samples containing 0.1% TEO. Copyright © 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

Use of Optical Oxygen Sensors in Non-Destructively Determining the Levels of Oxygen Present in Combined Vacuum and Modified Atmosphere Packaged Pre-Cooked Convenience-Style Foods and the Use of Ethanol Emitters to Extend Product Shelf-Life

PubMed Central

Hempel, Andreas W.; Papkovsky, Dmitri B.; Kerry, Joseph P.

2013-01-01

O2 sensors were used to non-destructively monitor O2 levels in commercially packed pre-cooked, convenience modified atmosphere packaging (MAP) foods. A substantial level of O2 (>15%) was present in packs resulting in a shorter than expected shelf-life, where the primary spoilage mechanism was found to be mould. Various combinations of vacuum (0–0.6 MPa) and gas flush (0.02–0.03 MPa) (30% CO2/70% N2) settings were assessed as treatments that result in the desired shelf-life (28 days). This was achieved using the combined treatment of vacuum 0.35 MPa and gas flush 0.02 MPa which resulted in a reduction of 6%–9% O2 in all three samples (battered sausages (BS), bacon slices (BA), and meat and potato pies (PP)). Reduced O2 levels reflect the microbial quality of products, which has been successfully reduced. Duplicate samples of all product packs were produced using ethanol emitters (EE) to see if shelf-life could be further extended. Results showed a further improvement in shelf-life to 35 days. Sensory analysis showed that ethanol flavour and aroma was not perceived by panellists in two of the three products assessed. This study demonstrates how smart packaging technologies, both intelligent and active, can be used to assist in the modification of conventional packaging systems in order to enhance product quality and safety and through the extension of product shelf-life. PMID:28239134

Effects of innovative and conventional sanitizing treatments on the reduction of Saccharomycopsis fibuligera defects on industrial durum wheat bread.

PubMed

Giannone, Virgilio; Pitino, Iole; Pecorino, Biagio; Todaro, Aldo; Spina, Alfio; Lauro, Maria Rosaria; Tomaselli, Filippo; Restuccia, Cristina

2016-10-17

Wickerhamomyces anomalus, Hyphopichia burtonii and Saccharomycopsis fibuligera are spoilage yeasts causing chalk mold defects on sliced bread packaged under modified atmosphere. The first objective of this study, carried out in a bread-making company for two consecutive years, was to genetically identify yeasts isolated from spoiled sliced bread in Modified Atmosphere Packaging (MAP) and to determine the dominant species among identified strains. The second objective was to evaluate the effects of hydrogen peroxide and silver solution 12% (HPS) treatment in the leavening cells and cooling chambers, in comparison with the conventional Ortho-Phenylphenol (OPP) fumigating treatment, on the incidence of chalk defects of the commercialized products. One-hundred percent of the isolated yeasts were identified as S. fibuligera, while H. burtonii and W. anomalus were not detected. Concerning mean water activity (aw) and moisture content values, packaged bread samples were, respectively, included in the range 0.922-0.940 and 33.40-35.39%. S. fibuligera was able to grow in a wide range of temperature (11.5 to 28.5°C) and relative humidity (70.00 to 80.17%) in the processing environments, and product aw<0.94. Compared to OPP, the combined treatment with hydrogen peroxide and silver solution, in association with MAP, reduced to a negligible level yeast contamination of industrial sliced bread. The identification of the spoilage organisms and a comprehensive understanding of the combined effects of aw, pO2/pCO2 inside the packages, environmental conditions and sanitizing treatment on the growth behaviour is essential for future development of adequate preventive process strategies against chalk mold defects. Copyright © 2016 Elsevier B.V. All rights reserved.

Effect of modified atmosphere packaging on quality and shelf life of 'Robusta' banana (Musa sp.) stored at low temperature.

PubMed

Kudachikar, V B; Kulkarni, S G; Prakash, M N Keshava

2011-06-01

Banana (Musa sp var. 'Robusta') stored under active and passive modified atmosphere packaging (MAP) at 12 ± 1°C and 85-90% RH for 2 seasons were evaluated for fruit quality and shelf-life. A steady state of about 8.6 and 8.2% of CO2 and 2.8 and 2.6% of O2 in passive MAP and MAP+GK (Green Keeper) packages, respectively, were established after 3 weeks of storage. Passive MAP and MAP+GK treatments of banana resulted in reduction in physiological loss in weight (PLW) of 0.7 and 0.8% after 5 and 7 weeks of storage, respectively as against 5% PLW in openly kept green banana after 3 weeks. Both MAP and MAP+GK treatments delayed colour, texture, pulp to peel ratio and total soluble solids (TSS) content as compared to openly kept control banana. Results indicated that the shelf life of fruits packed under MAP and MAP+GK could be extended up to 5 and 7 weeks, respectively as compared to 3 weeks for openly kept control fruits. Sensory quality of fully ripe fruits of both passive MAP and MAP+GK treatments, 5 days after ethrel dip was very good. Thus, MAP+GK at 12 ± 1°C and 85-90% RH could be commercially used for long term storage and long distance transportation of banana with maximum shelf-life of 7 weeks.

Display stability of fresh and thawed lamb supplemented with vitamin E or sprayed with an antioxidant borage seed extract.

PubMed

Bellés, Marc; Alonso, Verónica; Roncalés, Pedro; Beltrán, Jose A

2018-06-01

The commercialization of thawed lamb packaged in modified atmosphere and maintained on display could serve as an alternative capable of satisfying the requirements of both customers and distributors. However, previous studies have suggested that lipid oxidation may accelerate post-thawing because peroxidation occurs during frozen storage, thereby leading to rapid and severe secondary lipid oxidation. The addition of an antioxidant compound either in the lamb diet or in the packaged meat could resolve this problem. Therefore, the present study aimed to compare the effect of dietary vitamin E (1000 mg of dl-α-tocopheryl acetate per kg of basal diet) and the spraying of borage seed aqueous extract (10% p/v) on the quality of fresh and thawed lamb leg chops. Both borage extract and vitamin E improved colour (as measured via instrumental and visual assessment of colour) and lipid stability (thiobarbituric acid reactive substances) of fresh and thawed lamb throughout display, although neither of them had any antimicrobial effect. Freezing/thawing accelerated bone marrow darkening and reduced redness but delayed microbial growth. Both of these antioxidant strategies would be very profitable for the preservation of lamb meat, allowing thawed meat packaged in a modified atmosphere to be commercialized. However, additional studies should be carried out to determine how bone darkening in thawed chops can be avoided. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Trends in microbial control techniques for poultry products.

PubMed

Silva, Filomena; Domingues, Fernanda C; Nerín, Cristina

2018-03-04

Fresh poultry meat and poultry products are highly perishable foods and high potential sources of human infection due to the presence of several foodborne pathogens. Focusing on the microbial control of poultry products, the food industry generally implements numerous preventive measures based on the Hazard Analysis and Critical Control Points (HACCP) food safety management system certification together with technological steps, such as refrigeration coupled to modified atmosphere packaging that are able to control identified potential microbial hazards during food processing. However, in recent years, to meet the demand of consumers for minimally processed, high-quality, and additive-free foods, technologies are emerging associated with nonthermal microbial inactivation, such as high hydrostatic pressure, irradiation, and natural alternatives, such as biopreservation or the incorporation of natural preservatives in packaging materials. These technologies are discussed throughout this article, emphasizing their pros and cons regarding the control of poultry microbiota and their effects on poultry sensory properties. The discussion for each of the preservation techniques mentioned will be provided with as much detail as the data and studies provided in the literature for poultry meat and products allow. These new approaches, on their own, have proved to be effective against a wide range of microorganisms in poultry meat. However, since some of these emergent technologies still do not have full consumer's acceptability and, taking into consideration the hurdle technology concept for poultry processing, it is suggested that they will be used as combined treatments or, more frequently, in combination with modified atmosphere packaging.

Toward shrimp consumption without chemicals: Combined effects of freezing and modified atmosphere packaging (MAP) on some quality characteristics of Giant Red Shrimp (Aristaeomorpha foliacea) during storage.

PubMed

Bono, Gioacchino; Okpala, Charles Odilichukwu R; Alberio, Giuseppina R A; Messina, Concetta M; Santulli, Andrea; Giacalone, Gabriele; Spagna, Giovanni

2016-04-15

The combined effects of freezing and modified atmosphere packaging (MAP) (100% N2 and 50% N2+50% CO2) on some quality characteristics of Giant Red Shrimp (GRS) (Aristaeomorpha foliacea) was studied during 12-month storage. In particular, the quality characteristics determined proximal and gas compositions, melanosis scores, pH, total volatile basic-nitrogen (TVB-N), thiobarbituric acid (TBA) as well as free amino acid (FAA). In addition, the emergent data were compared to those subject to vacuum packaging as well as conventional preservative method of sulphite treatment (SUL). Most determined qualities exhibited quantitative differences with storage. By comparisons, while pH and TVB-N statistically varied between treatments (P<0.05) and TBA that ranged between ∼0.15 and 0.30 mg MDA/kg appeared least at end of storage for 100% N2 treated-group, the latter having decreased melanosis scores showed such treatments with high promise to keep the colour of GRS sample hence, potential replacement for SUL group. By comparisons also, while some individual FAA values showed increases especially at the 100% N2-treated group, the total FAAs statistically differed with storage (P<0.05). The combination of freezing and MAP treatments as preservative treatment method shows high promise to influence some quality characteristics of GRS samples of this study. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microbial growth, communities and sensory characteristics of vacuum and modified atmosphere packaged lamb shoulders.

PubMed

Kiermeier, Andreas; Tamplin, Mark; May, Damian; Holds, Geoff; Williams, Michelle; Dann, Alison

2013-12-01

Packaging fresh lamb in a vacuum (VAC) versus a 100% CO2 modified atmosphere (MAP) may influence product shelf-life and the bacterial communities. While VAC is a common packing method and 100% CO2 MAP is used in some countries, there is little information about how these different techniques affect the growth of spoilage bacteria and sensory attributes of lamb. The aim of this study was to assess changes in microbiological and organoleptic properties, and determine differences in microbial communities by terminal restriction fragment length polymorphism (TRFLP) and 454 pyrosequencing, in bone-in (BI) and bone-out (BO) MAP- and VAC-packed lamb shoulders stored at -0.3 °C over 12 wk. VAC and MAP lamb shoulders were acceptable in sensory test scores over 12 wk of storage at -0.3 °C, despite total viable count (TVC) and lactic acid bacteria (LAB) levels increasing to 8 log10 CFU/cm(2) for VAC lamb and 4-6 log10 CFU/cm(2) for MAP lamb. Similar to the sensory results, there were no significant differences in microbial communities between BI and BO product. However, types of bacteria were different between VAC and MAP packaging. Specifically, while VAC shoulder became dominated by Carnobacterium spp. in the middle of the storage period, the MAP shoulder microbial population remained similar from the start until later storage times. Copyright © 2013 Elsevier Ltd. All rights reserved.

Comparison of argon-based and nitrogen-based modified atmosphere packaging on bacterial growth and product quality of chicken breast fillets.

PubMed

Herbert, Ulrike; Rossaint, Sonja; Khanna, Meik-Ankush; Kreyenschmidt, Judith

2013-05-01

Poultry fillets were packaged under 6 different gas atmospheres (A: 15% Ar, 60% O2, 25% CO2; B: 15% N2, 60% O2, 25% CO2; C: 25% Ar, 45% O2, 30% CO2; D: 25% N2, 45% O2, 30% CO2; E: 82% Ar; 18% CO2; F: 82% N2, 18% CO2) and stored at 4°C. During storage, the growth of typical spoilage organisms (Brochothrix thermosphacta, Pseudomonas spp., Enterobacteriaceae, and Lactobacilli spp.) and total viable count were analyzed and modeled using the Gompertz function. Sensory analyses of the poultry samples were carried out by trained sensory panelists for color, odor, texture, drip loss, and general appearance. No significant difference in microbiological growth parameters was observed for fresh poultry stored under an argon-enriched atmosphere in comparison with nitrogen, except the B. thermosphacta stored under 82% argon. The sensory evaluation showed a significant effect of an argon-enriched atmosphere, particularly on color of meat stored under 15% argon (P < 0.05). In contrast, 25 and 82% argon concentrations in place of nitrogen showed no beneficial effect on sensory parameters.

Behavior of flavonols and carotenoids of minimally processed kale leaves during storage in passive modified atmosphere packaging.

PubMed

Kobori, C N; Huber, L S; Sarantópoulos, C I G L; Rodriguez-Amaya, D B

2011-03-01

Minimally processed kale leaves were packed in passive modified atmosphere and stored at 3 conditions: 1 °C in the dark and 11 °C with or without light exposure. The products were evaluated during storage in terms of headspace gas composition, sensory attributes, flavonol, and carotenoid contents. The sensory quality decreased slightly during 17 d at 1 °C in the dark. At 11 °C, the vegetable shelf life was predicted to be 6 d in the dark and 3 d with light. Quercetin and kaempferol were stable during storage for 15 d at 1 °C in the absence of light. At 11 °C in the dark, quercetin was stable during 10 d, increasing slightly on the 8th day. Kaempferol decreased up to the 5th day but increased on the 8th day, decreasing again on the 10th day. After 5 d at 11 °C under light, the flavonol levels were significantly higher than those of the initial values. Neoxanthin and violaxanthin did not change significantly after 15 d at 1 °C in the dark. Lutein and β-carotene, however, decreased 7.1% and 11.3%, respectively. At 11 °C in the dark, neoxanthin, violaxanthin, lutein, and β-carotene decreased 16.1%, 13.2%, 24.1%, and 23.7% after 10 d, respectively. At 11 °C under light, neoxanthin and lutein had a slight increase while violaxanthin and β-carotene decreased 23.1% and 16.5% after 5 d. Practical Application:  Passive modified atmosphere packaging together with refrigeration can extend the shelf life of minimally processed kale, retaining the health-promoting compounds, flavonols and carotenoids. Quercetin, kaempferol, neoxanthin, and violaxanthin are stable and lutein and β-carotene slightly reduced.

The effect of post-harvest and packaging treatments on glucoraphanin concentration in broccoli (Brassica oleracea var. italica).

PubMed

Rangkadilok, Nuchanart; Tomkins, Bruce; Nicolas, Marc E; Premier, Robert R; Bennett, Richard N; Eagling, David R; Taylor, Paul W J

2002-12-04

The effects of post-harvest and packaging treatments on glucoraphanin (4-methylsulfinylbutyl glucosinolate), the glucosinolate precursor of anticancer isothiocyanate sulforaphane [4-methylsulfinylbutyl isothiocyanate], were examined in broccoli (Brassica oleracea var. italica) during storage times. The results showed that at 20 degrees C, 55% loss of glucoraphanin concentration occurred in broccoli stored in open boxes during the first 3 days of the treatment and 56% loss was found in broccoli stored in plastic bags by day 7. Under both air and controlled atmosphere (CA) storage, glucoraphanin concentration appeared to fluctuate slightly during 25 days of storage and the concentrations under CA was significantly higher than those stored under air treatment. In modified atmosphere packaging (MAP) treatments, glucoraphanin concentration in air control packaging decreased significantly whereas there were no significant changes in glucoraphanin concentration in MAP with no holes at 4 degrees C and two microholes at 20 degrees C for up to 10 days. Decreases in glucoraphanin concentration occurred when the broccoli heads deteriorated. In the present study, the best method for preserving glucoraphanin concentration in broccoli heads after harvest was storage of broccoli in MAP and refrigeration at 4 degrees C. This condition maintained the glucoraphanin concentration for at least 10 days and also maintained the visual quality of the broccoli heads.

Acids in combination with sodium dodecyl sulfate caused quality deterioration of fresh-cut iceburg lettuce during storage in modified atmosphere package

USDA-ARS?s Scientific Manuscript database

Recent studies showed that levulinic acid (LA) and sodium acid sulfate (SAS) were effective in inactivating human pathogens on fresh produce. The present study investigated the effects of LA and SAS in comparison with citric acid and chlorine on the inactivation of E. coli O157:H7 and the sensory qu...

Influence of modified atmospheric storage, lactic acid, and NaCl on survival of sublethally heat-injured Listeria monocytogenes.

PubMed

Williams, R C; Golden, D A

2001-03-20

The effect of package atmosphere on survival of uninjured and sublethally heat-injured Listeria monocytogenes, inoculated onto tryptose phosphate agar containing 0.85% lactic acid and 2% NaCl (TPALAS) was investigated. Inoculated TPALAS plates were packaged in air, 100% N2 (N2), 30% CO2-70% N2 (CO2-N2), and vacuum and stored at 4 and 20 degrees C for up to 31 days. Recovery of L. monocytogenes from TPALAS was influenced by the injury status (i.e., injured and uninjured) of the inoculum, storage atmosphere (air, N2, CO2-N2, and vacuum), storage temperature (4 and 20 degrees C), and recovery media [tryptose phosphate agar (TPA) and modified Oxford agar (MOX)] (P <0.05). Overall, storage at 4 degrees C supported greater survival than storage at 20 degrees C (P< 0.05). Uninjured L. monocytogenes stored at 4 degrees C was recovered on TPA better than sublethally heat-injured L. monocytogenes stored at 40 degrees C (P < 0.05). Recovery of sublethally heat-injured L. monocytogenes stored at 4 degrees C followed the order N2 > CO2-N2 > air > vacuum (P < 0.05), whereas recovery of uninjured L. monocyrogenes stored at 4 degrees C followed the order N2 > CO2-N2 > vacuum > air (P < 0.05). Air and vacuum atmospheres supported greater survival of uninjured and heat-injured L. monocytogenes than N2 and CO2-N2 atmospheres at 20 degrees C (P < 0.05). Recovery of sublethally heat-injured L. monocytogenes stored at 20 degrees C followed the order vacuum > air> CO2-N2 = N2 (P <0.05), whereas recovery of uninjured L. monocytogenes stored at 20 degrees C followed the order vacuum > air> CO2-N2 > N2 (P<0.05). Uninjured L. monocytogenes stored under N2 at 4 degrees C was recovered best, whereas sublethally heat-injured L. monocytogenes stored under N2 at 20 degrees C was recovered poorest (P < 0.05). Factors such as package atmosphere and storage temperature, involved in the production, storage, and distribution of fermented foods must be thoroughly evaluated when determining strategies for control and detection of L. monocytogenes in such products.

Retail colour stability of lamb meat is influenced by breed type, muscle, packaging and iron concentration.

PubMed

Warner, R D; Kearney, G; Hopkins, D L; Jacob, R H

2017-07-01

The longissmus lumborum (LL) and semimembranosus (SM) muscles from 391 lamb carcasses, derived from various breed types, were used to investigate the effect of animal/muscle factors, packaging type [over-wrap (OW) or high oxygen modified atmosphere packaging (MAP O2 )] and duration of display on redness of meat during simulated retail display. Using statistical models the time required (in days) for redness to reach a threshold value of 3.5 (below this is unacceptable) was predicted. High levels of iron in the SM, but not LL, reduced the time for redness to reach 3.5 by 2-2.6days in MAP O2 and 0.5-0.8days in OW. The greater the proportion of Merino breed type, the shorter was the time for redness to reach the value of 3.5, an effect consistent across muscles and packaging types. In summary, breed type, packaging format, muscle and muscle iron levels had a significant impact on colour stability of sheep meat in oxygen-available packaging systems. Copyright © 2017. Published by Elsevier Ltd.

Biotechnological Approach To Preserve Fresh Pasta Quality.

PubMed

Angiolillo, L; Conte, A; Del Nobile, M A

2017-12-01

Fresh pasta is highly susceptible to microbial contamination because of its high water activity and nutrient content. In this study, a new biopreservation system was examined that consists of an active sodium alginate solution containing Lactobacillus reuteri and glycerol, which was added during the production process of pasta. Our aim was to extend the fresh pasta shelf life by the in situ production of reuterin, thereby avoiding the use of thermal treatments that generally compromise food sensory characteristics. Two experimental studies were carried out with the product packaged under either ordinary or modified atmospheric conditions. Microbiological and sensory quality indices were monitored to determine the effectiveness of biopreservation on product quality during storage. The use of the active solution with L. reuteri and glycerol during the production process of pasta improved both microbial and sensory quality, particularly when combined with modified atmosphere.

Effects of extended aging and modified atmospheric packaging on beef top loin steak color.

PubMed

English, A R; Mafi, G G; VanOverbeke, D L; Ramanathan, R

2016-04-01

The objective of this study was to evaluate the effects of extended aging and modified atmospheric packaging on beef LM color. Using a randomized complete block design, each beef longissimus lumborum muscle ( = 10; USDA Choice, 3 d postmortem) was equally divided into 3 sections and randomly assigned to 1 of 3 aging periods (21, 42, or 62 d at 2°C). After respective aging, each loin section was cut into four 2.5-cm-thick steaks and randomly assigned to 1 of 3 packaging types (PVC, HiOx-MAP [80% oxygen and 20% carbon dioxide], or CO-MAP [0.4% carbon monoxide, 69.6% nitrogen, and 30% carbon dioxide]). The steaks were displayed under continuous fluorescent lighting for 6 d, and surface color was determined daily using a HunterLab Miniscan XE Plus spectrophotometer and a visual panel. The fourth steak was used to characterize oxygen consumption (OC), lipid oxidation, and metmyoglobin reducing activity (MRA) on 21, 42, and 62 d (before display). On d 6 display, MRA, OC, and lipid oxidation also were measured. An increase in aging time decreased ( < 0.0001) muscle pH. Loin sections aged for 42 and 62 d had a lower ( < 0.0002) pH compared with loin sections aged for 21 d. An aging period × packaging × display time interaction ( < 0.0001) resulted for a* values (redness), chroma, and visual color (muscle color and surface discoloration). As aging time increased, HiOx-MAP had the most discoloration ( < 0.0001) compared with other packaging types on d 6. At all aging periods, steaks packaged in CO-MAP had greater ( < 0.0001) MRA on d 6 than PVC and HiOx-MAP, whereas steaks packaged in HiOx-MAP had the least MRA ( < 0.0001). There were no differences ( = 0.34) in thiobarbituric acid reactive substances values between steaks aged for 21 and 42 d when steaks were packaged in CO-MAP and displayed for 6 d. However, steaks packaged in HiOx-MAP and displayed 6 d had greater ( < 0.0001) lipid oxidation than CO-MAP. Steaks packaged in HiOx-MAP had a lower ( < 0.0001) OC compared with PVC and CO-MAP when aged for 42 and 62 d. There were no differences ( = 0.49) in OC between steaks packaged in PVC and HiOx-MAP when aged for 21 d and displayed 6 d. The results indicate that extended aging is detrimental to color stability when packaged in PVC and HiOx-MAP. However, steaks in CO-MAP had stable red color during display. Decreased color stability in PVC and HiOx-MAP could be associated, in part, with decreased MRA and OC.

Antioxidant synergism between tocopherols and ascorbyl palmitate in cooked, minced turkey.

PubMed

Bruun-Jensen, L; Skovgaard, I M; Skibsted, L H; Bertelsen, G

1994-09-01

In an attempt to reduce oxidative deterioration, including the development of warmed-over flavour (WOF), in cooked, minced turkey meat, a combined strategy using natural antioxidants and modified atmosphere packaging (MAP) was adapted. Tocopherols (200 ppm) each significantly reduced lipid oxidation during 9 days of cold storage (5 degrees C), measured as 2-thiobarbituric-acid-reactive substances (TBARS). Synergism between the two antioxidants was demonstrated as an increasing relative reduction in TBARS values over time when both antioxidants were added, as opposed to the almost constant relative reduction when only one antioxidant was added. Notably, this synergism depended on the availability of O2, and was found to be most significant for atmospheric packaging (21% O2, 79% N2) and most significant towards the end of the storage period. A reduced O2 content in the packages (mixture of O2 and N2, initially: 1.0% O2 or 0.03% O2) had a more pronouced effect on oxidative deterioration than addition of antioxidants. However, during the 9 days of storage, meat balls with the synergistic mixture added, and packed in 1% O2, had TBARS values of 50 compared to 270 mumol malondialdehyde/kg for meat balls without antioxidants packed in 21% O2. This level of reduction in lipid oxidation is comparable with that of meat balls without antioxidants packed in a virtually O2-free atmosphere.

Development of the physics driver in NOAA Environmental Modeling System (NEMS)

NASA Astrophysics Data System (ADS)

Lei, H.; Iredell, M.; Tripp, P.

2016-12-01

As a key component of the Next Generation Global Prediction System (NGGPS), a physics driver is developed in the NOAA Environmental Modeling System (NEMS) in order to facilitate the research, development, and transition to operations of innovations in atmospheric physical parameterizations. The physics driver connects the atmospheric dynamic core, the Common Community Physics Package and the other NEMS-based forecast components (land, ocean, sea ice, wave, and space weather). In current global forecasting system, the physics driver has incorporated major existing physics packages including radiation, surface physics, cloud and microphysics, ozone, and stochastic physics. The physics driver is also applicable to external physics packages. The structure adjustment in NEMS by separating the PHYS trunk is to create an open physics package pool. This open platform is beneficial to the enhancement of U.S. weather forecast ability. In addition, with the universal physics driver, the NEMS can also be used for specific functions by connecting external target physics packages through physics driver. The test of its function is to connect a physics dust-radiation model in the system. Then the modified system can be used for dust storm prediction and forecast. The physics driver is also developed into a standalone form. This is to facilitate the development works on physics packages. The developers can save instant fields of meteorology data and snapshots from the running system , and then used them as offline driving data fields to test the new individual physics modules or small modifications to current modules. This prevents the run of whole system for every test.

The Effect of Modified Atmosphere Packaging and Addition of Rosemary Extract, Sodium Acetate and Calcium Lactate Mixture on the Quality of Pre-cooked Hamburger Patties during Refrigerated Storage

PubMed Central

Muhlisin; Kang, Sun Moon; Choi, Won Hee; Lee, Keun Taik; Cheong, Sung Hee; Lee, Sung Ki

2013-01-01

The effect of modified atmosphere packaging (MAP; 30% CO2+70% N2 or 100% N2) and an additive mixture (500 ppm rosemary extract, 3,000 ppm sodium acetate and 1,500 ppm calcium lactate) on the quality of pre-cooked hamburger patties during storage at 5°C for 14 d was evaluated. The addition of the additive mixture reduced aerobic and anaerobic bacteria counts in both 30% CO2-MAP (30% CO2+70% N2) and 100% N2-MAP (p<0.05). The 30% CO2-MAP was more effective to suppress the microbial growth than 100% N2-MAP, moreover the 30% CO2-MAP combined with additive mixture resulted in the lowest bacterial counts. The hamburger patties with additive mixture showed lower CIE L* and CIE a*, and higher CIE b* than those with no additive mixture. The 30% CO2-MAP tended to decrease the TBARS during storage regardless of the addition of additives. The use of 30% CO2-MAP in combination with additives mixture was effective for maintaining the quality and extending the shelf-life of pre-cooked hamburger patties. PMID:25049716

Immature pea seeds: effect of storage under modified atmosphere packaging and sanitation with acidified sodium chlorite.

PubMed

Collado, Elena; Venzke Klug, Tâmmila; Martínez-Sánchez, Ascensión; Artés-Hernandez, Francisco; Aguayo, Encarna; Artés, Francisco; Fernández, Juan A; Gómez, Perla A

2017-10-01

Appropriate sanitation is a priority for extending the shelf life and promoting the consumption of immature pea seeds, as processing accelerates quality deterioration and microbial growth. The combined effect of disinfection with acidified sodium chlorite (ASC) or sodium hypochlorite (SH) and packaging under a passive modified atmosphere (MAP) at 1 or 4 °C on quality was analysed. After 14 days, greenness and vitamin C had decreased, especially in the SH-disinfected samples. Total phenols and antioxidant capacity were not affected by disinfection. Proteins levels fell by around 27%, regardless of the sanitizer and storage temperature. Compared with the initial microbial load, samples stored at 1 °C showed an increase of 1 log CFU g -1 in psychrophiles when treated with SH, whereas no increase of note occurred with ASC. In general, microbial counts were always below 3 log CFU g -1 for all the treatments. Immature pea seeds could be stored for 14 days at 1-4 °C under MAP with only minor quality changes. Disinfection with ASC resulted in better sensory quality, higher content of vitamin C and lower psychrophile counts. More research is needed to analyse the effect of these treatments on other quality parameters. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Modified atmosphere packaging for prevention of mold spoilage of bakery products with different pH and water activity levels.

PubMed

Guynot, M E; Marín, S; Sanchis, V; Ramos, A J

2003-10-01

A sponge cake analog was used to study the influence of pH, water activity (aw), and carbon dioxide (CO2) levels on the growth of seven fungal species commonly causing bakery product spoilage (Eurotium amstelodami, Eurotium herbariorum, Eurotium repens, Eurotium rubrum, Aspergillus niger, Aspergillus flavus, and Penicillium corylophilum). A full factorial design was used. Water activity, CO2, and their interaction were the main factors significantly affecting fungal growth. Water activity at levels of 0.80 to 0.90 had a significant influence on fungal growth and determined the concentration of CO2 needed to prevent cake analog spoilage. At an aw level of 0.85, lag phases increased twofold when the level of CO2 in the headspace increased from 0 to 70%. In general, no fungal growth was observed for up to 28 days of incubation at 25 degrees C when samples were packaged with 100% CO2, regardless of the aw level. Partial least squares projection to latent structures regression was used to build a polynomial model to predict sponge cake shelf life on the basis of the lag phases of all seven species tested. The model developed explained quite well (R2 = 79%) the growth of almost all species, which responded similarly to changes in tested factors. The results of this study emphasize the importance of combining several hurdles, such as modified atmosphere packaging, aw, and pH, that have synergistic or additive effects on the inhibition of mold growth.

Reducing Salt in Raw Pork Sausages Increases Spoilage and Correlates with Reduced Bacterial Diversity

PubMed Central

Fougy, Lysiane; Desmonts, Marie-Hélène; Coeuret, Gwendoline; Fassel, Christine; Hamon, Erwann; Hézard, Bernard; Champomier-Vergès, Marie-Christine

2016-01-01

ABSTRACT Raw sausages are perishable foodstuffs; reducing their salt content raises questions about a possible increased spoilage of these products. In this study, we evaluated the influence of salt reduction (from 2.0% to 1.5% [wt/wt]), in combination with two types of packaging (modified atmosphere [50% mix of CO2-N2] and vacuum packaging), on the onset of spoilage and on the diversity of spoilage-associated bacteria. After 21 days of storage at 8°C, spoilage was easily observed, characterized by noticeable graying of the products and the production of gas and off-odors defined as rancid, sulfurous, or sour. At least one of these types of spoilage occurred in each sample, and the global spoilage intensity was more pronounced in samples stored under modified atmosphere than under vacuum packaging and in samples with the lower salt content. Metagenetic 16S rRNA pyrosequencing revealed that vacuum-packaged samples contained a higher total bacterial richness (n = 69 operational taxonomic units [OTUs]) than samples under the other packaging condition (n = 46 OTUs). The core community was composed of 6 OTUs (Lactobacillus sakei, Lactococcus piscium, Carnobacterium divergens, Carnobacterium maltaromaticum, Serratia proteamaculans, and Brochothrix thermosphacta), whereas 13 OTUs taxonomically assigned to the Enterobacteriaceae, Enterococcaceae, and Leuconostocaceae families comprised a less-abundant subpopulation. This subdominant community was significantly more abundant when 2.0% salt and vacuum packaging were used, and this correlated with a lower degree of spoilage. Our results demonstrate that salt reduction, particularly when it is combined with CO2-enriched packaging, promotes faster spoilage of raw sausages by lowering the overall bacterial diversity (both richness and evenness). IMPORTANCE Our study takes place in the context of raw meat product manufacturing and is linked to a requirement for salt reduction. Health guidelines are calling for a reduction in dietary salt intake. However, salt has been used for a very long time as a hurdle technology, and salt reduction in meat products raises the question of spoilage and waste of food. The study was conceived to assess the role of sodium chloride reduction in meat products, both at the level of spoilage development and at the level of bacterial diversity, using 16S rRNA amplicon sequencing and raw pork sausage as a meat model. PMID:27107120

Reducing Salt in Raw Pork Sausages Increases Spoilage and Correlates with Reduced Bacterial Diversity.

PubMed

Fougy, Lysiane; Desmonts, Marie-Hélène; Coeuret, Gwendoline; Fassel, Christine; Hamon, Erwann; Hézard, Bernard; Champomier-Vergès, Marie-Christine; Chaillou, Stéphane

2016-07-01

Raw sausages are perishable foodstuffs; reducing their salt content raises questions about a possible increased spoilage of these products. In this study, we evaluated the influence of salt reduction (from 2.0% to 1.5% [wt/wt]), in combination with two types of packaging (modified atmosphere [50% mix of CO2-N2] and vacuum packaging), on the onset of spoilage and on the diversity of spoilage-associated bacteria. After 21 days of storage at 8°C, spoilage was easily observed, characterized by noticeable graying of the products and the production of gas and off-odors defined as rancid, sulfurous, or sour. At least one of these types of spoilage occurred in each sample, and the global spoilage intensity was more pronounced in samples stored under modified atmosphere than under vacuum packaging and in samples with the lower salt content. Metagenetic 16S rRNA pyrosequencing revealed that vacuum-packaged samples contained a higher total bacterial richness (n = 69 operational taxonomic units [OTUs]) than samples under the other packaging condition (n = 46 OTUs). The core community was composed of 6 OTUs (Lactobacillus sakei, Lactococcus piscium, Carnobacterium divergens, Carnobacterium maltaromaticum, Serratia proteamaculans, and Brochothrix thermosphacta), whereas 13 OTUs taxonomically assigned to the Enterobacteriaceae, Enterococcaceae, and Leuconostocaceae families comprised a less-abundant subpopulation. This subdominant community was significantly more abundant when 2.0% salt and vacuum packaging were used, and this correlated with a lower degree of spoilage. Our results demonstrate that salt reduction, particularly when it is combined with CO2-enriched packaging, promotes faster spoilage of raw sausages by lowering the overall bacterial diversity (both richness and evenness). Our study takes place in the context of raw meat product manufacturing and is linked to a requirement for salt reduction. Health guidelines are calling for a reduction in dietary salt intake. However, salt has been used for a very long time as a hurdle technology, and salt reduction in meat products raises the question of spoilage and waste of food. The study was conceived to assess the role of sodium chloride reduction in meat products, both at the level of spoilage development and at the level of bacterial diversity, using 16S rRNA amplicon sequencing and raw pork sausage as a meat model. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Effect of packaging technology on microbiological and sensory quality of a cooked blood sausage, Morcela de Arroz, from Monchique region of Portugal.

PubMed

Pereira, J A; Dionísio, L; Patarata, L; Matos, T J S

2015-03-01

Morcela de Arroz (MA), a popular Portuguese blood sausage, with high pH and water activity (aw), is traditionally commercialized without preservatives and unpacked. This study evaluated the best packaging solution to extend MA shelf life stored at 4±1°C for 44days: without packaging (WP), vacuum (VP) and modified atmosphere packaging (MAP) (80% CO2; 20% N2). Mesophilic (MTVC), psychrotrophic (PTVC), lactic acid bacteria (LAB), pseudomonads, molds and yeasts, Enterobacteriaceae, Listeria monocytogenes, Salmonella spp., Bacillus cereus, Clostridium perfringens, sensory properties, pH, moisture and aw were studied. Moisture and aw decreased (p<0.05) in WP. pH decreased in WP and MAP during storage. MTVC and PTVC counts increased to values around 7logCFU/g at 44days of storage. LAB and Enterobacteriaceae counts were higher (p<0.05) in VP. Pseudomonads were inhibited (p<0.05) by MAP after 8days of storage. Sensory parameters were affected (p<0.05) by packaging and storage time. Globally, MAP performed better. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of Lemongrass Essential Oil Vapors on Microbial Dynamics and Listeria monocytogenes Survival on Rocket and Melon Stored under Different Packaging Conditions and Temperatures.

PubMed

Hadjilouka, Agni; Polychronopoulou, Melissanthi; Paramithiotis, Spiros; Tzamalis, Periklis; Drosinos, Eleftherios H

2015-09-09

The aim of the present study was to examine the effect of lemongrass essential oil vapors on the dynamics of surface microbiota and L. monocytogenes growth on rocket and melon under different packaging conditions and storage temperature. For that purpose, rocket and melon were placed on Expanded Polystyrene (EPS) trays, sprayed with L. monocytogenes to a population of 4.5-5.0 log CFU·g(-1), packaged using microperforated Oriented Polypropylene (OPP) film in either air or Microperforated Active Modified Atmosphere (MAMA) (initial atmosphere 5% O₂, 10% CO₂) including a Whatman paper containing the essential oil, without contact with the product, and stored at 0, 5, 10, and 15 °C. Application of lemongrass exhibited a bactericidal effect on enterococci and a fungistatic effect on yeast-mould populations but only during air storage of rocket. The former took place at all temperatures and the latter only at 10 and 15 °C. No effect on shelf life of both products was recorded. However, an important effect on the sensorial properties was observed; during the first 4-5 days of storage both products were organoleptically unacceptable. Regarding MAMA packaging, it affected only Pseudomonas spp. population resulting in a reduction of 1-2 log CFU·g(-1) in both products.

Effect of Lemongrass Essential Oil Vapors on Microbial Dynamics and Listeria monocytogenes Survival on Rocket and Melon Stored under Different Packaging Conditions and Temperatures

PubMed Central

Hadjilouka, Agni; Polychronopoulou, Melissanthi; Paramithiotis, Spiros; Tzamalis, Periklis; Drosinos, Eleftherios H.

2015-01-01

The aim of the present study was to examine the effect of lemongrass essential oil vapors on the dynamics of surface microbiota and L. monocytogenes growth on rocket and melon under different packaging conditions and storage temperature. For that purpose, rocket and melon were placed on Expanded Polystyrene (EPS) trays, sprayed with L. monocytogenes to a population of 4.5–5.0 log CFU·g−1, packaged using microperforated Oriented Polypropylene (OPP) film in either air or Microperforated Active Modified Atmosphere (MAMA) (initial atmosphere 5% O2, 10% CO2) including a Whatman paper containing the essential oil, without contact with the product, and stored at 0, 5, 10, and 15 °C. Application of lemongrass exhibited a bactericidal effect on enterococci and a fungistatic effect on yeast-mould populations but only during air storage of rocket. The former took place at all temperatures and the latter only at 10 and 15 °C. No effect on shelf life of both products was recorded. However, an important effect on the sensorial properties was observed; during the first 4–5 days of storage both products were organoleptically unacceptable. Regarding MAMA packaging, it affected only Pseudomonas spp. population resulting in a reduction of 1–2 log CFU·g−1 in both products. PMID:27682104

Effects of hydrogen peroxide, modified atmosphere and their combination on quality of minimally processed cluster beans.

PubMed

Waghmare, Roji B; Annapure, Uday S

2017-10-01

The aim of this study was to determine the potential of hydrogen peroxide (H 2 O 2 ) and modified atmosphere packaging (MAP) on quality of fresh-cut cluster beans. Fresh-cut cluster beans were dipped in a solution of 2% H 2 O 2 for 2 min, packed in an atmosphere of (5% O 2 , 10% CO 2 , 85% N 2 ) and stored in polypropylene bags at 5 °C for 35 days. Passive MAP was created by consuming O 2 and producing CO 2 by fresh-cut cluster beans. The combined effect of H 2 O 2 and MAP on physico-chemical analysis (Headspace gas, weight loss, chlorophyll, hardness and color), microbial quality (mesophilic aerobics and yeasts and molds) and sensory analysis were studied. Chemical treatment and MAP both are equally effective in extending the shelf life at 5 °C for 28 days. Hence, MAP can be an alternative for chemical treatment to achieve a shelf life of 28 days for fresh-cut cluster beans. Control samples, without chemical treatment and modified atmosphere, stored at 5 °C were spoiled after 14 days. Chemical treatment followed by MAP underwent minimum changes in weight, chlorophyll, hardness and color of fresh-cut cluster beans. Combination treatment gives a storage life of 35 days.

Effect of modified atmosphere packaging on the course of physical and chemical changes in chilled muscle tissue of silver carp (Hypophthalmichthys molitrix, V.).

PubMed

Jezek, F; Buchtová, H

2012-01-01

The effect of two types of modified atmosphere (MA1: 69% N2, 25% CO2, 5% O2, 1% CO; MA2: 70% N2, 30% CO2) on changes in physical and chemical parameters (pH, a(w)--water activity, TVBN - total volatile basic nitrogen, TMA - trimethylamine, FFA - free fatty acids, PV - peroxide value, TBA--thiobarbituric acid) in muscle tissues of the silver carp was monitored in the study. The samples were stored at temperatures +2 +/- 2 degrees C for 18 days. Changes in gas volumes (CO2 and O2) in MAs were also monitored. CO2 levels increased in MA1 but decreased in MA2. At the end of 18 days of storage, a significantly (P < 0.01) lower water activity (a(w)) levels were found in samples packaged under MA1, in contrast to samples packaged under MA2 where water activity values showed considerable fluctuation. Variations in pH values in the two types of MA showed similar trends. Sample pH gradually decreased until day 9 of storage. On day 11, muscle tissue pH increased markedly and then began to decrease again. The overall decrease in pH values was more profound in samples packaged under MA1. TVBN and TMA levels in samples packaged under the two types of MAs remained almost identical until day 9 of the experiment. Later, however, significantly (P < 0.01) higher levels of both parameters were found in muscle tissues packaged under MA1. FFA concentrations in silver carp samples in MA1 were significantly lower (P < 0.01) throughout the experiment. The PV increased significantly in both muscle samples tested. Greater fluctuations in this parameter's values throughout the experiment were observed in samples packaged under MA2. Faster rates of oxidation (P < 0.01) were found in samples packaged under MA1 starting on day 9. Maximum TBA values in MA1 and MA2 were observed on days 14 and 18 of the experiment, respectively. From the course of proteolytic and oxidative changes point of view, the more appropriate combination of gases for silver carp storage seems to be the mixture of 70% N2 and 30% CO2 (MA2), which allows for muscle storage of up to 9 days. We recommend TVBN as a suitable indicator of freshness, and TBA assay as a suitable indicator of the extent of oxidative processes.

Meteorological Instruction Software

NASA Technical Reports Server (NTRS)

1990-01-01

At Florida State University and the Naval Postgraduate School, meteorology students have the opportunity to apply theoretical studies to current weather phenomena, even prepare forecasts and see how their predictions stand up utilizing GEMPAK. GEMPAK can display data quickly in both conventional and non-traditional ways, allowing students to view multiple perspectives of the complex three-dimensional atmospheric structure. With GEMPAK, mathematical equations come alive as students do homework and laboratory assignments on the weather events happening around them. Since GEMPAK provides data on a 'today' basis, each homework assignment is new. At the Naval Postgraduate School, students are now using electronically-managed environmental data in the classroom. The School's Departments of Meteorology and Oceanography have developed the Interactive Digital Environment Analysis (IDEA) Laboratory. GEMPAK is the IDEA Lab's general purpose display package; the IDEA image processing package is a modified version of NASA's Device Management System. Bringing the graphic and image processing packages together is NASA's product, the Transportable Application Executive (TAE).

An Assessment of the Influence of the Industry Distribution Chain on the Oxygen Levels in Commercial Modified Atmosphere Packaged Cheddar Cheese Using Non-Destructive Oxygen Sensor Technology.

PubMed

O' Callaghan, Karen A M; Papkovsky, Dmitri B; Kerry, Joseph P

2016-06-20

The establishment and control of oxygen levels in packs of oxygen-sensitive food products such as cheese is imperative in order to maintain product quality over a determined shelf life. Oxygen sensors quantify oxygen concentrations within packaging using a reversible optical measurement process, and this non-destructive nature ensures the entire supply chain can be monitored and can assist in pinpointing negative issues pertaining to product packaging. This study was carried out in a commercial cheese packaging plant and involved the insertion of 768 sensors into 384 flow-wrapped cheese packs (two sensors per pack) that were flushed with 100% carbon dioxide prior to sealing. The cheese blocks were randomly assigned to two different storage groups to assess the effects of package quality, packaging process efficiency, and handling and distribution on package containment. Results demonstrated that oxygen levels increased in both experimental groups examined over the 30-day assessment period. The group subjected to a simulated industrial distribution route and handling procedures of commercial retailed cheese exhibited the highest level of oxygen detected on every day examined and experienced the highest rate of package failure. The study concluded that fluctuating storage conditions, product movement associated with distribution activities, and the possible presence of cheese-derived contaminants such as calcium lactate crystals were chief contributors to package failure.

An Assessment of the Influence of the Industry Distribution Chain on the Oxygen Levels in Commercial Modified Atmosphere Packaged Cheddar Cheese Using Non-Destructive Oxygen Sensor Technology

PubMed Central

O’ Callaghan, Karen A.M.; Papkovsky, Dmitri B.; Kerry, Joseph P.

2016-01-01

The establishment and control of oxygen levels in packs of oxygen-sensitive food products such as cheese is imperative in order to maintain product quality over a determined shelf life. Oxygen sensors quantify oxygen concentrations within packaging using a reversible optical measurement process, and this non-destructive nature ensures the entire supply chain can be monitored and can assist in pinpointing negative issues pertaining to product packaging. This study was carried out in a commercial cheese packaging plant and involved the insertion of 768 sensors into 384 flow-wrapped cheese packs (two sensors per pack) that were flushed with 100% carbon dioxide prior to sealing. The cheese blocks were randomly assigned to two different storage groups to assess the effects of package quality, packaging process efficiency, and handling and distribution on package containment. Results demonstrated that oxygen levels increased in both experimental groups examined over the 30-day assessment period. The group subjected to a simulated industrial distribution route and handling procedures of commercial retailed cheese exhibited the highest level of oxygen detected on every day examined and experienced the highest rate of package failure. The study concluded that fluctuating storage conditions, product movement associated with distribution activities, and the possible presence of cheese-derived contaminants such as calcium lactate crystals were chief contributors to package failure. PMID:27331815

Leuconostoc gasicomitatum is the dominating lactic acid bacterium in retail modified-atmosphere-packaged marinated broiler meat strips on sell-by-day.

PubMed

Susiluoto, Tuija; Korkeala, Hannu; Björkroth, K Johanna

2003-01-15

Lactic acid bacteria (LAB) in retail, modified-atmosphere-packaged (MAP), marinated broiler meat strips on sell-by-day were mainly identified as Leuconostoc gasicomitatum. A total of 32 packages, three to five packages of seven differently marinated broiler meat products, were studied at the end of the producer-defined shelf life (at 6 degrees C, 7-9 days depending on the manufacturer). Prior to the microbiological analyses, appearance and smell of the product was checked and pH measured. Bacteria were cultured on MRS and Tomato Juice Agar (TJA), Rogosa SL agar (SLA), Plate Count Agar (PCA) and Streptomycin Thallium Acetate Agar (STAA) for the enumeration of LAB, lactobacilli, total bacterial count and Brochothrix thermosphacta, respectively. The average CFU/g of the 32 packages was 2.3 x 10(8) on PCA. The highest bacterial average, 3.1 x 10(8), was recovered on TJA, the corresponding CFU/g averages on MRS and SLA being 2.3 x 10(8) and 1.3 x 10(8), respectively. Despite the high LAB numbers detected, radical spoilage changes such as unpleasant odor, slime production and formation of gas were not seen. B. thermosphacta did not form a significant part of the bacterial population since none of the levels exceeded the spoilage threshold level of 10(5) CFU/g reported in previous studies for this organism. In order to characterize the dominating LAB population, as many as 85, 85 and 88 colonies from MRS, TJA and SLA, respectively, were randomly picked and cultured pure. LAB were identified to species level using a 16 and 23S rDNA HindIiI RFLP (ribotyping) database. Fifty-six of the 170 isolates picked from the non-selective LAB media (MRS and TJA) were identified as L. gasicomitatum, followed by Carnobacterium divergens (41 isolates), Lactobacillus sakei and Lactobacillus curvatus subsp. melibiosus (31 isolates) and L. curvatus subsp. curvatus (20 isolates) species. SLA proved not to be completely selective for lactobacilli because the growth of Leuconostoc spp. was not inhibited, Carnobacterium spp. were the only species not detected on SLA.

Functions of Nano-Materials in Food Packaging

NASA Astrophysics Data System (ADS)

Yap, Ray Chin Chong; Kwablah, Amegadze Paul Seyram; He, Jiating; Li, Xu

Food packaging has been changing from bulky and rigid form in the past to different variation of lights and plastic packagings. Regardless of the changes, the packaging must be able to uphold its original function which is to serve as food containment as well as to protect the food from the external environment. Coupled with the increasing consumer’s awareness on food waste, higher standard of living, technological developments are underway to enhance the shelf-life of packed food as well as methods to provide indications of food packaging environment. There are many different indicators for food spoilage, but two commonly found gases in food packaging are oxygen and carbon dioxide. Oxygen is the main mechanism for food spoilage, while carbon dioxide is often used in modified-atmosphere-packaging. There are also different methods of gas scavenging and/or sensing techniques based on different concepts in the literature. In this review, the focus will be on nano-materials, namely titanium dioxide, silica, zeolites and metal organic frameworks. This review is structured in a manner to highlight how each material can be used in both gas scavenging and/or indicators applications. The last part of the review focuses on the approach and some key considerations when integrating nano-materials into the plastic film.

Optical sensors for application in intelligent food-packaging technology

NASA Astrophysics Data System (ADS)

McEvoy, Aisling K.; Von Bueltzingsloewen, Christoph; McDonagh, Colette M.; MacCraith, Brian D.; Klimant, Ingo; Wolfbeis, Otto S.

2003-03-01

Modified Atmosphere Packaged (MAP) food employs a protective gas mixture, which normally contains selected amounts of carbon dioxide (CO2) and oxygen (O2), in order to extend the shelf life of food. Conventional MAP analysis of package integrity involves destructive sampling of packages followed by carbon dioxide and oxygen detection. For quality control reasons, as well as to enhance food safety, the concept of optical on-pack sensors for monitoring the gas composition of the MAP package at different stages of the distribution process is very attractive. The objective of this work was to develop printable formulations of oxygen and carbon dioxide sensors for use in food packaging. Oxygen sensing is achieved by detecting the degree of quenching of a fluorescent ruthenium complex entrapped in a sol-gel matrix. In particular, a measurement technique based on the quenching of the fluorescence decay time, phase fluorometric detection, is employed. A scheme for detecting CO2 has been developed which is compatible with the oxygen detection scheme. It is fluorescence-based and uses the pH-sensitive 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS) indicator dye encapsulated in an organically modified silica (ORMOSIL) glass matrix. Dual Luminophore Referencing (DLR) has been employed as an internal referencing scheme, which provides many of the advantages of lifetime-based fluorometric methods. Oxygen cross-sensitivity was minimised by encapsulating the reference luminophore in dense sol-gel microspheres. The sensor performance compared well with standard methods for both oxygen and carbon dioxide detection. The results of preliminary on-pack print trials are presented and a preliminary design of an integrated dual gas optical read-out device is discussed.

Relation between microbiological quality, metabolite production and sensory quality of equilibrium modified atmosphere packaged fresh-cut produce.

PubMed

Jacxsens, L; Devlieghere, F; Ragaert, P; Vanneste, E; Debevere, J

2003-06-25

The quality of four types of fresh-cut produce, packaged in consumer-sized packages under an equilibrium modified atmosphere and stored at 7 degrees C, was assessed by establishing the relation between the microbial outgrowth and the corresponding production of nonvolatile compounds and related sensory disorders. In vitro experiments, performed on a lettuce-juice-agar, demonstrated the production of nonvolatile compounds by spoilage causing lactic acid bacteria and Enterobacteriaceae. Pseudomonas fluorescens and yeasts, however, were not able to produce detectable amounts of nonvolatile metabolites. The type of spoilage and quality deterioration in vivo depended on the type of vegetable. Mixed lettuce and chicory endives, leafy tissues, containing naturally low concentrations of sugars, showed a spoilage dominated by Gram-negative microorganisms, which are not producing nonvolatile compounds. Sensory problems were associated with visual properties and the metabolic activity of the plant tissue. Mixed bell peppers and grated celeriac, on the other hand, demonstrated a fast and intense growth of spoilage microorganisms, dominated by lactic acid bacteria and yeasts. This proliferation resulted in detectable levels of organic acids and the rejection by the trained sensory panel was based on the negative perception of the organoleptical properties (off-flavour, odour and taste). The applied microbiological criteria corresponded well with detectable changes in sensory properties and measurable concentrations of nonvolatile compounds, surely in the cases where lactic acid bacteria and yeasts were provoking spoilage. Consequently, the freshness of minimally processed vegetables, sensitive for outgrowth of lactic acid bacteria and yeasts (e.g., carrots, celeriac, bell peppers, mixtures with non-leafy vegetables) can be evaluated via analysis of the produced nonvolatile compounds.

Effects of natural antimicrobials with modified atmosphere packaging on the growth kinetics of Listeria monocytogenes in ravioli at various temperatures

PubMed Central

Ro, Eun Young; Kim, Geun Su; Kwon, Do Young; Park, Young Min; Cho, Sang Woo; Lee, Sang Yun; Yeo, Ik Hyun

2017-01-01

Abstract The objective of this study was to investigate the antimicrobial effects of cultured sugar/vinegar (CSV) blend and nisin to control the risk of Listeria monocytogenes in ready to cook (RTC) ravioli. Ravioli dough was prepared with 0.1, 0.3, 0.5, 1% CSV blend and 0.1, 0.2, and 0.3% nisin. Inoculated spinach or artichoke raviolis with 2.0 ± 0.5 log cfu/g of L. monocytogenes were packed aerobically or using modified atmosphere packaging (MAP), and then stored at 4, 10, 17, and 24 °C for 60 days. Growth kinetic parameters of the observed data fit well to the Baranyi equation. Ravioli with spinach filling materials yielded a higher risk than that with artichoke. L. monocytogenes was able to survive in ravioli with artichoke, but did not grow. The addition of 1% CSV blend or 0.3% nisin in spinach ravioli with the combination of MAP effectively controlled the growth of L. monocytogenes at the temperature below 10 °C. The organoleptic quality of spinach ravioli was not also affected by the application of 1% CSV blend. Therefore, the CSV blend can be recommended to improve the microbial safety and quality of natural RTC ravioli at retail market. Practical applications The risk of ravioli was affected by the filling materials of ravioli at retail market. Addition of 1% cultured sugar/vinegar blend in dough substantially contributes to the extension of shelf‐life of MAP spinach raviolis. classification and regression tree analysis results indicate that refrigeration temperature is the main control factor to affect lag time and growth rate, while packaging method is critical for maximum population density. PMID:29456276

Reduction of Salmonella on chicken breast fillets stored under aerobic or modified atmosphere packaging by the application of lytic bacteriophage preparation SalmoFreshTM.

PubMed

Sukumaran, Anuraj T; Nannapaneni, Rama; Kiess, Aaron; Sharma, Chander Shekhar

2016-03-01

The present study evaluated the efficacy of recently approved Salmonella lytic bacteriophage preparation (SalmoFresh™) in reducing Salmonella on chicken breast fillets, as a surface and dip application. The effectiveness of phage in combination with modified atmosphere packaging (MAP) and the ability of phage preparation in reducing Salmonella on chicken breast fillets at room temperature was also evaluated. Chicken breast fillets inoculated with a cocktail of Salmonella Typhimurium, S. Heidelberg, and S. Enteritidis were treated with bacteriophage (10(9) PFU/mL) as either a dip or surface treatment. The dip-treated samples were stored at 4°C aerobically and the surface-treated samples were stored under aerobic and MAP conditions (95% CO2/5% O2) at 4°C for 7 d. Immersion of Salmonella-inoculated chicken breast fillets in bacteriophage solution reduced Salmonella (P < 0.05) by 0.7 and 0.9 log CFU/g on d 0 and d 1 of storage, respectively. Surface treatment with phage significantly (P < 0.05) reduced Salmonella by 0.8, 0.8, and 1 log CFU/g on d 0, 1, and 7 of storage, respectively, under aerobic conditions. Higher reductions in Salmonella counts were achieved on chicken breast fillets when the samples were surface treated with phage and stored under MAP conditions. The Salmonella counts were reduced by 1.2, 1.1, and 1.2 log CFU/g on d 0, 1, and 7 of storage, respectively. Bacteriophage surface application on chicken breast fillets stored at room temperature reduced the Salmonella counts by 0.8, 0.9, and 0.4 log CFU/g after 0, 4, and 8 h, respectively, compared to the untreated positive control. These findings indicate that lytic phage preparation was effective in reducing Salmonella on chicken breast fillets stored under aerobic and modified atmosphere conditions. © 2015 Poultry Science Association Inc.

Effect of the dietary supplementation with Vitamin E on colour stability of packaged, sliced pasteurized ham.

PubMed

Houben, J H; Gerris, C V

1998-12-01

The effect of dietary supplementation with vitamin E (200IU kg(-1) feed) on the colour stability of pasteurized ham was studied. Pigs were fed on control and enriched diets for the last 12 weeks before slaughter. Pasteurized ham was manufactured from the hams from 6 barrows and 6 gilts per dietary group. Half of the samples of sliced ham from control and supplemented pigs were packaged under vacuum (VAC) and half in low-oxygen modified atmosphere packs (FOG, gas mixture: CO(2)/N(2)=60/40). Half the packages were kept under constant illumination and the other half in the dark, both for 22 days at 7°C. The redness component of the VAC-packaged ham prepared from vitamin E-supplemented pigs was slightly more stable than that of comparably packaged ham prepared from control pigs. The opposite was observed for the FOG-packaged products. Overall, colour changes were greater in the ham in FOG-packs than in the ham in VAC-packs. In addition, the colour of the FOG-packaged ham was clearly affected by illumination, whereas the colour of the VAC-packaged ham appeared more stable. It is concluded that dietary supplementation of pigs with vitamin E does not appear to offer significant advantages over currently used feeding regimens with regard to the quality of the ham produced.

Colour of ground beef as influenced by raw materials, addition of sodium chloride and low oxygen packaging.

PubMed

Sørheim, O; Westad, F; Larsen, H; Alvseike, O

2009-03-01

The study aimed at examining the effects of freezing of raw materials, holding time for fresh raw materials post mortem and addition of 0.5-1.0% NaCl on the colour of ground beef under low oxygen (O2) modified atmosphere storage. The samples were exposed to 0.1-3.0% O2 at 4°C for up to 10 days, and analysed for O2 concentrations, instrumental and visual colour. Residual O2 in the headspace of the packages oxidizes myoglobin and discolours the meat. Meat may have the ability to scavenge residual O2, and ground beef differs from intact muscles by having a much higher capacity for O2 consumption. In this experiment, the use of frozen/thawed raw materials and addition of NaCl both decreased the rate of O2 consumption and increased discolouration. Using raw materials from 2 days rather than 7 days post mortem greatly increased the rate of removal of O2 and improved redness. In low O2 packaging, ground beef preferably should be stored for at least 2 days in an atmosphere with less than 0.1% residual O2 to produce a purple pigment predominantly consisting of deoxymyoglobin.

Food losses, shelf life extension and environmental impact of a packaged cheesecake: A life cycle assessment.

PubMed

Gutierrez, Michele Mario; Meleddu, Marta; Piga, Antonio

2017-01-01

Packaging is associated with a high environmental impact. This is also the case in the food industry despite packaging being necessary for maintaining food quality, safety assurance and preventing food waste. The aim of the present study was to identify improvements in food packaging solutions able to minimize environmental externalities while maximizing the economic sustainability. To this end, the life cycle assessment (LCA) methodology was applied to evaluate the environmental performance of new packaging solutions. The environmental impact of packaging and food losses and the balance between the two were examined in relation to a cheesecake that is normally packaged in low density polyethylene film and has a limited shelf life due to microbial growth. A shelf life extension was sought via application of the well-established modified atmosphere packaging (MAP) technique. Samples for MAP (N 2 /CO 2 : 70/30) were placed inside multilayer gas barrier trays, which were then wrapped with a multilayer gas and water barrier film (i.e. AerPack packaging); control batches were packaged in gas barrier recycled polyethylene terephthalate (XrPet) trays and wrapped with a XrPet film. Samples were then stored at 20°C and inspected at regular intervals for chemical-physical, microbiological and sensory parameters. Results show that the new packaging solution could considerably extend the shelf life of cheesecakes, thereby reducing food waste and decreasing the overall environmental impact. Moreover, the new packaging allows one to minimize transport costs and to generate economies of scale in manufacturing. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modified-atmosphere storage under subatmospheric pressure and beef quality: II. Color, drip, cooking loss, sarcomere length, and tenderness.

PubMed

Smulders, F J M; Hiesberger, J; Hofbauer, P; Dögl, B; Dransfield, E

2006-09-01

Beef has a requirement for refrigerated storage up to 14 d to achieve adequate aging and a tender product. To achieve this aging with little spoilage and no surface drying, vacuum packaging is attractive, because it is inherently simple and offers a clear indication to the packer when the process has failed or there is risk of spoilage. However, there is increasing pressure on the meat industry to limit the use of packaging materials in view of their cost and the cost involved in their recovery and recycling. The purpose of this report was to evaluate an alternative storage system in containers using modified atmospheres at reduced pressure (approximately 25 kPa). The quality of the meat for both container- and vacuum-packed treatments was measured during chilled storage for up to 3 wk. Storage time had the most significant effect on quality characteristics, irrespective of the packaging method. Storage in containers under a 70%N2:30%CO2 gas mixture gave characteristics similar to beef stored under vacuum. Storage in containers under 100% CO2 produced less drip loss than under 70%N2:30%CO2, but generally container storage produced 3 times as much drip loss as vacuum packaging. Shear force of the LM was unaffected by the type of packaging, and at d 2 after slaughter (i.e., before the storage trial was begun), sarcomere lengths of muscles intended for container storage were similar to those destined for vacuum storage. During the packaging treatment, the comparison between the storage systems was always done within 1 animal using one carcass-half for container storage and the other half for vacuum packaging; all bulls were shackled from the left hindleg during bleeding. The majority of the muscles from the left sides had lower shear force values than those from the right sides at the earlier storage times (2 and 9 d after slaughter) but had similar values after longer storage (16 and 23 d after slaughter). This is the first report that shackling beef carcasses from the left side can result in more tender meat in the LM from that side. The increased tenderness in the LM from the shackled side probably resulted from an early decrease in pH and an increase in calpain activity after mechanical strain of the muscles on the shackled side. This effect of shackling should be taken into account when designing systematic comparisons of tenderness in beef.

Optimisation of colour stability of cured ham during packaging and retail display by a multifactorial design.

PubMed

Møller, Jens K S; Jakobsen, Marianne; Weber, Claus J; Martinussen, Torben; Skibsted, Leif H; Bertelsen, Grete

2003-02-01

A multifactorial design, including (1) percent residual oxygen, (2) oxygen transmission rate of packaging film (OTR), (3) product to headspace volume ratio, (4) illuminance level and (5) nitrite level during curing, was established to investigate factors affecting light-induced oxidative discoloration of cured ham (packaged in modified atmosphere of 20% carbon dioxide and balanced with nitrogen) during 14 days of chill storage. Univariate statistical analysis found significant effects of all main factors on the redness (tristimulus a-value) of the ham. Subsequently, Response Surface Modelling of the data further proved that the interactions between packaging and storage conditions are important when optimising colour stability. The measured content of oxygen in the headspace was incorporated in the model and the interaction between measured oxygen content in the headspace and the product to headspace volume ratio was found to be crucial. Thus, it is not enough to keep the headspace oxygen level low, if the headspace volume at the same time is large, there will still be sufficient oxygen for colour deteriorating processes to take place.

Active package for wild strawberry fruit (Fragaria vesca L.).

PubMed

Almenar, Eva; Del Valle, Valeria; Catala, Ramón; Gavara, Rafael

2007-03-21

An antimicrobial active package has been developed to improve the safety and quality of wild strawberries, as well as extending their shelf life. The fruits were packed in equilibrium-modified atmosphere packaging (EMAP), and the effect on Botrytis cinerea growth and on the quality parameters of the fruit by the addition of different amounts of 2-nonanone, an antifungal volatile compound naturally present in strawberries, was investigated during storage at 10 and 22 degrees C. The temperature of 10 degrees C was chosen as the temperature used at points of sale, and 22 degrees C was chosen as the control temperature. Fungal growth was inhibited in all cases, possibly due to the synergistic effect of high CO2 partial pressures and the presence of the antifungal compound. Weight, soluble solids, titrable acidity, and anthocyanin losses were retarded by the presence of 2-nonanone. This effect was more pronounced as the 2-nonanone concentration was increased at both temperatures. Therefore, an active package that releases 2-nonanone inhibits fungal decay and delays the senescence of highly perishable wild strawberry fruit.

Lipid oxidation and color changes of goose meat stored under vacuum and modified atmosphere conditions.

PubMed

Orkusz, A; Haraf, G; Okruszek, A; Werenska-Sudnik, M

2017-03-01

The objective of the work was to investigate the color and lipid oxidation changes of goose breast meat packaged in vacuum and modified atmosphere (MA) conditions consisting of 80% O2, 20% CO2, and stored in refrigerated conditions at 4°C. Color stability was monitored by determining total heme pigments concentration; relative concentration of myoglobin, oxymyoglobin, and metmyoglobin; parameters of color L*, a*, b*, and sensory evaluation of the surface color. Lipid stability was measured by determining thiobarbituric acid reactive substances (TBARS). The samples were examined in 24 h after slaughter (unpacked muscles) and on d 4, 7, 9, 11 of storage (muscles packed in vacuum and in MA). Through the time of storage, samples packed in MA had higher TBARS values in comparison to the meat packed in vacuum. For samples packed in two types of atmospheres, the total pigments concentration decreased gradually within 11 d of storage. It was observed that relative metmyoglobin concentration increased whereas relative oxymyoglobin concentration decreased in total heme pigments in the MA stored muscle. The relative concentration of all three myoglobin forms sample packed in vacuum remained unchanged. The color parameters (L*, a*, b*) did not change for 11 d of storage for the vacuum packed meat. The value of the color parameter a* decreased and the value of the color parameters L* and b* increased in the samples packaged in MA. The data prove that if you store goose meat in MA (consisting of 80% O2, 20% CO2) or vacuum, the unchanged surface color is preserved for 9 and 11 day, respectively.Vacuum appears to be a better method as regards the maintaining of lipid stability in goose meat. © 2016 Poultry Science Association Inc.

Influence of PA6 nanocomposite films on the stability of vacuum-aged beef loins during storage in modified atmospheres.

PubMed

Picouet, P A; Fernandez, A; Realini, C E; Lloret, E

2014-01-01

A masterbatch of polyamide 6 (PA6) containing dispersed nanoclays, was used to fabricate a novel multilayer film for vacuum packed meat. Performance of the nanocomposite was compared to a control PA6 multilayer and a high barrier commercial film. Addition of nanoclays improved oxygen barrier properties, UV-blocking capability and stiffness. Beef loins were vacuum-aged using the three films for 0 7, 14 and 21 days at 2°C. After each ageing time, beef steaks were packaged in commercial trays and high oxygen atmosphere and stored at 4°C for 9 days. Beef quality parameters and gas content were studied during display time in MAP (1, 3, 6 and 9 d). Beef quality parameters were not influenced by the packaging materials used during ageing and the performance of nanocomposites was comparable to high barrier films. Ageing had a positive impact on the stabilization of redness up to day 6 in MAP. Thereafter, oxymyoglobin content and oxidation levels were negatively influenced by ageing. © 2013.

Bayesian Atmospheric Radiative Transfer (BART): Model, Statistics Driver, and Application to HD 209458b

NASA Astrophysics Data System (ADS)

Cubillos, Patricio; Harrington, Joseph; Blecic, Jasmina; Stemm, Madison M.; Lust, Nate B.; Foster, Andrew S.; Rojo, Patricio M.; Loredo, Thomas J.

2014-11-01

Multi-wavelength secondary-eclipse and transit depths probe the thermo-chemical properties of exoplanets. In recent years, several research groups have developed retrieval codes to analyze the existing data and study the prospects of future facilities. However, the scientific community has limited access to these packages. Here we premiere the open-source Bayesian Atmospheric Radiative Transfer (BART) code. We discuss the key aspects of the radiative-transfer algorithm and the statistical package. The radiation code includes line databases for all HITRAN molecules, high-temperature H2O, TiO, and VO, and includes a preprocessor for adding additional line databases without recompiling the radiation code. Collision-induced absorption lines are available for H2-H2 and H2-He. The parameterized thermal and molecular abundance profiles can be modified arbitrarily without recompilation. The generated spectra are integrated over arbitrary bandpasses for comparison to data. BART's statistical package, Multi-core Markov-chain Monte Carlo (MC3), is a general-purpose MCMC module. MC3 implements the Differental-evolution Markov-chain Monte Carlo algorithm (ter Braak 2006, 2009). MC3 converges 20-400 times faster than the usual Metropolis-Hastings MCMC algorithm, and in addition uses the Message Passing Interface (MPI) to parallelize the MCMC chains. We apply the BART retrieval code to the HD 209458b data set to estimate the planet's temperature profile and molecular abundances. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. JB holds a NASA Earth and Space Science Fellowship.

Quality of fresh-cut baby spinach grown under a floating trays system as affected by nitrogen fertilisation and innovative packaging treatments.

PubMed

Rodríguez-Hidalgo, Stephanie; Artés-Hernández, Francisco; Gómez, Perla A; Fernández, Juan Antonio; Artés, Francisco

2010-04-30

Alternative techniques for cultivation of leafy vegetables such as a floating tray system and unconventional gas mixtures for post-harvest active modified atmosphere packaging (MAP) could be of interest in the minimally processed vegetable industry. The combined effect of three pre-harvest fertilisation doses (8, 12 or 16 mmol N L(-1)) and three post-harvest MAP conditions (passive, super-atmospheric or N2O-enriched) on the main quality attributes of fresh-cut baby spinach leaves throughout 10 days at 5 degrees C was studied. After 8 days of shelf life, spinach leaves fertilised with 8 and 16 mmol N L(-1) and stored under N2O-enriched MAP showed the lowest microbial growth, with good sensory quality. Such combined treatments also preserved the total antioxidant capacity sampled at harvest (8 g ascorbic acid equivalent antioxidant capacity kg(-1) f.w.). A decrease of 10-20% in total vitamin C content regardless of N fertilisation and packaging treatment was found during shelf life. Total phenolics content at harvest was 2 g gallic acid equivalents kg(-1) f.w., which was slightly decreased or preserved during shelf life while total chlorophylls were preserved for all treatments assayed around 550 mg kg(-1) f.w. No clear effect of fertilisation doses was observed during post-harvest storage on overall quality of fresh-cut baby spinach leaves, while N2O-enriched atmospheres seems to be a promising alternative to passive MAP for extending shelf life.

Combined effect of starch/montmorillonite coating and passive MAP in antioxidant activity, total phenolics, organic acids and volatile of fresh-cut carrots.

PubMed

Guimarães, Isabela Costa; dos Reis, Kelen Cristina; Menezes, Evandro Galvão Tavares; Borges, Paulo Rogério Siriano; Rodrigues, Ariel Costa; Leal, Renato; Hernandes, Thais; de Carvalho, Elisângela Helena Nunes; Vilas Boas, Eduardo Valério de Barros

2016-01-01

This work evaluates fresh-cut carrots (FCC) coated with montmorillonite (MMT) subjected to passive modified atmosphere packaging. Carrots were sanitized, cooled, peeled and sliced. Half of the FCC were coated with MMT nanoparticle film and the other half were not. All FCCs were packed in a polypropylene rigid tray, covered with a polypropylene rigid lid or sealed with polyethylene + propylene film, in four treatments (RL, rigid lid; RLC, rigid lid + coating; ST, sealed tray; STC, sealed tray + coating). FCCs were stored at 4 °C and were analyzed weekly for 4 weeks (total antioxidant activity by 2,2-diphenyl-1-picryl hydrazyl method and the β-carotene/linoleic acid, phenolic compounds, organic acids and volatile compounds). The use of coating film with starch nanoparticles and a modified atmosphere leads to the preservation of the total antioxidant activity, the volatile and organic acids of FCC.

Characterisation of volatile profile and sensory analysis of fresh-cut "Radicchio di Chioggia" stored in air or modified atmosphere.

PubMed

Cozzolino, Rosaria; Martignetti, Antonella; Pellicano, Mario Paolo; Stocchero, Matteo; Cefola, Maria; Pace, Bernardo; De Giulio, Beatrice

2016-02-01

The volatile profile of two hybrids of "Radicchio di Chioggia", Corelli and Botticelli, stored in air or passive modified atmosphere (MAP) during 12 days of cold storage, was monitored by solid phase micro-extraction (SPME) GC-MS. Botticelli samples were also subjected to sensory analysis. Totally, 61 volatile organic compounds (VOCs) were identified in the headspace of radicchio samples. Principal component analysis (PCA) showed that fresh product possessed a metabolic content similar to that of the MAP samples after 5 and 8 days of storage. Projection to latent structures by partial least squares (PLS) regression analysis showed the volatiles content of the samples varied depending only on the packaging conditions. Specifically, 12 metabolites describing the time evolution and explaining the effects of the different storage conditions were highlighted. Finally, a PCA analysis revealed that VOCs profile significantly correlated with sensory attributes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Zeppelin NT - Measurement Platform for the Exploration of Atmospheric Chemistry and Dynamics in the Planetary Boundary Layer

NASA Astrophysics Data System (ADS)

Hofzumahaus, Andreas; Holland, Frank; Oebel, Andreas; Rohrer, Franz; Mentel, Thomas; Kiendler-Scharr, Astrid; Wahner, Andreas; Brauchle, Artur; Steinlein, Klaus; Gritzbach, Robert

2014-05-01

The planetary boundary layer (PBL) is the chemically most active and complex part of the atmosphere where freshly emitted reactive trace gases, tropospheric radicals, atmospheric oxidation products and aerosols exhibit a large variability and spatial gradients. In order to investigate the chemical degradation of trace gases and the formation of secondary pollutants in the PBL, a commercial Zeppelin NT was modified to be used as an airborne measurement platform for chemical and physical observations with high spatial resolution. The Zeppelin NT was developed by Zeppelin Luftschifftechnik (ZLT) and is operated by Deutsche Zeppelin Reederei (DZR) in Friedrichshafen, Germany. The modification was performed in cooperation between Forschungszentrum Jülich and ZLT. The airship has a length of 75 m, can lift about 1 ton of scientific payload and can be manoeuvered with high precision by propeller engines. The modified Zeppelin can carry measurement instruments mounted on a platform on top of the Zeppelin, or inside the gondola beneath the airship. Three different instrument packages were developed to investigate a. gas-phase oxidation processes involving free radicals (OH, HO2) b. formation of secondary organic aerosols (SOA) c. new particle formation (nucleation) The presentation will describe the modified airship and provide an overview of its technical performance. Examples of its application during the recent PEGASOS flight campaigns in Europe will be given.

Chemical and optical characterization of white efflorescences on dry fermented sausages under modified atmosphere packaging.

PubMed

Walz, Felix H; Gibis, Monika; Herrmann, Kurt; Hinrichs, Jörg; Weiss, Jochen

2017-11-01

Dry fermented sausages that are packed under modified atmosphere are often affected by the formation of white crystals on the surface. These so called efflorescences are rejected by consumers and lead to high financial losses for the meat processing industry. In this study, the distribution of efflorescence-causing components was investigated over the sausage profile during 8 weeks of storage under modified atmosphere at 4 °C. In addition, two visual methods (image and sensory analyses) were compared regarding the ability to quantify the efflorescence content. The initial formation of efflorescences was observed after 2 weeks (7%). After 4 weeks of storage, 23.4% of the sausage surface was covered with efflorescences, and the amount of efflorescences did not change significantly by the end of storage. Furthermore, chemical analyses revealed that magnesium (increased by 98.1%), lactate (increased by 54.2%) and creatine (increased by 51.8%) are enriched on the sausage surface during storage. Sensory and image analyses lead to comparable results (r = 0.992) and therefore both are suitable to quantify the amount of efflorescences. The moisture gradient in the interior of the sausages which is built upon drying is supposed to be the driving force for the movement of efflorescence-causing compounds. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Modeling microbial spoilage and quality of gilthead seabream fillets: combined effect of osmotic pretreatment, modified atmosphere packaging, and nisin on shelf life.

PubMed

Tsironi, Theofania N; Taoukis, Petros S

2010-05-01

The objective of the study was the kinetic modeling of the effect of storage temperature on the quality and shelf life of chilled fish, modified atmosphere-packed (MAP), and osmotically pretreated with the addition of nisin as antimicrobial agent. Fresh gilthead seabream (Sparus aurata) fillets were osmotically treated with 50% high dextrose equivalent maltodextrin (DE 47) plus 5% NaCl. Water loss, solid gain, salt content, and water activity were monitored throughout treatment and treatment conditions were selected for the shelf life study. Untreated and osmotically pretreated slices with and without nisin (2 x 10(4) IU/100 g osmotic solution), packed in air or modified atmosphere (50% CO(2)-50% air), and stored at controlled isothermal conditions (0, 5, 10, and 15 degrees C) were studied. Quality assessment and modeling were based on growth of several microbial indices, total volatile nitrogen, trimethylamine nitrogen, lipid oxidation (TBARS), and sensory scoring. Temperature dependence of quality loss rates was modeled by the Arrhenius equation, validated under dynamic conditions. Pretreated samples showed improved quality stability during subsequent refrigerated storage, in terms of microbial growth, chemical changes, and organoleptic degradation. Osmotic pretreatment with the addition of nisin in combination with MAP was the most effective treatment resulting in significant shelf life extension of gilthead seabream fillets (48 days compared to 10 days for the control at 0 degrees C).

Performance of Poly(lactic acid) Surface Modified Films for Food Packaging Application

PubMed Central

Dalla Rosa, Marco; Iordanskii, Alexey L.

2017-01-01

Five Poly(lactic acid) (PLA) film samples were analyzed to study the gas barrier behavior, thermal stability and mechanical performance for food packaging application. O2, CO2, N2, N2O, and C2H4 pure gases; Air; and Modified Atmosphere (MA, 79% N2O/21% O2) were used to analyze the influence of the chemical structure, storage temperature and crystalline phase on the gas barrier behavior. The kinetic of the permeation process was investigated at different temperatures, ranging from 5 °C to 40 °C. Annealing thermal treatment on the samples led to the crystalline percentage, influencing especially the gas solubility process. Thermal properties such as Tg and χc, and mechanical properties such as tensile strength and modulus were remarkably improved with surface PLA modification. A more pronounced reinforcing effect was noted in the case of metallization, as well as improved gas barrier performance. Tensile testing and tensile cycling tests confirmed the rigidity of the films, with about a 20% loss of elasticity after 25 cycles loading. PMID:28773210

Opportunities for bio-based packaging technologies to improve the quality and safety of fresh and further processed muscle foods.

PubMed

Cutter, Catherine Nettles

2006-09-01

It has been well documented that vacuum or modified atmosphere packaging materials, made from polyethylene- or other plastic-based materials, have been found to improve the stability and safety of raw or further processed muscle foods. However, recent research developments have demonstrated the feasibility, utilization, and commercial application of a variety of bio-based polymers or bio-polymers made from a variety of materials, including renewable/sustainable agricultural commodities, and applied to muscle foods. A variety of these bio-based materials have been shown to prevent moisture loss, drip, reduce lipid oxidation and improve flavor attributes, as well as enhancing the handling properties, color retention, and microbial stability of foods. With consumers demanding more environmentally friendly packaging and a desire for more natural products, bio-based films or bio-polymers will continue to play an important role in the food industry by improving the quality of many products, including fresh or further processed muscle foods.

Thyme oil vapour and modified atmosphere packaging reduce anthracnose incidence and maintain fruit quality in avocado.

PubMed

Sellamuthu, Periyar Selvam; Mafune, Mpho; Sivakumar, Dharini; Soundy, Puffy

2013-09-01

Postharvest application of prochloraz fungicide is commercially practiced to control anthracnose, a postharvest disease in avocado. Increasing consumer concern regarding food safety and demand for organically produced fruits make it necessary to search for natural environmentally friendly alternative products and processes for the fruit industry. A combination of modified atmosphere packaging (MAP; ∼8% CO₂, 2% O₂) plus thyme oil (TO) was evaluated on the incidence and severity of anthracnose, physiological disorders (grey pulp, vascular browning), fruit quality parameters (L*, h°, firmness, weight loss) and sensory parameters (taste, texture, flavour and overall acceptance), phenylalanine ammonia-lyase (PAL) enzyme activity, total phenolic compounds, flavonoid contents and antioxidant activity in avocados ('Fuerte' and 'Hass' cultivars) held at 10 °C cold storage for 18 days and thereafter, ripened at 25 °C for 5-10 days. Stand-alone MAP, commercial treatment (prochloraz 0.05%) and untreated (control) fruit were included for comparison. MAP + TO treatment significantly (P < 0.05) reduced the incidence and severity of anthracnose, grey pulp, vascular browning, weight loss and loss of fruit firmness, and showed acceptable taste, flavour, texture and higher overall acceptance, increased PAL activity, total phenolic compounds, flavonoid contents and antioxidant activity, after ripening at 25 °C followed by cold storage at 10 °C. This investigation recommends MAP + TO combination treatment as a suitable alternative to the currently adopted prochloraz application. © 2013 Society of Chemical Industry.

Influence of Barley Sourdough and Vacuum Cooling on Shelf Life Quality of Partially Baked Bread

PubMed Central

2017-01-01

Summary Driven by the bakery industry urge to satisfy consumer demand for fresh, diverse and high quality bakery products, we investigated the influence of barley sourdough and vacuum cooling on shelf life quality of partially baked bread stored in modified atmosphere packaging at ambient conditions. Barley sourdough was fermented with Lactobacillus reuteri (DSM 20016, F275). Partially baked bread with sourdough was microbiologically acceptable during 30 days of storage, while bread without sourdough had detectable mould on the 30th day. Stored bread samples were rebaked after 1, 8, 15, 22 and 30 days to determine moisture content, physical and sensorial properties. Moisture loss (5%) was detected on the 15th day, after which it remained stable until the end of investigated storage period. Nevertheless, textural quality of stored bread continuously declined due to crumb firming. Bread flavour did not change during mould-free storage time. The principal component analysis identified major differences in the flavour of sour and control bread, also in crumb firmness and moisture content of samples. This study indicates the positive role of barley sourdough fermented with L. reuteri in improving crumb texture for at least 15 days, and ensuring mould- and bacteria-free partially baked bread for 30 days. Vacuum cooling combined with sourdough improved bread shape, porosity, and reduced sour taste, crust colouring and crumbliness. Hence, it can successfully extend shelf life quality of partially baked bread in modified atmosphere packaging. PMID:29540981

Radiation resistance and loss of crystal violet binding activity in Yersinia enterocolitica suspended in raw ground pork exposed to gamma radiation and modified atmosphere.

PubMed

Bhaduri, Saumya; Sheen, Shiowshuh; Sommers, Christopher H

2014-05-01

Virulence of many foodborne pathogens is directly linked to genes carried on self-replicating extra-chromosomal elements, which can transfer genetic material, both vertically and horizontally, between bacteria of the same and different species. Pathogenic Yersinia enterocolitica harbors a 70-kb virulence plasmid (pYV) that encodes genes for low calcium response, crystal violet (CV) binding, Congo red uptake, autoagglutination (AA), hydrophobicity (HP), type III secretion channels, host immune suppression factors, and biofilm formation. Ionizing radiation and modified atmosphere packaging (MAP) are used to control foodborne pathogens and meat spoilage. In this study, the effect of gamma radiation and modified atmosphere (air, 100% N2 , 75% N2 : 25% CO2 , 50% N2 : 50% CO2 , 25% N2 : 75% CO2 , 100% CO2 ) were examined by using the CV binding phenotype, for the presence or absence of pYV in Y. enterocolitica, suspended in raw ground pork. All Y. enterocolitica serovars used (O:3, O:8, and O5,27) were more sensitive to radiation as the CO2 concentration increased above 50%. Crystal violet binding following a radiation dose of 1.0 kGy, which reduced the Y. enterocolitica serovars >5 log, was greatest in the presence of air (ca. 8%), but was not affected by N2 or CO2 concentration (ca. 5%). Following release from modified atmosphere after irradiation, the loss of CV binding rose from 5% to 8% immediately following irradiation to >30% after outgrowth at 25 °C for 24 h. These results, using Y. enterocolitica as a model system, indicate that the risk of foodborne illness could be affected by the loss of virulence factors when postprocess intervention technologies are used. Provides gamma radiation D10 data for inactivation data for Y. enterocolitica irradiated under modified atmosphere and information to risk assessors regarding the difference between pathogen presence versus actual virulence. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Microbiological safety of retail vacuum-packed and modified-atmosphere-packed cooked meats at end of shelf life.

PubMed

Sagoo, S K; Little, C L; Allen, G; Williamson, K; Grant, K A

2007-04-01

A study of retail modified-atmosphere-packed and vacuum-packed cooked ready-to-eat meats was undertaken from September through mid-November 2003 to determine the microbiological quality at the end of shelf life and to establish any risk factors in the production, storage, and display of this product. Examination of 2,981 samples using Microbiological Guidelines criteria revealed that 66% were of satisfactory or acceptable microbiology quality, 33% were of unsatisfactory quality mainly due to high aerobic colony counts and Enterobacteriaceae concentrations, and 1% were of unacceptable quality due to the presence of Listeria monocytogenes at 100 CFU/g or higher (27 samples; range of 10(2) to 106 CFU/g) and Campylobacter jejuni (1 sample), indicating a risk to health. All samples at the end of the shelf life had satisfactory (<20 CFU/g) and/or acceptable (<102 CFU/g) levels of Staphylococcus aureus and Clostridium perfringens, four samples (<1%) had unsatisfactory levels of Escherichia coli (range of 102 to 106 CFU/g) and 5.5% of the samples contained L. monocytogenes at <20 CFU/g (4.8%) or between 20 and 100 CFU/g (0.7%). More samples of chicken (45%; 224 of 495 samples), beef (43%; 160 of 371 samples), and turkey (41%; 219 of 523 samples) were of unsatisfactory or unacceptable quality compared with ham (23%; 317 of 1,351 samples) or pork (32%; 67 of 206 samples). Twelve different L. monocytogenes typing characters (serotype-amplified fragment length polymorphism type-phage type) were evaluated for isolates recovered from samples of unacceptable quality, and the 1/2-IX-NT type was recovered from almost half (48%) of these samples. Salmonella was not detected in any samples examined. Risk factors identified for cooked meats that were microbiologically contaminated more frequently included vacuum packaging, packaging on retail premises, slicing, temperature not monitored in display units, and no hazard analysis system in place. Results from this study also suggest that the shelf life assigned to some modified-atmosphere-packed and vacuum-packed meats may not be appropriate.

Effect of modified atmosphere packaging for keeping gel-forming ability of lizardfish

NASA Astrophysics Data System (ADS)

Oka, Hiroyasu; Wang, Xi-Chang

In order to make clear the deterioration and its control for the gel-forming ability of lizardfish, formaldehyde (FA) and tyrosine (Tyr) accumulated in the fillets packaged with air, nitrogen (N2) and oxygen (O2) were determined during storage at 5°C. Amount of Tyr had no increase, however, th at of FA increased especially in the samples packed with N2 on the earlier periods of storage. It was presumed that an enzyme trimethylamine N-oxide demethylase (TMAOase) in the fillets acts sufficiently under oxygen-deficient storage, and the produced FA is rapidly combined with fish protein, causing the deterioration of the gel-forming ability, before protease of fillets act on the fish protein. These findings suggested that avoidance of oxygen deficiency during storage is eftective to keep gelforming ability of lizardfish.

Carbon monoxide concentration and exposure time effects on the depth of CO penetration and surface color of raw and cooked beef longissimus lumborum steaks.

PubMed

Sakowska, A; Guzek, D; Głąbska, D; Wierzbicka, A

2016-11-01

This study investigated the influence of carbon monoxide (CO) exposure time (0, 7, 14, and 21days) and concentration in gas mixture on depth of penetration and the surface color of raw and cooked striploin steaks. Seven packaging treatments were evaluated: vacuum, vacuum after 48h of exposure to 0.1%, 0.3% or 0.5% CO (mixed with 30% CO2 and 69.5-69.9% N2), and modified atmosphere packaging (MAP) containing the same gas mixtures. CO penetration depth increased as exposure times and CO concentration in gas mixtures increased (p<0.05). However, the carboxymyoglobin that formed did not always turn brown during thermal treatment. In cooked samples treated with 0.3% and 0.5% CO-MAP, a red carboxymyoglobin border was visible at the cross section, whereas other CO packaging treatments had its partial or total browning. To create a red color in raw and avoid a red boarder in cooked beef, up to 0.5% CO in vacuum packages and only 0.1% for MAP can be recommended. Copyright © 2016 Elsevier Ltd. All rights reserved.

Addressable microshutter array for a high-performance infrared miniature dispersive spectrometer

NASA Astrophysics Data System (ADS)

Ilias, S.; Picard, F.; Larouche, C.; Kruzelecky, R.; Jamroz, W.

2009-02-01

Programmable microshutter arrays were designed to improve the attainable signal to noise ratio (SNR) of a miniature dispersive spectrometer developed for space applications. Integration of a microshutter array to this instrument provides advantages such as the addition of a binary coded optical input operation mode for the miniature spectrometer which results in SNR benefits without spectral resolution loss. These arrays were successfully fabricated using surface micromachining technology. Each microshutter is basically an electrostatic zipping actuator having a curved shape. Applying critical voltage to one microshutter pulls the actuator down to the substrate and closes the associated slit. Opening of the microslits relies on the restoring force generated within the actuated zippers. High light transmission is obtained with the actuator in the open position and excellent light blocking is observed when the shutter is closed. The pull-in voltage to close the microslits was about 110 V and the response times to close and open the microslits were about 2 ms and 7 ms, respectively. Selected array dies were mounted in modified off-the-shelf ceramic packages and electrically connected to package pins. The packages were hermetically sealed with AR coated sapphire windows. This last packaging step was performed in a dry nitrogen controlled atmosphere.

Shelf-life of almond pastry cookies with different types of packaging and levels of temperature.

PubMed

Romeo, F V; De Luca, S; Piscopo, A; Santisi, V; Poiana, M

2010-06-01

Almond pastries are typical cookies of the south of Italy. Introduction of new packaging for this kind of cookies requires shelf-life assessments. This study, related to different types of packaging under various storage conditions of time and temperature, identifies critical parameters, as color and texture, to track during storage studies and to extend the shelf-life. The cookies were packed in three different ways and stored at two different temperatures. The pastries were separately stored: (1) in polyvinylchloride film; (2) in aluminum foil (ALL); (3) with modified atmosphere (MAP) in plastic vessels sealed into a polyamide/ polyethylene film; and (4) in vessels without any polymeric film. The storage temperatures were 20 and 30 °C. Evolution of texture, water activity, dry matter and color was assessed. Texture was evaluated by a texture analyzer with a puncturing test. Indices for hardening were the area under the curve (N × mm) up to 10 mm of distance, and the maximum force (N) corresponding to the crust fracture. The best results were obtained with ALL packaging and MAP condition, and above all, in all the trials a temperature of 30 °C reduced the crust hardness.

Regarding retrievals of methane in the atmosphere from IASI/Metop spectra and their comparison with ground-based FTIR measurements data

NASA Astrophysics Data System (ADS)

Khamatnurova, M. Yu.; Gribanov, K. G.; Zakharov, V. I.; Rokotyan, N. V.; Imasu, R.

2017-11-01

The algorithm for atmospheric methane distribution retrieval in atmosphere from IASI spectra has been developed. The feasibility of Levenberg-Marquardt method for atmospheric methane total column amount retrieval from the spectra measured by IASI/METOP modified for the case of lack of a priori covariance matrices for methane vertical profiles is studied in this paper. Method and algorithm were implemented into software package together with iterative estimation of a posteriori covariance matrices and averaging kernels for each individual retrieval. This allows retrieval quality selection using the properties of both types of matrices. Methane (XCH4) retrieval by Levenberg-Marquardt method from IASI/METOP spectra is presented in this work. NCEP/NCAR reanalysis data provided by ESRL (NOAA, Boulder, USA) were taken as initial guess. Surface temperature, air temperature and humidity vertical profiles are retrieved before methane vertical profile retrieval. The data retrieved from ground-based measurements at the Ural Atmospheric Station and data of L2/IASI standard product were used for the verification of the method and results of methane retrieval from IASI/METOP spectra.

Effects of Hydrated Potato Starch on the Quality of Low-fat Ttoekgalbi (Korean Traditional Patty) Packaged in Modified Atmosphere Conditions during Storage.

PubMed

Muhlisin, S M Kang; Choi, W H; Lee, K T; Cheong, S H; Lee, S K

2012-05-01

This study was carried out to investigate the effects of hydrated potato starch on the quality of low-fat ttoekgalbi (Korean traditional patty) packaged in modified atmosphere conditions during storage. The ttoekgalbi was prepared from 53.2% lean beef, 13.9% lean pork, 9.3% pork fat, and 23.6% other ingredients. Two low-fat ttoekgalbi treatments were prepared by substituting pork fat with hydrated potato starch; either by 50% fat replacement (50% FR) or 100% fat replacement (100% FR). Both 50% and 100% FR increased the moisture, crude protein, and decreased fat content, cooking loss, and hardness. For MAP studies, 200 g of ttoekgalbi were placed on the tray and filled with gas composed of 70% O2: 30% CO2 (70% O2-MAP) and 30% CO2: 70% N2 (70% N2-MAP), and were stored at 5°C for 12 d. During the storage time, both 50% and 100% FR showed higher protein deterioration, while no differences were found in CIE a*, CIE L*, lipid oxidation, and bacterial counts in comparison to control. The ttoekgalbi with 70% O2-MAP was more red, lighter in color, and showed higher TBARS values compared with 70% N2-MAP. The meat with 70% N2-MAP showed lower aerobic bacterial counts in control than those with 70% O2-MAP. The lower anaerobic bacterial counts were observed only in 50% FR and 100% FR packed with 70% N2-MAP in comparison with 70% O2-MAP. In conclusion, the fat replacement with hydrated potato starch showed no negative effects on the quality of low fat ttoekgalbi during storage and 70% N2-MAP was better than 70% O2-MAP for low-fat ttoekgalbi packaging.

Combined modified atmosphere packaging and low temperature storage delay lignification and improve the defense response of minimally processed water bamboo shoot.

PubMed

Song, Lili; Chen, Hangjun; Gao, Haiyan; Fang, Xiangjun; Mu, Honglei; Yuan, Ya; Yang, Qian; Jiang, Yueming

2013-09-04

Minimally processed water bamboo shoot (WBS) lignifies and deteriorates rapidly at room temperature, which limits greatly its marketability. This study was to investigate the effect of modified atmosphere packaging (MAP) on the sensory quality index, lignin formation, production of radical oxygen species (ROS) and activities of scavenging enzymes, membrane integrity and energy status of minimally processed WBS when packaged with or without the sealed low-density polyethylene (LDPE) bags, and then stored at 20°C for 9 days or 2°C for 60 days. The sensory quality of minimally processed WBS decreased quickly after 6 days of storage at 20°C. Low temperature storage maintained a higher sensory quality index within the first 30 days, but exhibited higher contents of lignin and hydrogen peroxide (H2O2) as compared with non-MAP shoots at 20°C. Combined MAP and low temperature storage not only maintained good sensory quality after 30 days, but also reduced significantly the increases in lignin content, superoxide anion (O2.-) production rate, H2O2 content and membrane permeability, maintained high activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), and reduced the increase in activities of lipase, phospholipase D (PLD) and lipoxygenase (LOX). Furthermore, the minimally processed WBS under MAP condition exhibited higher energy charge (EC) and lower adenosine monophosphate (AMP) content by the end of storage (60 days) at 2°C than those without MAP or stored for 9 days at 20°C. These results indicated that MAP in combination with low temperature storage reduced lignification of minimally processed WBS, which was closely associated with maintenance of energy status and enhanced activities of antioxidant enzymes, as well as reduced alleviation of membrane damage caused by ROS.

Combined modified atmosphere packaging and low temperature storage delay lignification and improve the defense response of minimally processed water bamboo shoot

PubMed Central

2013-01-01

Background Minimally processed water bamboo shoot (WBS) lignifies and deteriorates rapidly at room temperature, which limits greatly its marketability. This study was to investigate the effect of modified atmosphere packaging (MAP) on the sensory quality index, lignin formation, production of radical oxygen species (ROS) and activities of scavenging enzymes, membrane integrity and energy status of minimally processed WBS when packaged with or without the sealed low-density polyethylene (LDPE) bags, and then stored at 20°C for 9 days or 2°C for 60 days. Results The sensory quality of minimally processed WBS decreased quickly after 6 days of storage at 20°C. Low temperature storage maintained a higher sensory quality index within the first 30 days, but exhibited higher contents of lignin and hydrogen peroxide (H2O2) as compared with non-MAP shoots at 20°C. Combined MAP and low temperature storage not only maintained good sensory quality after 30 days, but also reduced significantly the increases in lignin content, superoxide anion (O2.-) production rate, H2O2 content and membrane permeability, maintained high activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), and reduced the increase in activities of lipase, phospholipase D (PLD) and lipoxygenase (LOX). Furthermore, the minimally processed WBS under MAP condition exhibited higher energy charge (EC) and lower adenosine monophosphate (AMP) content by the end of storage (60 days) at 2°C than those without MAP or stored for 9 days at 20°C. Conclusion These results indicated that MAP in combination with low temperature storage reduced lignification of minimally processed WBS, which was closely associated with maintenance of energy status and enhanced activities of antioxidant enzymes, as well as reduced alleviation of membrane damage caused by ROS. PMID:24006941

Color stability of ground beef packaged in a low carbon monoxide atmosphere or vacuum.

PubMed

Jeong, Jong Youn; Claus, James R

2011-01-01

Ground beef was either packaged in an atmosphere of 0.4% CO, 30% CO₂, and 69.6% N₂ (CO-MAP) or vacuum. After storage (48 h, 2-3°C), packages of CO-MAP and vacuum were opened and overwrapped with polyvinyl chloride. Other CO-MAP and vacuum packages were left intact. Packages were initially displayed for 7 days (2-3°C). Intact packages were further displayed up to 35 days before being opened and displayed (1 or 3 days). Intact CO-MAP packaged ground beef was always more red than intact vacuum-packaged ground beef. Color was relatively stable for both types of intact packages over 35 days of display. Upon opening CO-MAP packaged ground beef, the red color decreased slower than in ground beef from vacuum packages. Published by Elsevier Ltd.

Interactions between sanitizers and packaging gas compositions and their effects on the safety and quality of fresh-cut onions (Allium cepa L.).

PubMed

Page, Natalie; González-Buesa, Jaime; Ryser, Elliot T; Harte, Janice; Almenar, Eva

2016-02-02

Onions are one of the most widely utilized vegetables worldwide, with demand for fresh-cut onions steadily increasing. Due to heightened safety concerns and consumer demand, the implications of sanitizing and packaging on fresh-cut onion safety and quality need to be better understood. The objective of this study was to investigate the effect of produce sanitizers, in-package atmospheres, and their interactions on the growth of Salmonella Typhimurium, mesophilic aerobic bacteria, yeast and mold, and the physico-chemical quality of diced onions to determine the best sanitizer and in-package atmosphere combination for both safety and quality. Diced onions were inoculated or not with S. Typhimurium, sanitized in sodium hypochlorite, peroxyacetic acid, or liquid chlorine dioxide, and then packaged in either polylactic acid bags containing superatmospheric O2, elevated CO2/reduced O2, or air, or in polyethylene terephthalate snap-fit containers. Throughout 14 days of storage at 7 °C, packaged diced onions were assessed for their safety (S. Typhimurium), and quality (mesophilic aerobic bacteria, yeasts and molds, physico-chemical analyses, and descriptive and consumer acceptance sensory panels). While sanitizer affected (P<0.05) fewer parameters (S. Typhimurium, mesophiles, yeasts and molds, headspace CO2, weight loss, and pH), in-package atmosphere had a significant (P<0.05) effect on all parameters evaluated. Two-way interactions between sanitizer and atmosphere that affected S. Typhimurium and pH were identified whereas 3-way interactions (sanitizer, atmosphere and time) were only observed for headspace CO2. Sodium hypochlorite and elevated CO2/reduced O2 was the best sanitizer and in-package atmosphere combination for enhancing the safety and quality of packaged diced onions. In addition, this combination led to diced onions acceptable for purchase after 2 weeks of storage by trained and consumer panels. Copyright © 2015 Elsevier B.V. All rights reserved.

Open-source Software for Exoplanet Atmospheric Modeling

NASA Astrophysics Data System (ADS)

Cubillos, Patricio; Blecic, Jasmina; Harrington, Joseph

2018-01-01

I will present a suite of self-standing open-source tools to model and retrieve exoplanet spectra implemented for Python. These include: (1) a Bayesian-statistical package to run Levenberg-Marquardt optimization and Markov-chain Monte Carlo posterior sampling, (2) a package to compress line-transition data from HITRAN or Exomol without loss of information, (3) a package to compute partition functions for HITRAN molecules, (4) a package to compute collision-induced absorption, and (5) a package to produce radiative-transfer spectra of transit and eclipse exoplanet observations and atmospheric retrievals.

An apple a day does not always keep the doctor away....

PubMed

Dedouit, Fabrice; Tournel, Gilles; Robert, Anne Bécart; Dutrieux, Pierre; Hédouin, Valéry; Gosset, Didier

2008-11-01

The authors describe a case of suicide in the workplace. A 45-year-old man employed by a fruit and vegetable packing company was found dead in a room containing a modified atmosphere for the packaging of fruits and vegetables. The rescue team measured the carbon monoxide (CO) concentration of the ambient air with a digital CO tester and found a level higher than 600 particles per million. Analysis of an arterial blood sample taken with an airtight syringe revealed the absence of CO but high levels of carbon dioxide (CO(2)). Autopsy revealed no significant injury and police investigators found a handwritten note of intent, describing a recent personal crisis. The authors concluded that the cause of death was suicide by asphyxiation secondary to CO(2) intoxication and notably oxygen (O(2)) depletion. This manner of suicide is rare and most cases previously described in the literature were accidental intoxications. To the best of our knowledge, this is the first case of suicide by CO(2) intoxication and O(2) depletion in a room with a modified atmosphere.

Effect of superatmospheric oxygen packaging on sensorial quality, spoilage, and Listeria monocytogenes and Aeromonas caviae growth in fresh processed mixed salads.

PubMed

Allende, Ana; Jacxsens, Liesbeth; Devlieghere, Frank; Debevere, Johan; Artés, Francisco

2002-10-01

Atmospheres with O2 levels higher than 70 kPa have recently been suggested as an innovation to modified atmosphere packaging (MAP) for fresh processed vegetables to maintain sensory quality and safety. In the present work, mixed vegetable salad collected from a commercial processing plant and stored with the MAP technique was studied. Two gas mixtures were actively generated by using an initial O2 concentration of 95 kPa and combined with two plastic films. The low-barrier film permeability for O2 was 1,629 mlO2/m2 x 24 h x atm with 30 microm of thickness (Hyplast, Hoogstraten, Belgium) and the O2 permeability of the high-barrier film was 2 mlO2/m2 x 24h x atm with 150 microm of thickness (Euralpack, Wommelgen, Belgium) at 23 degrees C. As control, active conventional MAP with application of 3 to 5 kPa of O2 and 6 to 8 kPa of CO2 was used. Packaged salads were stored up to 8 days at 4 degrees C and at temperatures simulating chilled distribution chain conditions. Microbial safety and sensory quality, as well as the survival of inoculated Listeria monocytogenes and Aeromonas caviae, were monitored. The effect of superatmospheric O2 on the growth of aerobic microflora was variable. Under superatmospheric conditions, lactic acid bacteria and members of Enterobacteriaceae were inhibited. Nevertheless, growth of yeast and A. caviae seem to be stimulated by superatmospheric O2, whereas growth of psychrotrophic bacteria and L monocytogenes was not affected. The overall visual appearance (mainly color) of the mixed vegetable salads was better maintained and the shelf life prolonged when packaged under O2 concentrations greater than 50 kPa.

Quality assessment of ice-stored tropical yellowfin tuna (Thunnus albacares) and influence of vacuum and modified atmosphere packaging.

PubMed

Silbande, Adèle; Adenet, Sandra; Smith-Ravin, Juliette; Joffraud, Jean-Jacques; Rochefort, Katia; Leroi, Françoise

2016-12-01

Metagenomic, microbial, chemical and sensory analyses of Thunnus albacares from Martinique stored in ice (AIR - 0 °C), vacuum (VP - 4/8 °C) and modified atmosphere packaging (MAP - 4/8 °C) (70% CO2 - 30% O2) were carried out. The organoleptic rejection of AIR tuna was observed at day 13 when total bacterial counts equaled 10(6)-10(7) CFU g(-1). No extension of shelf-life was provided by VP and MAP. According to 16S rRNA gene sequence analyzed by Illumina MiSeq and PCR-TTGE, Rhodanobacter terrae was the main species of the freshly caught tuna. At the sensory rejection time, Brochothrix thermosphacta and Pseudomonas dominated the AIR products while B. thermosphacta alone or a mix of B. thermosphacta, Enterobacteriaceae and lactic acid bacteria (LAB) dominated the microbiota of MAP and VP products, respectively. The pH value remained stable in all trials, ranging from 5.77 to 5.97. Total volatile basic nitrogen (TVBN) and trimethylamine (TMA-N) concentrations were weak and not significantly different between batches. Lipid oxidation increased in the samples containing O2 (MAP > AIR). The initial concentration of histamine was high (75-78 mg kg(-1)) and stable up to 8 days but then significantly decreased in all trials to reach 25-30 mg kg(-1), probably due to the presence of histamine-decomposing bacteria. Copyright © 2016 Elsevier Ltd. All rights reserved.

Combined effect of oregano essential oil and modified atmosphere packaging on shelf-life extension of fresh chicken breast meat, stored at 4 degrees C.

PubMed

Chouliara, E; Karatapanis, A; Savvaidis, I N; Kontominas, M G

2007-09-01

The combined effect of oregano essential oil (0.1% and 1% w/w) and modified atmosphere packaging (MAP) (30% CO2/70% N2 and 70% CO2/30% N2) on shelf-life extension of fresh chicken meat stored at 4 degrees C was investigated. The parameters that were monitored were: microbiological (TVC, Pseudomonas spp., lactic acid bacteria (LAB), yeasts, Brochothrix thermosphacta and Enterobacteriaceae), physico-chemical (pH, TBA, color) and sensory (odor and taste) attributes. Microbial populations were reduced by 1-5 log cfu/g for a given sampling day, with the more pronounced effect being achieved by the combination of MAP and oregano essential oil. TBA values for all treatments remained lower than 1 mg malondialdehyde (MDA) kg(-1) throughout the 25-day storage period. pH values varied between 6.4 (day 0) and 5.9 (day 25). The values of the color parameters L*, a* and b* were not considerably affected by oregano oil or by MAP. Finally, sensory analysis showed that oregano oil at a concentration of 1% imparted a very strong taste to the product for which reason these lots of samples were not scored. On the basis of sensory evaluation a shelf-life extension of breast chicken meat by ca. 3-4 days for samples containing 0.1% oregano oil, 2-3 days for samples under MAP and 5-6 days for samples under MAP containing 0.1% of oregano oil was attained. Thus oregano oil and MAP exhibited an additive preservation effect.

Modelling growth of Escherichia coli O157:H7 in fresh-cut lettuce submitted to commercial process conditions: chlorine washing and modified atmosphere packaging.

PubMed

Posada-Izquierdo, Guiomar D; Pérez-Rodríguez, Fernando; López-Gálvez, Francisco; Allende, Ana; Selma, María V; Gil, María I; Zurera, Gonzalo

2013-04-01

Fresh-cut iceberg lettuce inoculated with Escherichia coli O157:H7 was submitted to chlorine washing (150 mg/mL) and modified atmosphere packaging on laboratory scale. Populations of E. coli O157:H7 were assessed in fresh-cut lettuce stored at 4, 8, 13 and 16 °C using 6-8 replicates in each analysis point in order to capture experimental variability. The pathogen was able to grow at temperatures ≥8 °C, although at low temperatures, growth data presented a high variability between replicates. Indeed, at 8 °C after 15 days, some replicates did not show growth while other replicates did present an increase. A growth primary model was fitted to the raw growth data to estimate lag time and maximum growth rate. The prediction and confidence bands for the fitted growth models were estimated based on Monte-Carlo method. The estimated maximum growth rates (log cfu/day) corresponded to 0.14 (95% CI: 0.06-0.31), 0.55 (95% CI: 0.17-1.20) and 1.43 (95% CI: 0.82-2.15) for 8, 13 and 16 °C, respectively. A square-root secondary model was satisfactorily derived from the estimated growth rates (R(2) > 0.80; Bf = 0.97; Af = 1.46). Predictive models and data obtained in this study are intended to improve quantitative risk assessment studies for E. coli O157:H7 in leafy green products. Copyright © 2012. Published by Elsevier Ltd.

Role of Broiler Carcasses and Processing Plant Air in Contamination of Modified-Atmosphere-Packaged Broiler Products with Psychrotrophic Lactic Acid Bacteria▿

PubMed Central

Vihavainen, Elina; Lundström, Hanna-Saara; Susiluoto, Tuija; Koort, Joanna; Paulin, Lars; Auvinen, Petri; Björkroth, K. Johanna

2007-01-01

Some psychrotrophic lactic acid bacteria (LAB) are specific meat spoilage organisms in modified-atmosphere-packaged (MAP), cold-stored meat products. To determine if incoming broilers or the production plant environment is a source of spoilage LAB, a total of 86, 122, and 447 LAB isolates from broiler carcasses, production plant air, and MAP broiler products, respectively, were characterized using a library of HindIII restriction fragment length polymorphism (RFLP) patterns of the 16 and 23S rRNA genes as operational taxonomic units in numerical analyses. Six hundred thirteen LAB isolates from the total of 655 clustered in 29 groups considered to be species specific. Sixty-four percent of product isolates clustered either with Carnobacterium divergens or with Carnobacterium maltaromaticum type strains. The third major product-associated cluster (17% of isolates) was formed by unknown LAB. Representative strains from these three clusters were analyzed for the phylogeny of their 16S rRNA genes. This analysis verified that the two largest RFLP clusters consisted of carnobacteria and showed that the unknown LAB group consisted of Lactococcus spp. No product-associated LAB were detected in broiler carcasses sampled at the beginning of slaughter, whereas carnobacteria and lactococci, along with some other specific meat spoilage LAB, were recovered from processing plant air at many sites. This study reveals that incoming broiler chickens are not major sources of psychrotrophic spoilage LAB, whereas the detection of these organisms from the air of the processing environment highlights the role of processing facilities as sources of LAB contamination. PMID:17142357

The growth of Listeria monocytogenes in cheese packed under a modified atmosphere.

PubMed

Whitley, E; Muir, D; Waites, W M

2000-01-01

The effect of modified atmosphere Packaging (MAP) on the growth of Listeria monocytogenes in mould ripened cheeses was studied at refrigeration temperatures (2-8.3 degrees C) over a storage period of 6 weeks. Control experiments in cling film with no atmospheric modification produced a lag time before growth of up to 1 week and rapid subsequent growth. MAP with a CO2 concentration of less than 20% allowed growth to occur but when O2 was incorporated; the lag time was reduced from 3 to 2 weeks and subsequent growth was also faster, producing an increase in cell numbers of 1.4 log cycles over the incubation period. N2-MAP in the absence of O2 increased the lag time to 3 weeks and slowed growth, while the inclusion of CO2 extended the lag to 3 weeks and slowed subsequent growth even more. In MAP with 80:10:10 (v/v/v) N2:CO2:O2, there was a lag period of 2-3 weeks before growth of L. monocytogenes occurred, while the total viable aerobic count (TVAC) decreased by 2-3 log cycles and the total Lactobacillus count showed little change. It was concluded that MAP was not suitable for preventing the growth of L. monocytogenes in such cheeses.

Quality changes of fresh-cut kohlrabi sticks under modified atmosphere packaging.

PubMed

Escalona, V H; Aguayo, E; Artés, F

2007-06-01

The aim of this study was to determine the effect of different gas compositions on quality attributes and shelf life of kohlrabi sticks stored in modified atmosphere up to 14 d at 0 degrees C. Two commercial films were tested: oriented polypropylene (OPP) and amide-polyethylene (amide-PE). As a control, a microperforated OPP film was used. In order to study the changes in metabolic activity by minimal processing, the respiration rate and ethylene production at 0 degrees C were monitored for both intact stems and sticks. Changes in color, chemical parameters, sugars and organic acid contents, and sensorial quality of kohlrabi sticks were evaluated. An initial ethylene production of sticks was 13-fold higher than that of intact stems; meanwhile CO(2) production was 2-fold higher. However after 4 d of storage, a similar respiration rate for stems and sticks was found. Also the ethylene production of sticks and stems was steady around 15 to 20 nL/kg(/)h after 10 d. Kohlrabi sticks showed a little change in chemical parameters and very low weight losses during cold storage. Sticks under an equilibrium atmosphere of 7 kPa O(2) and 9 kPa CO(2) at 0 degrees C reached by amide-PE kept an acceptable sensorial quality for 14 d.

Recent innovations in edible and/or biodegradable packaging materials.

PubMed

Guilbert, S; Cuq, B; Gontard, N

1997-01-01

Certain newly discovered characteristics of natural biopolymers should make them a choice material to be used for different types of wrappings and films. Edible and/or biodegradable packagings produced from agricultural origin macromolecules provide a supplementary and sometimes essential means to control physiological, microbiological, and physicochemical changes in food products. This is accomplished (i) by controlling mass transfers between food product and ambient atmosphere or between components in heterogeneous food product, and (iii) by modifying and controlling food surface conditions (pH, level of specific functional agents, slow release of flavour compounds), it should be stressed that the material characteristics (polysaccharide, protein, or lipid, plasticized or not, chemically modified or not, used alone or in combination) and the fabrication procedures (casting of a film-forming solution, thermoforming) must be adapted to each specific food product and usage condition (relative humidity, temperature). Some potential uses of these materials (e.g. wrapping of various fabricated foods; protection of fruits and vegetables by control of maturation; protection of meat and fish; control of internal moisture transfer in pizzas), which are hinged on film properties (e.g. organoleptic, mechanical, gas and solute barrier) are described with examples.

Effect of vacuum and modified atmosphere packaging on the microbiological, chemical and sensory properties of tropical red drum (Sciaenops ocellatus) fillets stored at 4°C.

PubMed

Silbande, Adèle; Adenet, Sandra; Chopin, Christine; Cornet, Josiane; Smith-Ravin, Juliette; Rochefort, Katia; Leroi, Françoise

2018-02-02

The effect of vacuum (VP - 4°C) and CO 2 /N 2 -atmosphere (MAP - 4°C) packaging on the quality of red drum fillets compared with whole gutted iced fish was investigated. A metagenomic approach, bacterial enumeration and isolation, biochemical and sensory analyses were carried out. The organoleptic rejection of whole fish was observed at day 15 whereas VP and MAP fillets appeared unacceptable only after 29days. At these dates, total mesophilic counts reached 10 7 -10 8 CFU g -1 . According to Illumina MiSeq sequencing, Arthrobacter, Chryseobacterium, Brevibacterium, Staphylococcus and Kocuria were the main genera of the fresh red drum fillets. At the sensory rejection time, lactic acid bacteria (LAB), particularly Carnobacterium sp., dominated the microbiota of both types of packaging. The pH value of fresh samples was between 5.96 and 6.37 and did not vary greatly in all trials. Total volatile basic nitrogen (TVBN) and trimethylamine (TMA) concentrations were low and not represent reliable indicators of the spoilage, contrary to some biogenic amines (cadaverine, putrescine and tyramine). Chilled packed fillets of red drum have an extended shelf-life compared to whole gutted iced fish. Overall, few differences in sensory and microbial quality were observed between the VP and MAP samples. Next-Generation Sequencing (NGS) provided data on the microbiota of a tropical fish. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of antimicrobial films for microbiological control of packaged salad.

PubMed

Muriel-Galet, Virginia; Cerisuelo, Josep P; López-Carballo, Gracia; Lara, Marta; Gavara, Rafael; Hernández-Muñoz, Pilar

2012-07-02

The aim of the present work was to characterize the antimicrobial efficiency of films consisting of PP/EVOH structures with oregano essential oil and citral. Both substances are known for their antimicrobial activity based on their interaction with the cell membrane. The films developed were used to pack minimally processed salads, combining modified atmosphere technology to extend shelf-life and active packaging technology to reduce possible microbiological risks. The antimicrobial activity of the films against the pathogenic microorganisms Escherichia coli, Salmonella enterica and Listeria monocytogenes and natural microflora was investigated "in vitro" and also on the food itself. The effect of release of the antimicrobial agent on the sensory characteristics of the salad was also studied. The results showed that antimicrobial activity reduced spoilage flora on the salad as well as inhibited the growth of pathogens in contaminated salads. This effect was greater against Gram-negative bacteria. Sensory studies showed that the package that was most effective and most accepted by customers was the one containing 5% oregano essential oil. Copyright © 2012 Elsevier B.V. All rights reserved.

Space shuttle food system study: Food and beverage package development, modification 8S

NASA Technical Reports Server (NTRS)

1976-01-01

A new, highly utile rehydration package was developed for foods in zero gravity. Rehydratable foods will become more acceptable as a result of their overall rehydration capability and improved palatability. This new package design is greatly enhanced by the specified spacecraft condition of atmospheric pressure; the pressure differential between the atmosphere and the package carries the functional responsibility for rapid food rehydration without excess package manipulation by the consumer. Crew acceptance will further be enhanced by less manipulation, hotter rehydration water temperatures and the ability to hold the foods at preparation temperatures until they are consumed.

Effect of including whole linseed and vitamin E in the diet of young bulls slaughtered at two fat covers on the sensory quality of beef packaged in two different packaging systems.

PubMed

Albertí, Pere; Campo, María M; Beriain, María J; Ripoll, Guillermo; Sañudo, Carlos

2017-02-01

Forty-six Pirenaica young bulls, slaughtered at two levels of fatness (3 and 4 mm), were used to evaluate the effect of the inclusion of 50 g kg -1 linseed alone or with 200 IU vitamin E kg -1 in the concentrate and of the meat packaging system (vacuum or modified atmosphere packaging (MAP)) on the beef sensory quality. The inclusion of linseed or supplementation with vitamin E in the concentrate induced no significant differences in the main meat sensory scores and overall appraisal except under MAP, where small differences due to concentrate ingredients were found in juiciness and metallic flavor intensity. Extending the display time up to 4 or 8 days in high-oxygen MAP had detrimental effects on sensory attributes. Meat from animals with 4 mm fat cover depth were rated more tender and juicy, less fibrous and with a higher intensity of beef flavor and rancid odor than meat from 3 mm fat cover bulls when both samples were vacuum packaged. The inclusion of 50 g kg -1 linseed in the concentrate fed to bulls had no detrimental effect on the beef sensory quality. The vacuum-packaged meat of bulls slaughtered at 4 mm fat cover was rated higher on sensory analysis than that at 3 mm fat cover. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Shelf-Life of Boiled Salted Duck Meat Stored Under Normal and Modified Atmosphere.

PubMed

Zhai, Yang; Huang, Jichao; Khan, Iftikhar Ali; Guo, Yuchen; Huang, Ming; Zhou, Guanghong

2018-01-01

The objective of this study was to investigate the physicochemical properties and changes in the microbial counts of boiled salted duck (BSD) meat packed under various conditions. BSD meat was stored under normal atmosphere (C) and two modified atmosphere packaging (MAP) conditions: M1 (N 2 , 100%) and M2 (CO 2 /N 2 , 30%/70%) at 4 °C. Microbiological quality, pH, redness, lipid oxidation, headspace gas composition, and water activity of BSD meat were measured. The results showed that the time to reach the maximum acceptable total viable counts (TVC, 4.9 log CFU/g) was 12, 18, and 21 d in C, M1, and M2 samples, respectively. Significant difference in the redness values was observed in all treatments during storage. The redness value of C group was significantly lower than that in M1 and M2 groups at the end of storage. The thiobarbituric acid-reactive substances (TBARS) values under MAP were 0.24 to 0.26 mg MDA/kg meat at the end of storage, lower (P < 0.05) than that in C group (0.78 mg MDA/kg meat). The water activity in M2 group was the lowest among all 3 groups. The CO 2 concentration in M2 decreased significantly during storage. Our study demonstrates that packaging with 30% CO 2 and 70% N 2 (M2) could extend the shelf-life of BSD meat to 21 d during storage at 4 °C, suggesting that MAP can be a practical approach to extend the shelf-life and maintain the quality of BSD products. This study evaluated the application of MAP for a cooked duck product. Our results showed that MAP can be utilized to extend the shelf-life. This technology may be used for preservation of other cooked meat products. © 2017 Institute of Food Technologists®.

An Open-source Meteorological Operational System and its Installation in Portuguese- speaking Countries

NASA Astrophysics Data System (ADS)

Almeida, W. G.; Ferreira, A. L.; Mendes, M. V.; Ribeiro, A.; Yoksas, T.

2007-05-01

CPTEC, a division of Brazil’s INPE, has been using several open-source software packages for a variety of tasks in its Data Division. Among these tools are ones traditionally used in research and educational communities such as GrADs (Grid Analysis and Display System from the Center for Ocean-Land-Atmosphere Studies (COLA)), the Local Data Manager (LDM) and GEMPAK (from Unidata), andl operational tools such the Automatic File Distributor (AFD) that are popular among National Meteorological Services. In addition, some tools developed locally at CPTEC are also being made available as open-source packages. One package is being used to manage the data from Automatic Weather Stations that INPE operates. This system uses only open- source tools such as MySQL database, PERL scripts and Java programs for web access, and Unidata’s Internet Data Distribution (IDD) system and AFD for data delivery. All of these packages are get bundled into a low-cost and easy to install and package called the Meteorological Data Operational System. Recently, in a cooperation with the SICLIMAD project, this system has been modified for use by Portuguese- speaking countries in Africa to manage data from many Automatic Weather Stations that are being installed in these countries under SICLIMAD sponsorship. In this presentation we describe the tools included-in and and architecture-of the Meteorological Data Operational System.

Comparison of multiple atmospheric chemistry schemes in C-IFS

NASA Astrophysics Data System (ADS)

Flemming, Johannes; Huijnen, Vincent; Arteta, Joaquim; Stein, Olaf; Inness, Antje; Josse, Beatrice; Schultz, Martin; Peuch, Vincent-Henri

2013-04-01

As part of the MACCII -project (EU-FP7) ECMWF's integrated forecast system (IFS) is being extended by modules for chemistry, deposition and emission of reactive gases. This integration of the chemistry complements the integration of aerosol processes in IFS (Composition-IFS). C-IFS provides global forecasts and analysis of atmospheric composition. Its main motivation is to utilize the IFS for the assimilation of satellite observation of atmospheric composition. Furthermore, the integration of chemistry packages directly into IFS will achieve better consistency in terms of the treatment of physical processes and has the potential for simulating interactions between atmospheric composition and meteorology. Atmospheric chemistry in C-IFS can be represented by the modified CB05 scheme as implemented in the TM5 model and the RACMOBUS scheme as implemented in the MOCAGE model. An implementation of the scheme of the MOZART 3.5 model is ongoing. We will present the latest progress in the development and application of C-IFS. We will focus on the comparison of the different chemistry schemes in an otherwise identical C-IFS model setup (emissions, meteorology) as well as in their original Chemistry and Transport Model setup.

Oxidative stability of n-3-enriched chicken patties under different package-atmosphere conditions.

PubMed

Penko, Ana; Polak, Tomaž; Lušnic Polak, Mateja; Požrl, Tomaž; Kakovič, Damir; Žlender, Božidar; Demšar, Lea

2015-02-01

The oxidation processes were studied in chicken patties, enriched with n-3 fatty acids, after 8days of storage at 4°C, under different aerobic conditions, and following heat treatment. Significant effects were seen on lipid and cholesterol oxidation and the sensory qualities for whole flaxseed addition in the chicken feed (i.e., n-3 fatty acid enrichment), and for the different package-atmosphere conditions. For the raw chicken patties, n-3 enrichment increased the colour L(∗) values while, after the heat treatment, there were higher thiobarbituric acid-reactive substances (TBARs) and cholesterol oxidation products (COPs), and the rancidity was more pronounced. In comparison with the low O2 (<0.5%) package-atmosphere condition, O2 enrichment (80%) increased the instrumentally measured colour values, TBARs, total and individual COPs, and the rancidity became pronounced. The most suitable package-atmosphere condition of these raw n-3-enriched chicken patties is a very low O2 atmosphere, with or without an O2 scavenger. Copyright © 2014 Elsevier Ltd. All rights reserved.

National Meat Case Study 2004: Product labeling information, branding, and packaging trends.

PubMed

Reicks, A L; Brooks, J C; Kelly, J M; Kuecker, W G; Boillot, K; Irion, R; Miller, M F

2008-12-01

Fresh meat retail cases in 104 supermarkets across 5 regions of the United States were audited for the use of packaging types and materials, branding, and cooking/nutritional information. Frequency means were separated for species of beef, ground beef, pork, chicken, turkey, lamb, and veal. Traditional polyvinyl chloride overwrap was used on 47.0% of packages in the fresh meat case nationwide and was the most frequent packaging type for beef, ground beef, pork, lamb, and veal. The use of modified atmosphere packaging was greatest (P < 0.001) in ground beef (33.2%) and turkey (45.1%) products. The 3 most common tray colors in the fresh meat retail case on a national level were white (39.6%), yellow (22.4%), and black (11.5%). Foam trays were used in 72.6% of all packages in the retail meat case. In 2004, 60.2% of all packages were case-ready. Chicken (94.8%) and turkey (95.6%) products utilized case-ready packaging systems more (P < 0.001) than any other species. On a national level, 50.1% of all products carried a national brand, 12.2% carried a store brand, and the remaining 37.7% of products in the fresh meat case in 2004 were not branded. Chicken was most (P < 0.001) likely to carry a natural brand label. Labels with cooking instructions were found most (P < 0.001) on pork (37.3%) and turkey products (48.1%). Chicken (20.4%) and turkey products (20.7%) were most (P < 0.001) likely to have the cooking instructions printed on the packaging material compared with all other species. Labels with nutritional information were most (P < 0.001) likely to be found on turkey products (55.7%) in the fresh meat case compared with any other species. On the national level, 6.1% of all packages reported in the fresh meat case in 2004 were value-added.

Effects of electron-beam and gamma irradiation treatments on the microbial populations, respiratory activity and sensory characteristics of Tuber melanosporum truffles packaged under modified atmospheres.

PubMed

Rivera, Carmen Susana; Venturini, María Eugenia; Marco, Pedro; Oria, Rosa; Blanco, Domingo

2011-10-01

The effects of electron-beam or gamma irradiation (doses of 1.5 kGy and 2.5 kGy of either one) on the microbial populations, respiratory activity and sensory characteristics of Tuber melanosporum packaged under modified atmospheres were monitored immediately after treatment, and subsequently every seven days during 35 days of storage at 4 °C. Treatments with 1.5 and 2.5 kGy reduced the total mesophilic aerobes counts respectively by 4.3 and 5.6 log cfu/g for electron-beam treatment, and by 6.4 and 6.6 log cfu/g for gamma irradiation. Other microbial groups studied (Pseudomonas genus, Enterobacteriaceae family, lactic acid bacteria, mesophilic aerobic spores, molds and yeasts) were not detected after the treatments. A decrease in the respiratory activity was detected in all the irradiated batches, indicating that the carbon dioxide levels were lower and the oxygen levels higher than those of the non-irradiated ones. Two species of yeasts, Candida sake and Candida membranifaciens var. santamariae, survived the irradiation treatments and became the dominant microbial populations with counts of up to 7.0 log cfu/g. The growth of these microorganisms was visible on the surface of irradiated truffles from day 21 onwards, affecting the flavor and the general acceptability of the ascocarps. Moreover, a watery exudate was detected in the treated truffles from the third week onwards, so the application of irradiation treatments in doses equal to or above 1.5 kGy did not preserve the quality characteristics of T. melanosporum truffles beyond 28 days. Copyright © 2011 Elsevier Ltd. All rights reserved.

The effect of addition of olive oil and "Aceto balsamico di Modena" wine vinegar in conjunction with active atmosphere packaging on the microbial and sensory quality of "Lollo Verde" lettuce and rocket salad.

PubMed

Arvanitoyannis, Ioannis S; Bouletis, Achilleas D; Papa, Eirini A; Gkagtzis, Dimitrios C; Hadjichristodoulou, Christos; Papaloucas, C

2011-12-01

Fresh rocket "Eruca Sativa" and lettuce "Lollo Verde" leaves were stored with the addition of olive oil and wine vinegar "Aceto balsamico di Modena" under modified atmosphere packaging (MAP) (5% O(2)/10% CO(2)/85% N(2) for MAP A and 2% O(2)/5% CO(2)/93% N(2) for MAP B). The microbial (mesophilic, psychrotrophic bacteria and Enterobacteriacae), physical (color and firmness) and sensory parameters of samples were studied in relation to storage time (up to 10 days at 5 ± 1 °C). The effect of wine vinegar and the application of both MAP treatments reduced the growth of all bacteria populations (p < 0.05). Samples with olive oil stored under MAP A gave the best score for overall impression (3 and 2.1 for MAP A and B respectively at the 9th day of storage) while the addition of vinegar limited sensory shelf-life to 3 days (p < 0.05). Firmness was negatively affected by wine vinegar while samples with olive oil stored under MAP A maintained firmness close to normal. Color attributes were maintained better under both MAP treatments (p < 0.05). Copyright © 2011 Elsevier Ltd. All rights reserved.

A revised radiation package of G-packed McICA and two-stream approximation: Performance evaluation in a global weather forecasting model

NASA Astrophysics Data System (ADS)

Baek, Sunghye

2017-07-01

For more efficient and accurate computation of radiative flux, improvements have been achieved in two aspects, integration of the radiative transfer equation over space and angle. First, the treatment of the Monte Carlo-independent column approximation (MCICA) is modified focusing on efficiency using a reduced number of random samples ("G-packed") within a reconstructed and unified radiation package. The original McICA takes 20% of CPU time of radiation in the Global/Regional Integrated Model systems (GRIMs). The CPU time consumption of McICA is reduced by 70% without compromising accuracy. Second, parameterizations of shortwave two-stream approximations are revised to reduce errors with respect to the 16-stream discrete ordinate method. Delta-scaled two-stream approximation (TSA) is almost unanimously used in Global Circulation Model (GCM) but contains systematic errors which overestimate forward peak scattering as solar elevation decreases. These errors are alleviated by adjusting the parameterizations of each scattering element—aerosol, liquid, ice and snow cloud particles. Parameterizations are determined with 20,129 atmospheric columns of the GRIMs data and tested with 13,422 independent data columns. The result shows that the root-mean-square error (RMSE) over the all atmospheric layers is decreased by 39% on average without significant increase in computational time. Revised TSA developed and validated with a separate one-dimensional model is mounted on GRIMs for mid-term numerical weather forecasting. Monthly averaged global forecast skill scores are unchanged with revised TSA but the temperature at lower levels of the atmosphere (pressure ≥ 700 hPa) is slightly increased (< 0.5 K) with corrected atmospheric absorption.

7 CFR 58.444 - Packaging and repackaging.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Packaging and repackaging. 58.444 Section 58.444... Procedures § 58.444 Packaging and repackaging. (a) Packaging rindless cheese or cutting and repackaging all styles of bulk cheese shall be conducted under rigid sanitary conditions. The atmosphere of the packaging...

Partial hydrophilic modification of biaxially oriented polypropylene film by an atmospheric pressure plasma jet with the allylamine monomer

NASA Astrophysics Data System (ADS)

Chen, W. X.; Yu, J. S.; Hu, W.; Chen, G. L.

2016-11-01

In this paper, the partial modification of the biaxially oriented polypropylene (BOPP) film for potential biological and packaging applications was achieved via hydrophilic modification using atmospheric pressure plasma jet (APPJ). In the APPJ system, the allylamine (ALA) monomer was polymerized on the BOPP surface by either the Ar/O2 or the He/O2 plasma. The results showed that plasmatic modification created many micro/nano sized holes on the BOPP film, which increased the surface roughness dramatically and the increased roughness enhanced the combining intensity between the BOPP film and the ALA polymer. However, such a plasmatic modification increased the water vapor permeability. The FTIR and XPS characterizations showed that the amine groups were grafted onto the BOPP film, and the contact angle of the BOPP film decreases from 98.5° to 8°. Compared with the BOPP films treated by the Ar or He plasma, the barrier property of the modified BOPP film increased significantly when the ALA polymer was incorporated. The bio-affinity/toxicity of ALA polymer was illustrated by the attachment of the cultured SMMC-7721 hepatoma cells on the modified BOPP film. The significant enhancement in the cell density indicated that modified BOPP film was highly bio-compatible and non-toxic, especially treated with the Ar/O2/ALA plasma.

Radiosensitization: enhancing the radiation inactivation of foodborne bacteria

NASA Astrophysics Data System (ADS)

Borsa, J.; Lacroix, M.; Ouattara, B.; Chiasson, F.

2004-09-01

Irradiation of meat products to kill pathogens can be limited by radiation-induced detriment of sensory quality. Since such detriment is directly related to dose, one approach to reduce it is by devising means to lower the dose of radiation required for processing. Increasing the radiation sensitivity of the target microorganisms would lower the dose required for a given level of microbial kill. In this work, the radiation sensitivities of inoculated Escherichia coli and Salmonella typhi in ground beef were examined under a variety of conditions. Results showed that specific manipulations of treatment conditions significantly increased the radiation sensitivity of the test organisms, ranging from a few percent to several-fold reduction in D10. In particular, radiation sensitization could be effected by certain additives, including carvacrol, thymol and trans-cinnamaldehyde, and also by certain compositions of modified atmosphere in the package headspace. A combination of additives and modified atmosphere effected a greater radiosensitization effect than could be achieved by either factor applied alone. Radiosensitization could be demonstrated with irradiation of either fresh or frozen ground meat. The radiosensitization phenomenon may be of practical utility in enhancing the technical effectiveness and feasibility of irradiation of a variety of meat and other food products.

A novel approach for calculating shelf life of minimally processed vegetables.

PubMed

Corbo, Maria Rosaria; Del Nobile, Matteo Alessandro; Sinigaglia, Milena

2006-01-15

Shelf life of minimally processed vegetables is often calculated by using the kinetic parameters of Gompertz equation as modified by Zwietering et al. [Zwietering, M.H., Jongenburger, F.M., Roumbouts, M., van't Riet, K., 1990. Modelling of the bacterial growth curve. Applied and Environmental Microbiology 56, 1875-1881.] taking 5x10(7) CFU/g as the maximum acceptable contamination value consistent with acceptable quality of these products. As this method does not allow estimation of the standard errors of the shelf life, in this paper the modified Gompertz equation was re-parameterized to directly include the shelf life as a fitting parameter among the Gompertz parameters. Being the shelf life a fitting parameter is possible to determine its confidence interval by fitting the proposed equation to the experimental data. The goodness-of-fit of this new equation was tested by using mesophilic bacteria cell loads from different minimally processed vegetables (packaged fresh-cut lettuce, fennel and shredded carrots) that differed for some process operations or for package atmosphere. The new equation was able to describe the data well and to estimate the shelf life. The results obtained emphasize the importance of using the standard errors for the shelf life value to show significant differences among the samples.

Effect of packaging methods and crude aloe vera gel (Aloe vera barbadensis miller) on the storage quality of enrobed goat meat bites.

PubMed

Jairath, Gauri; Chatli, Manish K; Sahoo, Jhari; Biswas, Ashim K

2015-06-01

The storage stability of enrobed goat meat bites (EGMB) incorporated with 3 % crude aloe vera (AV) gel was evaluated under aerobic (T-1; unenrobed control product, T-2; enrobed AV treated product) and modified atmospheric packaging (MAP, 50:50, CO2 and N2) (T-3; unenrobed control product, T-4; enrobed AV treated product) at 4 ± 1 °C for 42 days on the basis of physico-chemical, microbiological and sensory attributes. The pH value was higher, whereas water activity (aW) was lower in enrobed and MAP product. Thiobarbituric acid reacting substances (TBARS) and free fatty acid (FFA) values were significantly (P < 0.05) lower in MAP packaged (T-3) and AV treated products (T-2 and T-4) products than aerobic packaged (T-1), however it followed an increasing trend in all the products throughout storage. Instrumental colour and textural profile attributes were better maintained in MAP products than others. The sensory panellists graded T-4 'good to very good' even on Day 42, whereas T-1 was acceptable only up to 28 days. Standard Plate Count (SPC) was significantly (P < 0.05) lower in MAP products than aerobic packaged products. Results concluded that EGMB treated with AV gel can be successfully stored more than 42 days under MAP conditions without affecting its physico-chemical, textural, microbiological and sensory attributes.

Application of Electronic Nose for Measuring Total Volatile Basic Nitrogen and Total Viable Counts in Packaged Pork During Refrigerated Storage.

PubMed

Li, Miaoyun; Wang, Haibiao; Sun, Lingxia; Zhao, Gaiming; Huang, Xianqing

2016-04-01

The objective of this study was to predict the total viable counts (TVC) and total volatile basic nitrogen (TVB-N) in pork using an electronic nose (E-nose), and to assess the freshness of chilled pork during storage using different packaging methods, including pallet packaging (PP), vacuum packaging (VP), and modified atmosphere packaging (MAP, 40% O2 /40% CO2 /20% N2 ). Principal component analysis (PCA) was used to analyze the E-nose signals, and the results showed that the relationships between the freshness of chilled pork and E-nose signals could be distinguished in the loadings plots, and the freshness of chilled pork could be distributed along 2 first principal components. Multiple linear regression (MLR) was used to correlate TVC and TVB-N to E-nose signals. High F and R2 values were obtained in the MLR output of TVB-N (F = 32.1, 21.6, and 24.2 for PP [R2 = 0.93], VP [R2 = 0.94], and MAP [R2 = 0.95], respectively) and TVC (F = 34.2, 46.4, and 7.8 for PP [R2 = 0.98], VP [R2 = 0.89], and MAP [R2 = 0.85], respectively). The results of this study suggest that it is possible to use the E-nose technology to predict TVB-N and TVC for assessing the freshness of chilled pork during storage. © 2016 Institute of Food Technologists®

Decreased dosage of acidified sodium chlorite reduces microbial contamination and maintains organoleptic qualities of ground beef products.

PubMed

Bosilevac, Joseph M; Shackelford, Steven D; Fahle, Rick; Biela, Timothy; Koohmaraie, Mohammad

2004-10-01

Acidified sodium chlorite (ASC) spray was evaluated at decreased dosages and application rates to determine its efficacy for reducing bacterial contamination on boneless beef trimmings used for production of raw ground beef products while maintaining desirable consumer qualities in the finished ground beef products. Two different applications of ASC (600 ppm applied at a rate of 1.3 oz/lb and 300 ppm applied at a rate of 1 oz/lb) were used to treat boneless beef trimmings before grinding. The effect of ASC treatment on 50/50 lean beef trimmings was greater than on 90/10 trimmings. ASC at 600 ppm reduced both the aerobic plate counts (APC) and Enterobacteriaceae counts (EBC) by 2.3 log CFU/g on 50/50 trimmings, whereas treatment with 300 ppm ASC reduced APC and EBC of 50/50 trimmings by 1.1 and 0.7 log CFU/g, respectively. Ground beef formulations of 90/10 and 73/27 were produced from the treated boneless beef trim and packaged in chubs and in modified atmosphere packaging. The efficacy of ASC spray treatment to inhibit APC and EBC over the shelf life of each ground beef product was monitored. The APC and EBC in ground beef chubs were reduced by 1.0 to 1.5 log CFU/g until day 20. The APC and EBC for products in modified atmosphere packaging were reduced 1.5 to 3.0 log CFU/g throughout their shelf life. Both decreased dosages of ASC were equally effective on 90/10 lean ground beef, but the 300 ppm ASC treatment was slightly better at reducing the EBC of 73/27 ground beef. The organoleptic qualities (color, odor, and taste) of the ground beef products treated with 300 ppm ASC were found to be superior to those treated with 600 ppm ASC. Our results indicated that decreased dosages of ASC reduce contamination and lengthen the shelf life of ground beef. Furthermore, the 300 ppm ASC treatment reduced bacterial counts while maintaining desirable organoleptic ground beef qualities.

Methods for preservation and extension of shelf life.

PubMed

Gould, G W

1996-11-01

There is potential for spoilage of all foods at some rate or other following harvest, slaughter or manufacture and spoilage may occur at any of the stages between the acquisition of raw materials and the eventual consumption of a food product. These stages include processing, packaging, distribution, retail display, transport, storage and use by the consumer. They are under varying degrees of control that aim to deliver a satisfactory shelf life, to ensure that the finally-consumed product is of high quality and to ensure that it is safe. Spoilage may be caused by a wide range of reactions including some that are essentially physical, some that are chemical, some enzymic and some microbiological. The various forms of microbiological spoilage are preventable to a large degree by a wide range of preservation techniques, most of which act by preventing or inhibiting microbial growth (e.g., chilling, freezing, drying, curing, conserving, vacuum packing, modified atmosphere packing, acidifying, fermenting and adding preservatives). A smaller number of techniques act by inactivating microorganisms (e.g., pasteurization, sterilization and irradiation). Additional techniques restrict the access of microorganisms to products (e.g., aseptic processing and packaging. A major trend is that new and emerging preservation techniques which are coming into use or are under development include more that act by inactivation (e.g., ultrahigh pressure, electroporation, manothermosonication and addition of bacteriolytic enzymes). A further trend is towards the use of procedures that deliver products that are less heavily preserved, have higher quality, are more natural, freer from additives and nutritionally healthier. Less severe preservation procedures are therefore being developed that make use of preservative factors in combinations to deliver (a) less damage to product quality (hurdle technologies); (b) new methods of heating that are better controlled and therefore deliver milder heat to products; (c) cook-chill combinations that deliver longer high quality shelf lives: (d) modified atmosphere packaging to retain quality longer; and (e) use of antimicrobial systems that are more natural. Many of the existing and emerging preservation techniques act by interfering with the homeostatic mechanisms that microorganisms have evolved in order to survive extreme environmental stresses.

Control of browning and microbial growth on fresh-cut apples by sequential treatment of sanitizers and calcium ascorbate.

PubMed

Wang, Hua; Feng, Hao; Luo, Yaguang

2007-01-01

This study investigated the efficacy of different sanitizers, including acidic electrolyzed water (AEW), peroxyacetic acid (POAA), and chlorine, on the inactivation of Escherichia coli O157:H7 on fresh-cut apples. The effects of the sanitizers and sequential treatments of AEW or POAA followed by calcium ascorbate (CaA) on browning inhibition and organoleptic qualities of fresh-cut apples stored under different package atmospheres at 4 degrees C were also evaluated. Changes in package atmosphere composition, product color, firmness, total aerobic bacterial counts, yeast and mold counts, and sensory qualities were examined at 0, 4, 8, 11, and 21 d. Among all sanitizer treatments, POAA and AEW achieved the highest reduction on E. coli O157:H7 populations. The sequential treatment of AEW followed by CaA (AEW-CaA) achieved the best overall dual control of browning and bacterial growth on fresh-cut apple wedges. Package atmospheres changed significantly over time and among package materials. Packages prepared with films having an oxygen transmission rate (OTR) of 158 had significantly lower O2 and higher CO2 partial pressures than those prepared with 225 OTR films and the Ziploc bags. The effect of package atmospheres on the browning of apples is more pronounced on AEW, POAA, and POAA-CaA-treated apple wedges than on AEW-CaA-treated samples.

Proteomic analysis to investigate color changes of chilled beef longissimus steaks held under carbon monoxide and high oxygen packaging.

PubMed

Yang, Xiaoyin; Wu, Shuang; Hopkins, David L; Liang, Rongrong; Zhu, Lixian; Zhang, Yimin; Luo, Xin

2018-08-01

This study investigated the proteome basis for color stability variations in beef steaks packaged under two modified atmosphere packaging (MAP) methods: HiOx-MAP (80% O 2 /20% CO 2 ) and CO-MAP (0.4% CO/30% CO 2 /69.6% N 2 ) during 15 days of storage. The color stability, pH, and sarcoplasmic proteome analysis of steaks were evaluated on days 0, 5, 10 and 15 of storage. Proteomic results revealed that the differential expression of the sarcoplasmic proteome during storage contributed to the variations in meat color stability between the two MAP methods. Compared with HiOx-MAP steaks, some glycolytic and energy metabolic enzymes important in NADH regeneration and antioxidant processes, antioxidant peroxiredoxins (thioredoxin-dependent peroxide reductase, peroxiredoxin-2, peroxiredoxin-6) and protein DJ-1 were more abundant in CO-MAP steaks. The over-expression of these proteins could induce CO-MAP steaks to maintain high levels of metmyoglobin reducing activity and oxygen consumption rate, resulting in CO-MAP steaks exhibiting better color stability than HiOx-MAP steaks during storage. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effective preservation techniques to prolong the shelf life of ready-to-eat oysters.

PubMed

Costa, Cristina; Conte, Amalia; Del Nobile, Matteo Alessandro

2014-10-01

Oysters have a high commercial value but owing to their short shelf life are generally commercialized as raw material within very restricted market borders. A step-by-step optimization approach was used in this work to design ready-to-eat oyster packaging. In particular, six different steps were carried out in order to extend their shelf life. The concentration of sodium alginate to realize a coating that was effective in terms of easy peeling and ability in preventing product dehydration was optimized. Coated oysters were packaged under different modified atmosphere (MAP) conditions to find the best MAP. Subsequently, to further promote product preservation, sodium acetate was selected as an effective antimicrobial agent to be applied by dipping treatment prior to coating. All preservation strategies singly tested were finally combined to assess the shelf life prolongation of ready-to-eat oysters. Dipping in sodium acetate (10 g L⁻¹), coating with sodium alginate (40 g L⁻¹) and packaging under MAP (0:75 O₂:CO₂) represent the best conditions to guarantee a significant shelf life extension to about 160 h compared with 57 h for unpackaged oysters. © 2014 Society of Chemical Industry.

In-Package atmospheric cold plasma treatment of bulk grape tomatoes for their microbiological safety and preservation

USDA-ARS?s Scientific Manuscript database

Effects of dielectric barrier discharge atmospheric cold plasma (DACP) treatment on the inactivation of Salmonella and the storability of grape tomato were investigated. Grape tomatoes, with or without inoculation with Salmonella, were packaged in a polyethylene terephthalate (PET) commercial clamsh...

Understanding critical factors for the quality and shelf-life of MAP fresh meat: a review.

PubMed

Singh, Preeti; Wani, Ali Abas; Saengerlaub, Sven; Langowski, Horst-Christian

2011-02-01

Due to increased demands for greater stringency in relation to hygiene and safety issues associated with fresh food products, coupled with ever-increasing demands by retailers for cost-effective extensions to product shelf-lives and the requirement to meet consumer expectations in relation to convenience and quality, the food packaging industry has rapidly developed to meet and satisfy expectations. One of the areas of research that has shown promise, and had success, is modified atmosphere packaging (MAP). The success of MAP-fresh meat depends on many factors including good initial product quality, good hygiene from the source plants, correct packaging material selection, the appropriate gas mix for the product, reliable packaging equipment, and maintenance of controlled temperatures and humidity levels. Advances in plastic materials and equipment have propelled advances in MAP, but other technological and logistical considerations are needed for successful MAP systems for raw chilled meat. Although several parameters critical for the quality of MA packed meat have been studied and each found to be crucial, understanding of the interactions between the parameters is needed. This review was undertaken to present the most comprehensive and current overview of the widely available, scattered information about the various integrated critical factors responsible for the quality and shelf life of MA packed meat with an interest to stimulate further research to optimize different quality parameters.

Calcium lactate effect on the shelf life of osmotically dehydrated guavas.

PubMed

Pereira, Leila M; Carmello-Guerreiro, Sandra M; Junqueira, Valéria C A; Ferrari, Cristhiane C; Hubinger, Miriam D

2010-01-01

The effect of calcium lactate on osmodehydrated guavas in sucrose and maltose solutions was monitored during storage under passive modified atmosphere for 24 d at 5 °C. Sample texture and color characteristics, microbial spoilage, sensory acceptance, structural changes, and gas composition inside the packages were periodically evaluated. Calcium lactate inhibited microbial growth on guavas, with yeast and mold counts in the order of 10(2) CFU/g throughout storage. The calcium salt reduced respiration rate of guava products, showing O(2) and CO(2) concentrations around 18% and 3% inside the packages. A firming effect on fruit texture, with up to 5 and 2 times higher stress and strain at failure values and tissue structure preservation could also be attributed to calcium lactate use. However, fruits treated with calcium lactate, osmodehydrated in maltose and sucrose solutions, showed sensory acceptance scores below the acceptability limit (4.5) after 13 and 17 d of storage, respectively. © 2010 Institute of Food Technologists®

The effect of carbon dioxide on the shelf life of ready-to-eat shredded chicken breast stored under refrigeration.

PubMed

Rodriguez, M B R; Junior, C A Conte; Carneiro, C S; Franco, R M; Mano, S B

2014-01-01

The objective of the present study was to determine the shelf life of ready-to-eat cooked chicken breast fillets (shredded) stored in atmospheres that were modified with different concentrations of CO2 and to establish a relationship between the concentration of this gas and bacterial growth. The samples were divided into 7 groups with different packaging conditions: aerobiosis, vacuum, and 10, 30, 50, 70, and 90% CO2 (with the remaining volume filled with N2). All of the samples were stored at 4 ± 2°C for 28 d. During this period, pH tests and counts of aerobic heterotrophic mesophyll bacteria (AHMB), aerobic heterotrophic psychotropic bacteria (AHPB), Enterobacteriaceae, and lactic acid bacteria (LAB) were performed, and the gas compositions of the packaging atmospheres were verified. The pH of the aerobic packages increased during storage. However, the other treatments resulted in the opposite trend, with the CO2 concentration decreasing over the first 24 h and then remaining constant until the end of experiment. A gradual increase in the AHMB, AHPB, Enterobacteriaceae, and LAB counts was observed during storage; this increase was faster in the meat that was packed under aerobiosis conditions than in the other treatments. The treatments with a CO2 concentration above 10% exhibited lower Enterobacteriaceae growth, whereas LAB growth was discrete in all of the treatments, independent of the CO2 concentration. The shelf life of the samples packed with 90% CO2 was 28 d. Based on the AHMB and AHPB counts, the shelf life was 3 times longer than for the samples packed under aerobiosis conditions (9 d). The increased package CO2 concentration caused a reduction in the growth rate of the examined bacteria (r = 0.99), and treatment with 90% CO2 appears promising as a method with which to increase the product's shelf life.

The study of aerosol and ozone measurements in lower boundary layer with UAV helicopter platform

NASA Astrophysics Data System (ADS)

Lin, Po-hsiung; Chen, Wen-nai

2013-04-01

This study describes the aerosol and ozone measurement in the lower atmospheric boundary layer of highly polluted region at Kao-hsiung, Taiwan with a small unmanned aerial vehicle (UAV) helicopter platform. This UAV helicopter, modified from Gaui-X7 electronic-power model helicopter with autopilot AHRS (Altitude-Head-Reference System) kit, has fast climb speed up to 700 m height and keeps stable status for atmospheric measurements in five-minute fly leg. Several quick-replaced battery packages are ready on ground for field intensive observation. The payload rack under this UAV helicopter carries a micro-Aethalometer (black carbon concentration), ozone meter, temperature-humidity sensor, barometer and a time-lapse digital camera. The field measurement site closes to Linyuan Petrochemical Industrial Park, where is one of the heavy polluted regions in Taiwan. Balloon-borne Vaisala RS-92 radiosonde and CL31 Lidar Ceilometer are used to provide the background of the atmosphere at the same time. More data analysis measured by UAV helicopter and its potential application will be discussed.

The Unmanned Aerial System SUMO: an alternative measurement tool for polar boundary layer studies

NASA Astrophysics Data System (ADS)

Mayer, S.; Jonassen, M. O.; Reuder, J.

2012-04-01

Numerical weather prediction and climate models face special challenges in particular in the commonly stable conditions in the high-latitude environment. For process studies as well as for model validation purposes in-situ observations in the atmospheric boundary layer are highly required, but difficult to retrieve. We introduce a new measurement system for corresponding observations. The Small Unmanned Meteorological Observer SUMO consists of a small and light-weight auto-piloted model aircraft, equipped with a meteorological sensor package. SUMO has been operated in polar environments, among others during IPY on Spitsbergen in the year 2009 and has proven its capabilities for atmospheric measurements with high spatial and temporal resolution even at temperatures of -30 deg C. A comparison of the SUMO data with radiosondes and tethered balloons shows that SUMO can provide atmospheric profiles with comparable quality to those well-established systems. Its high data quality allowed its utilization for evaluation purposes of high-resolution model runs performed with the Weather Research and Forecasting model WRF and for the detailed investigation of an orographically modified flow during a case study.

Effect of different film packaging on microbial growth in minimally processed cactus pear (Opuntia ficus-indica).

PubMed

Palma, A; Mangia, N P; Fadda, A; Barberis, A; Schirra, M; D'Aquino, S

2013-01-01

Microorganisms are natural contaminants of fresh produce and minimally processed products, and contamination arises from a number of sources, including the environment, postharvest handling and processing. Fresh-cut products are particularly susceptible to microbial contaminations because of the changes occurring in the tissues during processing. In package gas composition of modified atmosphere packaging (MAP) in combination with low storage temperatures besides reducing physiological activity of packaged produce, can also delay pathogen growth. Present study investigated on the effect of MAPs, achieved with different plastic films, on microbial growth of minimally processed cactus pear (Opuntio ficus-indica) fruit. Five different plastic materials were used for packaging the manually peeled fruit. That is: a) polypropylene film (Termoplast MY 40 micron thickness, O2 transmission rate 300 cc/m2/24h); b) polyethylene film (Bolphane BHE, 11 micron thickness, O2 transmission rate 19000 cc/m2/24h); c) polypropylene laser-perforated films (Mach Packaging) with 8, 16 or 32 100-micron holes. Total aerobic psychrophilic, mesophilic microorganisms, Enterobacteriaceae, yeast, mould populations and in-package CO2, O2 and C2H4 were determined at each storage time. Different final gas compositions, ranging from 7.8 KPa to 17.1 KPa O2, and 12.7 KPa to 2.6 KPa CO2, were achieved with MY and micro perforated films, respectively. Differences were detected in the mesophilic, Enterobacteriaceae and yeast loads, while no difference was detected in psychrophilic microorganisms. At the end of storage, microbial load in fruits sealed with MY film was significantly lower than in those sealed with BHE and micro perforated films. Furthermore, fruits packed with micro-perforated films showed the highest microbial load. This occurrence may in part be related to in-package gas composition and in part to a continuous contamination of microorganisms through micro-holes.

Disinfection of fresh chicken breast fillets with in-package atmospheric cold plasma: effect of treatment voltage and time

USDA-ARS?s Scientific Manuscript database

Effects of treatment voltage and time of in-package atmospheric cold plasma (ACP) were studied on ozone formation, microbiological quality, surface color, and pH of fresh chicken fillets. Samples were sealed in food trays in air, treated with a dielectric-barrier-discharge (DBD) ACP system, and stor...

Shelf-life of a chilled precooked chicken product stored in air and under modified atmospheres: microbiological, chemical, sensory attributes.

PubMed

Patsias, A; Chouliara, I; Badeka, A; Savvaidis, I N; Kontominas, M G

2006-08-01

This study evaluated the effect of modified atmosphere packaging on shelf-life extension of a precooked chicken meat product stored at 4 degrees C using microbiological, physico-chemical and sensory analyses. The following gas mixtures were used: M1: 30%/70% (CO2/N2), M2: 60%/40% (CO2/N2) and M3: 90%/10% (CO2/N2). Identical chicken samples were aerobically packaged and used as control samples. Sampling was carried out at predetermined time intervals namely: 0, 4, 8, 12, 16 and 20 days. Total viable counts (TVC), Lactic acid bacteria (LAB), Brochothrix thermosphacta, pseudomonads, yeasts and molds, and Enterobacteriaceae were monitored. TVC of precooked chicken product reached 7 log cfu/g, after days 12 and 16 of storage (air and M1 samples), respectively. The M2 and M3 gas mixture packaged samples did not reach this value throughout the 20 days storage period under refrigeration. LAB and to a lesser degree B. thermosphacta, constituted part of the natural microflora of precooked chicken samples stored in air and under MAP reaching 7.0-8.1 log cfu/g at the end of storage period. Of the remaining bacterial species monitored, both pseudomonads and yeasts/molds were significantly higher (P<0.05) for chicken samples stored in air than under MAP (M1, M2, M3) throughout the entire storage period under refrigeration. Finally, counts of Enterobacteriaceae were low (<2 log cfu/g) in all chicken samples irrespective of the packaging conditions throughout the entire storage period. Of the chemical indices determined, thiobarbituric (TBA) values in all cases remained low, equal or lower than 3.0 mg malonaldehyde (MA)/kg during the entire storage period. Results of the present work show that the limit of sensory acceptability was only reached for the aerobically stored and M1 gas mixture chicken samples somewhat before days 16 and 20 of storage, respectively. This limit coincided with high TVC and LAB populations (>6.8 log cfu/g), increased lipid oxidation (aerobic storage only) and apparent growth of yeasts/moulds on the surface of chicken samples. The use of MAP as shown in the present study, resulted in an extension of shelf-life of precooked chicken by ca. 4 days (M1 gas mixture), and by more than 6 days (M2 and M3 gas mixtures), respectively. Precooked chicken meat was better preserved under M2 and M3 mixtures maintaining desirable odor/taste attributes even on final day of storage tested.

TMAP: Tübingen NLTE Model-Atmosphere Package

NASA Astrophysics Data System (ADS)

Werner, Klaus; Dreizler, Stefan; Rauch, Thomas

2012-12-01

The Tübingen NLTE Model-Atmosphere Package (TMAP) is a tool to calculate stellar atmospheres in spherical or plane-parallel geometry in hydrostatic and radiative equilibrium allowing departures from local thermodynamic equilibrium (LTE) for the population of atomic levels. It is based on the Accelerated Lambda Iteration (ALI) method and is able to account for line blanketing by metals. All elements from hydrogen to nickel may be included in the calculation with model atoms which are tailored for the aims of the user.

Characterization of the Aerosol Instrument Package for the In-service Aircraft Global Observing System IAGOS

NASA Astrophysics Data System (ADS)

Bundke, Ulrich; Berg, Marcel; Tettig, Frank; Franke, Harald; Petzold, Andreas

2015-04-01

The atmospheric aerosol influences the climate twofold via the direct interaction with solar radiation and indirectly effecting microphysical properties of clouds. The latter has the largest uncertainty according to the last IPPC Report. A measured in situ climatology of the aerosol microphysical properties is needed to reduce the reported uncertainty of the aerosol climate impact. The European Research Infrastructure IAGOS (In-service Aircraft for a Global Observing System; www.iagos.org) responds to the increasing requests for long-term, routine in situ observational data by using commercial passenger aircraft as measurement platform. However, scientific instrumentation for the measurement of atmospheric constituents requires major modifications before being deployable aboard in-service passenger aircraft. The IAGOS Aerosol Package (IAGOS-P2C) consists of two modified Butanol based CPCs (Model Grimm 5.410) and one optical particle counter (Model Grimm Sky OPC 1.129). A thermodenuder at 250°C is placed upstream the second CPC, thus the number concentrations of the total aerosol and the non-volatile aerosol fraction is measured. The Sky OPC measures the size distribution in the rage theoretically up to 32 μ m. Because of the inlet cut off diameter of D50=3 μ m we are using the 16 channel mode in the range of 250 nm - 2.5 μ m at 1 Hz resolution. In this presentation the IAGOS Aerosol package is characterized for pressure levels relevant for the planned application, down to cruising level of 150 hPa including the inlet system. In our aerosol lab we have tested the system against standard instrumentation with different aerosol test substances in a long duration test. Particle losses are characterized for the inlet system. In addition first results for airborne measurements are shown from a first field campaign.

CFD modeling to improve safe and efficient distribution of chlorine dioxide gas for packaging fresh produce

USDA-ARS?s Scientific Manuscript database

The efficiency of the packaging system in inactivating food borne pathogens and prolonging the shelf life of fresh-cut produce is influenced by the design of the package apart from material and atmospheric conditions. Three different designs were considered to determine a specific package design ens...

The effects of atmospheric pressure cold plasma treatment on microbiological, physical-chemical and sensory characteristics of vacuum packaged beef loin.

PubMed

Bauer, A; Ni, Y; Bauer, S; Paulsen, P; Modic, M; Walsh, J L; Smulders, F J M

2017-06-01

Effects on vacuum packaged and non-packaged beef longissimus samples exposed to atmospheric cold plasma (ACP) generated at different powers were studied over a 10day period of vacuum-, and a subsequent 3day period of aerobic storage. Exposure of non-covered beef samples under high power ACP conditions resulted in increased a*, b*, Chroma and Hue values, but ACP treatment of packaged loins did not impact colour (L*, a*, b*, Chroma, Hue), lipid peroxidation, sarcoplasmic protein denaturation, nitrate/nitrite uptake, or myoglobin isoform distribution. Colour values measured after 3days of aerobic storage following unpackaging (i.e. 20days post-mortem) were similar and all compliant with consumer acceptability standards. Exposure to ACP of the polyamide-polyethylene packaging film inoculated with Staphylococcus aureus, Listeria monocytogenes and two Escherichia coli strains resulted in >2 log reduction without affecting the integrity of the packaging matrix. Results indicate that ACP can reduce microbial numbers on surfaces of beef packages without affecting characteristics of the packaged beef. Copyright © 2017 Elsevier Ltd. All rights reserved.

Inactivation of Escherichia coli 0157:H7 and aerobic microorganisms in Romaine lettuce packaged in a commercial polyethylene terephthalate container using atmospheric cold plasma

USDA-ARS?s Scientific Manuscript database

The effects of dielectric barrier discharge atmospheric cold plasma (DACP) treatment on the inactivation of Escherichia coli O157:H7 and aerobic microorganisms in Romaine lettuce packaged in a conventional commercial plastic container were evaluated during storage at 4 degrees C for 7 days. Effects ...

Antimicrobial activity of biodegradable polysaccharide and protein-based films containing active agents.

PubMed

Kuorwel, Kuorwel K; Cran, Marlene J; Sonneveld, Kees; Miltz, Joseph; Bigger, Stephen W

2011-04-01

Significant interest has emerged in the introduction of food packaging materials manufactured from biodegradable polymers that have the potential to reduce the environmental impacts associated with conventional packaging materials. Current technologies in active packaging enable effective antimicrobial (AM) packaging films to be prepared from biodegradable materials that have been modified and/or blended with different compatible materials and/or plasticisers. A wide range of AM films prepared from modified biodegradable materials have the potential to be used for packaging of various food products. This review examines biodegradable polymers derived from polysaccharides and protein-based materials for their potential use in packaging systems designed for the protection of food products from microbial contamination. A comprehensive table that systematically analyses and categorizes much of the current literature in this area is included in the review.

NOAA's Van-Based Mobile Atmospheric Emissions Measurement Laboratory

NASA Astrophysics Data System (ADS)

Dube, W. P.; Peischl, J.; Neuman, J. A.; Eilerman, S. J.; Holloway, M.; Roberts, O.; Aikin, K. C.; Ryerson, T. B.

2015-12-01

The Chemical Science Division (CSD) mobile atmospheric emissions measurement laboratory is the second and latest of two mobile measurement vans outfitted for atmospheric sampling by the NOAA Earth System Research Laboratory. In this presentation we will describe the modifications made to this vehicle to provide a versatile and relatively inexpensive instrument platform including: the 2 kW 120 volt instrument power system; battery back-up system; data acquisition system; real-time display; meteorological, directional, and position sensor package; and the typical atmospheric emissions instrument package. The van conversion uses commercially available, off-the-shelf components from the marine and RV industries, thus keeping the costs quite modest.

Efficacy of Pseudomonas graminis CPA-7 against Salmonella spp. and Listeria monocytogenes on fresh-cut pear and setting up of the conditions for its commercial application.

PubMed

Iglesias, M B; Abadias, M; Anguera, M; Viñas, I

2018-04-01

Pseudomonas graminis CPA-7 has been reported to control foodborne pathogens on fresh-cut apple, peach and melon. The first aim of this study was to assess its antagonistic activity against Salmonella spp. and L. monocytogenes on fresh-cut pear. CPA-7 was able to control both pathogens on fresh-cut pear stored in air conditions at 5, 10 and 20 °C. However, when CPA-7 antagonistic effect was tested by simulating commercial application (with antioxidant solution and passive modified atmosphere packaging), its effect decreased and no reductions of foodborne pathogens were reported at 10 °C. Therefore, the second aim was to optimise the antioxidant solution and the packaging in order to retain its antagonistic capacity. The selected antioxidant solution was 2% ascorbic acid +2% sodium citrate +1% CaCl 2 according to growth and effect of CPA-7. Film permeability, which affects gas composition inside fruit packages, influenced CPA-7 efficacy. If the biopreservative strain is used, film has to be sufficiently gas permeable to allow CPA-7 function and at the same time to maintain product quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

Radiative transfer modeling through terrestrial atmosphere and ocean accounting for inelastic processes: Software package SCIATRAN

NASA Astrophysics Data System (ADS)

Rozanov, V. V.; Dinter, T.; Rozanov, A. V.; Wolanin, A.; Bracher, A.; Burrows, J. P.

2017-06-01

SCIATRAN is a comprehensive software package which is designed to model radiative transfer processes in the terrestrial atmosphere and ocean in the spectral range from the ultraviolet to the thermal infrared (0.18-40 μm). It accounts for multiple scattering processes, polarization, thermal emission and ocean-atmosphere coupling. The main goal of this paper is to present a recently developed version of SCIATRAN which takes into account accurately inelastic radiative processes in both the atmosphere and the ocean. In the scalar version of the coupled ocean-atmosphere radiative transfer solver presented by Rozanov et al. [61] we have implemented the simulation of the rotational Raman scattering, vibrational Raman scattering, chlorophyll and colored dissolved organic matter fluorescence. In this paper we discuss and explain the numerical methods used in SCIATRAN to solve the scalar radiative transfer equation including trans-spectral processes, and demonstrate how some selected radiative transfer problems are solved using the SCIATRAN package. In addition we present selected comparisons of SCIATRAN simulations with those published benchmark results, independent radiative transfer models, and various measurements from satellite, ground-based, and ship-borne instruments. The extended SCIATRAN software package along with a detailed User's Guide is made available for scientists and students, who are undertaking their own research typically at universities, via the web page of the Institute of Environmental Physics (IUP), University of Bremen: http://www.iup.physik.uni-bremen.de.

Carbon Monoxide in Meat and Fish Packaging: Advantages and Limits

PubMed Central

Roncalés, Pedro

2018-01-01

Due to increased demands for greater expectation in relation to quality, convenience, safety and extended shelf-life, combined with growing demand from retailers for cost-effective extensions of fresh muscle foods’ shelf-life, the food packaging industry quickly developed to meet these expectations. During the last few decades, modified atmosphere packaging (MAP) of foods has been a promising area of research, but much remains to be known regarding the use of unconventional gases such carbon monoxide (CO). The use of CO for meat and seafood packaging is not allowed in most countries due to the potential toxic effect, and its use is controversial in some countries. The commercial application of CO in food packaging was not then considered feasible because of possible environmental hazards for workers. CO has previously been reported to mask muscle foods’ spoilage, and this was the primary concern raised for the prohibition, as this may mislead consumers. This review was undertaken to present the most comprehensive and current overview of the widely-available, scattered information about the use of CO in the preservation of muscle foods. The advantages of CO and its industrial limits are presented and discussed. The most recent literature on the consumer safety issues related to the use of CO and consumer acceptance of CO especially in meat packaging systems were also discussed. Recommendations and future prospects were addressed for food industries, consumers and regulators on what would be a “best practice” in the use of CO in food packaging. All this promotes high ethical standards in commercial communications by means of effective regulation, for the benefit of consumers and businesses in the world, and this implies that industrialized countries and members of their regulatory agencies must develop a coherent and robust systems of regulation and control that can respond effectively to new challenges. PMID:29360803

Survival and growth of Listeria monocytogenes and enterohemorrhagic Escherichia coli O157:H7 in minimally processed artichokes.

PubMed

Sanz, Susana; Giménez, Mercedes; Olarte, Carmen

2003-12-01

The ability of Listeria monocytogenes and Escherichia coli O157:H7 inoculated by immersion (at 4.6 and 5.5 log CFU/ g, respectively) to survive on artichokes during various stages of preparation was determined. Peeling, cutting, and disinfecting operations (immersion in 50 ppm of a free chlorine solution at 4 degrees C for 5 min) reduced populations of L. monocytogenes and E. coli O157:H7 by only 1.6 and 0.8 log units, respectively. An organic acid rinse (0.02% citric acid and 0.2% ascorbic acid) was more effective than a tap water rinse in removing these pathogens. Given the possibility of both pathogens being present on artichokes at the packaging stage, their behavior during the storage of minimally processed artichokes was investigated. For this purpose, batches of artichokes inoculated with L. monocytogenes or E. coli O157:H7 (at 5.5 and 5.2 log CFU/g, respectively) were packaged in P-Plus film bags and stored at 4 degrees C for 16 days. During this period, the equilibrium atmosphere composition and natural background microflora (mesophiles, psychrotrophs, anaerobes, and fecal coliforms) were also analyzed. For the two studied pathogens, the inoculum did not have any effect on the final atmospheric composition (10% O2, 13% CO2) or on the survival of the natural background microflora of the artichokes. L. monocytogenes was able to survive during the entire storage period in the inoculated batches, while the E. coli O157:H7 level increased by 1.5 log units in the inoculated batch during the storage period. The modified atmosphere was unable to control the behavior of either pathogen.

The combined efficacy of carvacrol and modified atmosphere packaging on the survival of Salmonella, Campylobacter jejuni and lactic acid bacteria on turkey breast cutlets.

PubMed

Nair, Divek V T; Kiess, Aaron; Nannapaneni, Rama; Schilling, Wes; Sharma, Chander Shekhar

2015-08-01

The primary objective of this study was to determine the efficacy of carvacrol in combination with modified atmosphere packaging (MAP) in reducing Salmonella on turkey breast cutlets stored at 4 °C. In experiment I, carvacrol (0.5, 1, and 2% v/v) was applied as surface treatment and samples were stored under aerobic condition or as surface and dip treatments followed by storage in an environment of 100% carbon dioxide. The findings of the experiment I revealed the synergistic activity of carvacrol with carbon dioxide in reducing Salmonella when used as dip treatment compared to the surface treatment. In experiment II, turkey breast cutlets were dip treated with carvacrol (0.25, 0.5, and 1% v/v) for 30 s and stored under MAP (95% carbon dioxide and 5% oxygen) to evaluate the efficacy against Salmonella, Campylobacter jejuni and lactic acid bacteria on turkey breast cutlets. In experiment II, the combined application of carvacrol and MAP resulted in 1.0-2.0 log CFU/g reduction (P ≤ 0.05) of both Salmonella and Campylobacter on turkey breast cutlets for 7 d storage at 4 °C. MAP alone and in combination with carvacrol reduced lactic acid bacteria (P ≤ 0.05) on cutlets stored at 4 °C for 21 d period. There was no difference (P ≤ 0.05) in meat color among treatments and controls except for an increased paleness of meat (P ≤ 0.05) observed for the 1% carvacrol treated cutlets stored under MAP after 21 d of storage. The high concentration of carbon dioxide and carvacrol treatments did not cause any alteration in meat pH (P ≤ 0.05). In conclusion, carvacrol was effective at a low concentration of 0.25% (v/v) in reducing Salmonella and C. jejuni by ∼1.0 log CFU/g when stored under MAP. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of different modified atmospheric packaging (MAP) gaseous combinations on Campylobacter and the shelf-life of chilled poultry fillets.

PubMed

Meredith, H; Valdramidis, V; Rotabakk, B T; Sivertsvik, M; McDowell, D; Bolton, D J

2014-12-01

Studies were undertaken to investigate the effect of different modified atmospheric packaging (MAP) gaseous combinations on Campylobacter and the natural microflora on poultry fillets. Skinless chicken fillets were stored in gaseous mixtures of 10%, 30%, 50%, 70% and 90% CO2 balanced with N2, 80:20% O2:N2 and 40:30:30% CO2:O2:N2 and control conditions (air) at 2 °C. Samples were analysed periodically for (previously inoculated) Campylobacter, total viable counts (TVC) (mesophiles), TVC (psychrophiles), Enterobacteriaceae, Pseudomonas and lactic acid bacteria (LAB) over 17 days of storage. The carbon dioxide solubility was determined by monitoring the changes in the headspace volume over time using a buoyancy technique and performing calculations based on volumetric measurements and the Henry's constant. Henry's constant was also used to estimate the oxygen solubility in the chicken fillets. The presence of O2 in the MAP gaseous mixtures increased the rate of Campylobacter decline on poultry fillets but in general the counts obtained in aerobic versus anaerobic packs were not significantly (P > 0.05) different. CO2 inhibited the growth of TVC, TEC, LAB and Pseudomonas but only at MAP gaseous combinations containing 50-90% CO2 where concentrations of up to 2000 ppm CO2 were recorded in the fillets after 5 days. Under these conditions a shelf-life in excess of 17 days at 2 °C was obtained. Although, dissolved O2, at levels of 33 ppm in 80:20% O2:N2 packs after 3 days, reduced Campylobacter, it also favoured the growth of the other microbes on the chicken. The optimum gaseous mixture for achieving the combined objectives of reducing Campylobacter and extending shelf was therefore 40:30:30 CO2:O2:N2, which achieved a shelf-life in excess of 14 days. Copyright © 2014 Elsevier Ltd. All rights reserved.

Balloon-Borne Full-Column Greenhouse Gas Profiling Field Campaign Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fischer, Marc L

The vertical distributions of CO2, CH4, and other gases provide important constraints for the determination of terrestrial and ocean sources and sinks of carbon and other biogeochemical processes in the Earth system. The DOE Biological and Environmental Research Program (DOE-BER) and the NOAA Earth System Research Laboratory (NOAA-ESRL) collaborate to quantify the vertically resolved distribution of atmospheric carbon-cycle gases (CO2, and CH4) within approximately 99% of the atmospheric column at the DOE ARM Southern Great Plains Facility in Oklahoma. In 2015, flights were delayed while research at NOAA focused on evaluating sources of systematic errors in the gas collection andmore » analysis system and modifying the sampling system to provide duplicate air samples in a single flight package. In 2017, we look forward to proposing additional sampling and analysis at ARM-SGP (and other sites) that characterize the vertical distribution of CO2 and CH4 over time and space.« less

Detecting small holes in packages

DOEpatents

Kronberg, James W.; Cadieux, James R.

1996-01-01

A package containing a tracer gas, and a method for determining the presence of a hole in the package by sensing the presence of the gas outside the package. The preferred tracer gas, especially for food packaging, is sulfur hexafluoride. A quantity of the gas is added to the package and the package is closed. The concentration of the gas in the atmosphere outside the package is measured and compared to a predetermined value of the concentration of the gas in the absence of the package. A measured concentration greater than the predetermined value indicates the presence of a hole in the package. Measuring may be done in a chamber having a lower pressure than that in the package.

21 CFR 178.3520 - Industrial starch-modified.

Code of Federal Regulations, 2011 CFR

2011-04-01

..., packing, processing, preparing, treating, packaging, transporting, or holding food, subject to the... and paperboard intended for food packaging. β-Diethylaminoethyl chloride hydrochloride, not to exceed... and paperboard intended for food packaging. 2,3-Epoxypropyltrimethylammonium chloride, not to exceed 5...

21 CFR 178.3520 - Industrial starch-modified.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., packing, processing, preparing, treating, packaging, transporting, or holding food, subject to the... and paperboard intended for food packaging. β-Diethylaminoethyl chloride hydrochloride, not to exceed... and paperboard intended for food packaging. 2,3-Epoxypropyltrimethylammonium chloride, not to exceed 5...

Growth and toxin production by Clostridium botulinum in steamed rice aseptically packed under modified atmosphere.

PubMed

Kasai, Yoshiaki; Kimura, Bon; Kawasaki, Susumu; Fukaya, Tetsuya; Sakuma, Kinya; Fujii, Tateo

2005-05-01

Sales and consumption of ready-to-eat aseptic steamed rice products have increased manyfold in Japan over the past 10 years. To determine the safety of steamed rice (water content 60%, pH 6.5) aseptically packaged under modified atmosphere, challenge studies were performed using a mixture of Clostridium botulinum proteolytic strains (five strains of type A and five strains of type B). Atmospheric conditions of 0 and 15% oxygen (with 5% CO2 and 5% N2 as the balance) were used. No neurotoxins were detected, and organoleptically acceptable conditions persisted for 24 weeks at 15% oxygen conditions. However, botulinum neurotoxin was found in one of three samples at 12 weeks and in one of two samples at 24 weeks at 0% oxygen and 30 degrees C. When samples were inoculated with C. botulinum with amylase (0% oxygen), neurotoxin and sample spoilage was detected after only 1 week of storage. Challenge studies using proteolytic strains of C. botulinum mixed with Bacillus subtilis (amylase formers) also were performed with atmosphere conditions of oxygen at 0, 5, 10, and 15% (with 5% CO2 and 5% N2 as the balance). Under 10 and 15% oxygen conditions, neurotoxin was not detected after 1 week of storage, but sample spoilage was detected after the same period. Under 0% oxygen conditions, neurotoxin was detected at 1 week, but the sample remained organoleptically acceptable even after 2 weeks of storage. Both neurotoxin and sample spoilage were detected at 1 week of storage under 5% oxygen conditions. Based on these results, cocontamination of amylase-producing Bacillus with C. botulinum would increase the risk of foodborne botulism when aseptic rice samples are packed under low-oxygen conditions (<5%). Therefore, to ensure the safety of these products, packing under atmospheric containing more than 10% oxygen is recommended.

Synergistic Effect of Sodium Chlorite and Edible Coating on Quality Maintenance of Minimally Processed Citrus grandis under Passive and Active MAP.

PubMed

Ban, Zhaojun; Feng, Jianhua; Wei, Wenwen; Yang, Xiangzheng; Li, Jilan; Guan, Junfeng; Li, Jiang

2015-08-01

Edible coating has been an innovation within the bioactive packaging concept. The comparative analysis upon the effect of edible coating, sodium chlorite (SC) and their combined application on quality maintenance of minimally processed pomelo (Citrus grandis) fruits during storage at 4 °C was conducted. Results showed that the combination of edible coating and SC dipping delayed the microbial development whereas the sole coating or dipping treatment was less efficient. The synergetic application of edible coating and SC treatment under modified atmosphere packaging (MAP, 10% O2 , 10% CO2 ) was able to maintain the total soluble solids level and ascorbic acid content, while reduce the weight loss as well as development of mesophiles and psychrotrophs. Nonetheless, the N, O-carboxymethyl chitosan solely coated samples showed significantly higher level of weight loss during storage with comparison to the untreated sample. Furthermore, the combined application of edible coating and SC dipping under active MAP best maintained the sensory quality of minimally processed pomelo fruit during storage. © 2015 Institute of Food Technologists®

SeaShark and Starfish opertional data processing schemes for AVHRR and SeaWiFs

NASA Astrophysics Data System (ADS)

Flowerdew, R. J.; Corlyon, Anaa M.; Greer, W. A. D.; Newby, Steve J.; Winder, C. P.

1997-02-01

SeaShark is an operational software package for processing, archiving and cataloguing AVHRR and SeaWiFS data using an operator friendly GUI. Upon receipt of a customer order, it produces standard AVHRR data products, including Sea Surface Temperature (SST) and it has recently been modified to include SeaWiFS level 2 data processing. This uses an atmospheric correction scheme developed by the Plymouth Marine Laboratory, UK (PML) that builds upon the standard Gordon and Wang approach to be applicable over both case 1 and case 2 waters. Higher level products are then generated using PML algorithms, including chlorophyll a, a CZCS-type pigment, Kd, and suspended particulate matter. Outputs are in CEOS-compatible format. The software also produces fast delivery products (FDPs) of chlorophyll a and SST. These FDPs are combined in the StarFish software package to provide maps indicating potential location of phytoplankton and the preferred thermal environment of certain pelagic fish species. Fishing vessels may obtain these maps over Inmarsat, allowing them to achieve a greater efficiency hence lower cost.

Tools for DIY site-testing

NASA Astrophysics Data System (ADS)

Flores, Federico; Rondanelli, Roberto; Abarca, Accel; Diaz, Marcos; Querel, Richard

2012-09-01

Our group has designed, sourced and constructed a radiosonde/ground-station pair using inexpensive opensource hardware. Based on the Arduino platform, the easy to build radiosonde allows the atmospheric science community to test and deploy instrumentation packages that can be fully customized to their individual sensing requirements. This sensing/transmitter package has been successfully deployed on a tethered-balloon, a weather balloon, a UAV airplane, and is currently being integrated into a UAV quadcopter and a student-built rocket. In this paper, the system, field measurements and potential applications will be described. As will the science drivers of having full control and open access to a measurement system in an age when commercial solutions have become popular but are restrictive in terms of proprietary sensor specifications, "black-box" calibration operations or data handling routines, etc. The ability to modify and experiment with both the hardware and software tools is an essential part of the scientific process. Without an understanding of the intrinsic biases or limitations in your instruments and system, it becomes difficult to improve them or advance the knowledge in any given field.

Plasma-induced polymerization for enhancing paper hydrophobicity.

PubMed

Song, Zhaoping; Tang, Jiebin; Li, Junrong; Xiao, Huining

2013-01-30

Hydrophobic modification of cellulose fibers was conducted via plasma-induced polymerization in an attempt to graft the hydrophobic polymer chains on paper surface, this increasing the hydrophobicity of paper. Two hydrophobic monomers, butyl acrylate (BA) and 2-ethylhexyl acrylate (2-EHA), were grafted on cellulose fibers, induced by atmospheric cold plasma. Various influencing factors associated with the plasma-induced grafting were investigated. Contact-angle measurement, Fourier Transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were used to ascertain the occurrence of the grafting and characterized the changes of the cellulose fiber after modification. The results showed that the hydrophobicity of the modified paper sheet was improved significantly after the plasma-induced grafting. The water contact angle on the paper surface reached up to 130°. The morphological differences between modified and unmodified samples were also revealed by SEM observation. The resulting paper is promising as a green-based packaging material. Copyright © 2012 Elsevier Ltd. All rights reserved.

Oxygen spectral line synthesis: 3D non-LTE with CO5BOLD hydrodynamical model atmospheres.

NASA Astrophysics Data System (ADS)

Prakapavičius, D.; Steffen, M.; Kučinskas, A.; Ludwig, H.-G.; Freytag, B.; Caffau, E.; Cayrel, R.

In this work we present first results of our current project aimed at combining the 3D hydrodynamical stellar atmosphere approach with non-LTE (NLTE) spectral line synthesis for a number of key chemical species. We carried out a full 3D-NLTE spectrum synthesis of the oxygen IR 777 nm triplet, using a modified and improved version of our NLTE3D package to calculate departure coefficients for the atomic levels of oxygen in a CO5BOLD 3D hydrodynamical solar model atmosphere. Spectral line synthesis was subsequently performed with the Linfor3D code. In agreement with previous studies, we find that the lines of the oxygen triplet produce deeper cores under NLTE conditions, due to the diminished line source function in the line forming region. This means that the solar oxygen IR 777 nm lines should be stronger in NLTE, leading to negative 3D NLTE-LTE abundance corrections. Qualitatively this result would support previous claims for a relatively low solar oxygen abundance. Finally, we outline several further steps that need to be taken in order to improve the physical realism and numerical accuracy of our current 3D-NLTE calculations.

Effects of hexanal, trans-2-hexenal, and storage temperature on shelf life of fresh sliced apples.

PubMed

Corbo, M R; Lanciotti, R; Gardini, F; Sinigaglia, M; Guerzoni, M E

2000-06-01

In this paper, the effects of hexanal and trans-2-hexenal, which are both natural molecules characterizing apple aroma, on the microbial population and on color retention of fresh sliced apples were evaluated. In particular, a central composite design (CCD) was developed to assess the individual and interactive effects of the chosen volatile molecules and storage temperatures on (i) the growth of the naturally occurring microflora, (ii) the evolution over time of an inoculated spoilage yeast (Pichia subpelliculosa), and (iii) the enzymatic browning reaction in minimally processed apples. The inclusion of hexanal and trans-2-hexenal in the storage atmosphere of apple slices determined a significant extension of shelf life also when P. subpelliculosa was inoculated at levels of 10(3) colony-forming units/g and abusive storage temperatures were used. In fact, the presence of these molecules in the packaging atmospheres considerably prolonged the lag phases of the inoculated yeast and reduced the growth potential of naturally occurring bacteria. Moreover, the addition to the modified atmosphere of low levels of the hexanal increased the color stability of the products up to 16 days.

Modelling the interactions between Pseudomonas putida and Escherichia coli O157:H7 in fish-burgers: use of the lag-exponential model and of a combined interaction index.

PubMed

Speranza, B; Bevilacqua, A; Mastromatteo, M; Sinigaglia, M; Corbo, M R

2010-08-01

The objective of the current study was to examine the interactions between Pseudomonas putida and Escherichia coli O157:H7 in coculture studies on fish-burgers packed in air and under different modified atmospheres (30 : 40 : 30 O(2) : CO(2) : N(2), 5 : 95 O(2) : CO(2) and 50 : 50 O(2) : CO(2)), throughout the storage at 8 degrees C. The lag-exponential model was applied to describe the microbial growth. To give a quantitative measure of the occurring microbial interactions, two simple parameters were developed: the combined interaction index (CII) and the partial interaction index (PII). Under air, the interaction was significant (P < 0.05) only within the exponential growth phase (CII, 1.72), whereas under the modified atmospheres, the interactions were highly significant (P < 0.001) and occurred both in the exponential and in the stationary phase (CII ranged from 0.33 to 1.18). PII values for E. coli O157:H7 were lower than those calculated for Ps. putida. The interactions occurring into the system affected both E. coli O157:H7 and pseudomonads subpopulations. The packaging atmosphere resulted in a key element. The article provides some useful information on the interactions occurring between E. coli O157:H7 and Ps. putida on fish-burgers. The proposed index describes successfully the competitive growth of both micro-organisms, giving also a quantitative measure of a qualitative phenomenon.

Detecting small holes in packages

DOEpatents

Kronberg, J.W.; Cadieux, J.R.

1996-03-19

A package containing a tracer gas, and a method for determining the presence of a hole in the package by sensing the presence of the gas outside the package are disclosed. The preferred tracer gas, especially for food packaging, is sulfur hexafluoride. A quantity of the gas is added to the package and the package is closed. The concentration of the gas in the atmosphere outside the package is measured and compared to a predetermined value of the concentration of the gas in the absence of the package. A measured concentration greater than the predetermined value indicates the presence of a hole in the package. Measuring may be done in a chamber having a lower pressure than that in the package. 3 figs.

Effect of type and content of modified montmorillonite on the structure and properties of bio-nanocomposite films based on soy protein isolate and montmorillonite

USDA-ARS?s Scientific Manuscript database

The non-biodegradable and non-renewable nature of plastic packaging has led to a renewed interest in packaging materials based on bio-nanocomposites (biopolymer matrix reinforced with nanoparticles such as layered silicates). Bio-nanocomposite films based on soy protein isolate (SPI) and modified mo...

The influence of headspace and dissolved oxygen level on growth and haemolytic BL enterotoxin production of a psychrotolerant Bacillus weihenstephanensis isolate on potato based ready-to-eat food products.

PubMed

Samapundo, S; Everaert, H; Wandutu, J N; Rajkovic, A; Uyttendaele, M; Devlieghere, F

2011-04-01

The major objective of this study was to determine the influence of the initial headspace and dissolved O(2) level and vacuum packaging on growth and diarrhoeal enterotoxin production by Bacillus weihenstephanensis on potato based ready-to-eat food products. In general, the lower the initial headspace or dissolved O(2) level the slower the maximum growth rate (μ(max), log(10) CFU g(-1) d(-1)), the longer the lag phase duration (λ, d) and the smaller the maximum population density (N(max), log(10) CFU g(-1)) became. The slowest μ(max), the longest λ and the smallest N(max) were generally found for growth under vacuum packaging. This implies shorter shelf-lives will occur at higher initial headspace or dissolved O(2) levels as the growth of B. weihenstephanensis to the infective dose of 10(5) CFU g(-1) in such atmospheres takes a shorter time. Significant consumption of dissolved O(2) only occurred when growth shifted from the lag to the exponential phase and growth generally transitioned from the exponential to the stationary phase when the dissolved O(2) levels fell below ca. 75 ppb. Diarrhoeal enterotoxin production (determined via detection of the L2 component of haemolytic BL) was similar for growth under initial headspace O(2) levels of 1-20.9%, and was only reduced when growth took place under vacuum packaging. The reduction in L2 production when growth took place under vacuum was most probably related to the low final cell densities observed under this condition. Both growth and L2 production were inhibited over a 32-day incubation period at 7 °C by 40% CO(2) irrespective of the headspace or dissolved O(2) levels. The results illustrate the importance of residual O(2) and CO(2) on the shelf-stability and safety of modified atmosphere packaged potato based ready-to-eat food products with regards to B. weihenstephanensis. Copyright © 2010 Elsevier Ltd. All rights reserved.

Growth of Listeria monocytogenes and Yersinia enterocolitica colonies under modified atmospheres at 4 and 8 degrees C using a model food system.

PubMed

Harrison, W A; Peters, A C; Fielding, L M

2000-01-01

The growth of Listeria monocytogenes and Yersinia enterocolitica colonies was studied on solid media at 4 and 8 degrees C under modified atmospheres (MAs) of 5% O2: 10% CO2: 85% N2 (MA1), 30% CO2: 70% N2 (MA2) and air (control). Colony radius, determined using computer image analysis, allowed specific growth rates (mu) and the time taken to detect bacterial colonies to be estimated, after colonies became visible. At 4 degrees C both MAs decreased the growth rates of L. monocytogenes by 1.5- and 3.0-fold under MA1 (mu = 0.02 h(-1)) and MA2 (mu = 0.01 h(-1)), respectively, as compared with the control (mu = 0.03 h(-1)). The time to detection of bacterial colonies was increased from 15 d (control) to 24 (MA1) and 29 d (MA2). At 8 degrees C MA2 decreased the growth rate by 1.5-fold (mu = 0.04 h(-1)) as compared with the control (mu = 0.06 h(-1)) and detection of colonies increased from 7 (control) to 9 d (MA2). At 4 degrees C both MAs decreased the growth rates of Y. enterocolitica by 1.5- and 2.5-fold under MA1 (mu = 0.03 h(-1)) and MA2 (mu = 0.02 h(-1)), respectively, as compared with the control (mu = 0.05 h(-1)). At 8 degrees C identical growth rates were obtained under MA1 and the control (mu = 0.07 h(-1)) whilst a decrease in the growth rate was obtained under MA2 (mu = 0.04 h(-1)). The detection of colonies varied from 6 (8 degrees C, aerobic) to 19 d (4 degrees C, MA2). Refrigerated modified atmosphere packaged foods should be maintained at 4 degrees C and below to ensure product safety.

Changes in physiological and some nutritional, nutraceuticals, chemical-physical, microbiological and sensory quality of minimally processed cactus pears cvs 'Bianca', 'Gialla' and 'Rossa' stored under passive modified atmosphere.

PubMed

Palma, Amedeo; Continella, Alberto; La Malfa, Stefano; D'Aquino, Salvatore

2018-03-01

The objective of this study was to compare the overall quality changes of minimally processed cactus pears cvs 'Bianca', Gialla' and 'Rossa' stored at 4 °C for 10 days. Periodically in-package CO 2 , O 2 and C 2 H 4 were determined and fruit were assessed for overall quality changes (pH, acidity, sugars, phenolics, betacyanins and betaxanthines, antioxidant capacity, colour, firmness, microbiological population and sensory attributes). In a preliminary study three different polymeric films were tested to select the most suitable to design a package with a short lag time to achieve steady-state conditions. Results showed marked differences between measured in-package CO 2 and O 2 values and those calculated based on respiration of peeled fruit and film permeance to CO 2 and O 2 provided by manufactures. The sensory evaluation of packed fruit indicated in film BBT-Bolphane, which created a steady-state in-package partial pressure for CO 2 of 4.3-4.8 kPa and for O 2 of 4.8-5.5 kPa, as the best film. Results of in-package gas composition with the three cultivars were similar to those achieved in cv. 'Gialla' with the preliminary test. All measured qualitative parameters changed slightly over the storage period for all cultivars and followed the same trend, despite significant differences existing among cultivars. This study clearly showed a similar physiological behavior of minimally processed 'Bianca', 'Gialla' and 'Rossa' cactus pears. Storage conditions optimal for one cultivar fit well for the others; thus mixing fruit of different cultivars in a package designed for one specific cultivar does not lead to relevant deviation from expected results. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Improved shelf life of dried Beauveria bassiana blastospores using convective drying and active packaging processes.

PubMed

Mascarin, Gabriel Moura; Jackson, Mark A; Behle, Robert W; Kobori, Nilce N; Júnior, Ítalo Delalibera

2016-10-01

The yeast form (blastospore) of the dimorphic insect-pathogenic fungus Beauveria bassiana can be rapidly produced using liquid fermentation methods but is generally unable to survive rapid dehydration processes or storage under non-refrigerated conditions. In this study, we evaluated the influence of two convective drying methods, various modified atmosphere packaging systems, and storage temperatures on the desiccation tolerance, storage stability, and virulence of blastospores of B. bassiana ESALQ 1432. All blastospore formulations were dried to <5 % water content equivalent to aw < 0.3. The viability of B. bassiana blastospores after air drying and spray drying was greater than 80 %. Vacuum-packaged blastospores remained viable longer when stored at 4 °C compared with 28 °C with virtually no loss in viability over 9 months regardless the drying method. When both oxygen and moisture scavengers were added to sealed packages of dried blastospore formulations stored at 28 °C, viability was significantly prolonged for both air- and spray-dried blastospores. The addition of ascorbic acid during spray drying did not improve desiccation tolerance but enhanced cell stability (∼twofold higher half-life) when stored at 28 °C. After storage for 4 months at 28 °C, air-dried blastospores produced a lower LC80 and resulted in higher mortality to whitefly nymphs (Bemisia tabaci) when compared with spray-dried blastospores. These studies identified key storage conditions (low aw and oxygen availability) that improved blastospore storage stability at 28 °C and will facilitate the commercial development of blastospores-based bioinsecticides.

Meat Processing Plant Microbiome and Contamination Patterns of Cold-Tolerant Bacteria Causing Food Safety and Spoilage Risks in the Manufacture of Vacuum-Packaged Cooked Sausages

PubMed Central

Rahkila, Riitta; Ali, Javeria; Rousu, Juho; Björkroth, K. Johanna

2015-01-01

Refrigerated food processing facilities are specific man-made niches likely to harbor cold-tolerant bacteria. To characterize this type of microbiota and study the link between processing plant and product microbiomes, we followed and compared microbiota associated with the raw materials and processing stages of a vacuum-packaged, cooked sausage product affected by a prolonged quality fluctuation with occasional spoilage manifestations during shelf life. A total of 195 samples were subjected to culturing and amplicon sequence analyses. Abundant mesophilic psychrotrophs were detected within the microbiomes throughout the different compartments of the production plant environment. However, each of the main genera of food safety and quality interest, e.g., Leuconostoc, Brochothrix, and Yersinia, had their own characteristic patterns of contamination. Bacteria from the genus Leuconostoc, commonly causing spoilage of cold-stored, modified-atmosphere-packaged foods, were detected in high abundance (up to >98%) in the sausages studied. The same operational taxonomic units (OTUs) were, however, detected in lower abundances in raw meat and emulsion (average relative abundance of 2% ± 5%), as well as on the processing plant surfaces (<4%). A completely different abundance profile was found for OTUs phylogenetically close to the species Yersinia pseudotuberculosis. These OTUs were detected in high abundance (up to 28%) on the processing plant surfaces but to a lesser extent (<1%) in raw meat, sausage emulsion, and sausages. The fact that Yersinia-like OTUs were found on the surfaces of a high-hygiene packaging compartment raises food safety concerns related to their resilient existence on surfaces. PMID:26231646

Influence of good manufacturing practices on the shelf life of refrigerated fillets of tilapia (Oreochromis niloticus) packed in modified atmosphere and gamma-irradiated

PubMed Central

Monteiro, Maria Lúcia Guerra; Mársico, Eliane Teixeira; Mano, Sérgio Borges; Teixeira, Claudia Emília; da Cruz Silva Canto, Anna Carolina Vilhena; de Carvalho Vital, Helio; Conte-Júnior, Carlos Adam

2013-01-01

This study evaluated the influence of good manufacturing practices (GMP) on the shelf life of refrigerated fillets of Nile tilapia (Oreochromis niloticus) packed in modified atmosphere packaging (MAP) and irradiated. In a first series of experiments, 120 tilapia fillets kept under controlled sanitary conditions were purchased from a fish market managed by a cooperative. A second lot totaling 200 tilapia fillets was obtained under controlled storage conditions from a pilot plant. The combined effects of MAP (40% CO2 and 60% N2) and irradiation (1.5 kGy) were investigated by monitoring physical and chemical (total volatile bases and pH), bacteriological (aerobic heterotrophic mesophilic and psychrophilic bacteria) and sensory (acceptance test) changes in the samples. The quality of samples decreased with storage time regardless of the treatment, remaining higher in fillets produced in the pilot plant in comparison with the commercially produced fillets. The observed shelf life of nonirradiated commercially produced fillets was only 3 days, compared to 8 days for those produced in the pilot plant, probably due to GMP in the latter. It was concluded that, even with a combination of proven conservation methods for meats, the adoption of good manufacturing practices still remains essential before, during, and after the filleting process in order to ensure the effectiveness of the entire treatment. PMID:24804034

Effect of modified atmosphere packaging and temperature abuse on flavor related volatile compounds of rocket leaves (Diplotaxis tenuifolia L.).

PubMed

Mastrandrea, Leonarda; Amodio, Maria Luisa; Pati, Sandra; Colelli, Giancarlo

2017-07-01

The effect of storage conditions on flavor-related volatile composition of wild rocket ( Diplotaxis tenuifolia ) was investigated on Modified Atmosphere packed (MAP) leaves stored under isothermal and non-isothermal conditions. In a first experiment the effect of MAP was compared to the storage in air at 5 °C; a second experiment aimed to study the effect of non isothermal conditions, with two temperature abuses (at 13 °C for 24 h) during a 5 °C. Twenty-four volatiles were detected, including C6, C5, isothiocyanate, lipid-derived and sulfur compounds. In the first experiment, MAP-stored rocket showed a slower loss of typical flavour volatiles (thiocyanates and isothiocyanates) and a slower production of off-flavors until 6 days of storage, compared to leaves stored in air. After this time, dimethyl sulfide and acetaldehyde dramatically increased in MAP-stored rocket samples. In the second experiment, samples stored under non-isothermal conditions showed lower O 2 and higher CO 2 concentrations than samples stored under isothermal conditions. Rocket leaves stored under non-isothermal conditions showed an increased production of volatiles responsible of off-flavors (acetaldehyde and dimethyl sulfide) following temperature abuse comparing to storage in isothermal condition. Thus, dimethyl sulfide and acetaldehyde could be effective markers for tracking the effect of temperature fluctuations on rocket during storage.

Control of Escherichia coli and Listeria monocytogenes in suckling-lamb meat evaluated using microbial challenge tests.

PubMed

Osés, S M; Diez, A M; Gómez, E M; Wilches-Pérez, D; Luning, P A; Jaime, I; Rovira, J

2015-12-01

Escherichia coli and Listeria monocytogenes microbial challenge tests were performed on fresh suckling-lamb meat. Hind leg slices were chilly stored under two modified atmosphere packaging (MAP) environments (A: 15%O2/60%CO2/25%N2, B: 15%O2/30%CO2/55%N2) and vacuum packaging (V). Only E. coli was reduced between 0.72-1.25 log cfu/g from day 1 to day 4 by the combined use of MAP/V, chilling storage and the growth of native lactic acid bacteria. However, L. monocytogenes was not inhibited by the application of V or MAP. Even do, in inoculated samples, this pathogen increased between 1.2-2.7 log cfu/g throughout the study. Consequently, a second experiment that combined the effects of MAP/V and a protective culture (Leuconostoc pseudomesenteroides PCK 18) against L. monocytogenes was designed. Two different levels of protective cultures were assayed (4 and 6 log cfu/g). Lc. pseudomesenteroides PCK 18 was able to control the growth of L. monocytogenes when the differences between them are higher than 2 log cfu/g. Moreover, when high level of protective culture was used a significant reduction of L. monocytogenes counts were noticed in samples packaged in 60% of CO2 along the storage period, although sensory properties were also affected. Copyright © 2015 Elsevier Ltd. All rights reserved.

Combined effect of MAP and active compounds on fresh blue fish burger.

PubMed

Del Nobile, M A; Corbo, M R; Speranza, B; Sinigaglia, M; Conte, A; Caroprese, M

2009-11-15

The combined effects of three essential oils [thymol, lemon extract and grapefruit seed extract (GFSE)] and modified atmosphere packaging conditions (MAP) on quality retention of blue fish burgers was studied and discussed. In particular, samples were packaged in air and in three different gas mix compositions: 30:40:30 O(2):CO(2):N(2), 50:50 O(2):CO(2) and 5:95 O(2):CO(2). During a 28-day storage period at 4 degrees C, the nutritional, microbiological and sensorial quality of the packed products was assessed. The potential development of biogenic amines was also evaluated. The obtained results highlight the possibility to improve the microbial quality of blue fish burgers by using very small amount of thymol (110ppm), GFSE (100ppm) and lemon extract (120ppm) in combination with MAP. Based primarily on microbiological results, the combined use of the tested natural preservatives and a packaging system characterized by a high CO(2)-concentration, was able to guarantee the microbial acceptability of fish burgers until the 28th day of storage at 4 degrees C. On the other hand, results from sensory analyses showed that sensorial quality was the sub-index that limited the burgers shelf life (to about 22-23days), even if the proposed strategy was also effective in minimizing the sensory quality loss of the product having no effect on its nutritional quality.

Effect of pretreatment with carbon monoxide and ozone on the quality of vacuum packaged beef meats.

PubMed

Lyu, Fei; Shen, Kejing; Ding, Yuting; Ma, Xin

2016-07-01

Beef meats without pretreatment (CK) or pretreated with different volume ratios of carbon monoxide and ozone of 100%CO (T1), 2%O3+98%CO (T2), 5%O3+95%CO (T3) and 10%O3+90%CO (T4) using modified atmosphere packages for 1.5h, after that they were vacuum-packaged and stored in 0°C refrigerator for 46days. The surface color a* values and sensory scores of T1, T2, T3 and T4 were significant higher than CK (p<0.05) during storage. In the mid and later storage, the drip loss, total viable counts (TVC), metmyoglobin (met-Mb), thiobarbituric acid reactive substances (TBARS), total volatile basic nitrogen (TVB-N) and pH of T1, T2, T3 and T4 were significantly lower than CK (p<0.05), and these values of T2, T3 and T4 were significantly lower than T1 in the later storage. In conclusion, O3 in the combination didn't affect the color-developing effect of CO, and could help CO maintain the meat quality. Therefore, the pretreatment of CO combined with O3 at certain concentrations can be a promising technique to maintain the quality of beef meats. Copyright © 2016 Elsevier Ltd. All rights reserved.

Program Package for the Analysis of High Resolution High Signal-To-Noise Stellar Spectra

NASA Astrophysics Data System (ADS)

Piskunov, N.; Ryabchikova, T.; Pakhomov, Yu.; Sitnova, T.; Alekseeva, S.; Mashonkina, L.; Nordlander, T.

2017-06-01

The program package SME (Spectroscopy Made Easy), designed to perform an analysis of stellar spectra using spectral fitting techniques, was updated due to adding new functions (isotopic and hyperfine splittins) in VALD and including grids of NLTE calculations for energy levels of few chemical elements. SME allows to derive automatically stellar atmospheric parameters: effective temperature, surface gravity, chemical abundances, radial and rotational velocities, turbulent velocities, taking into account all the effects defining spectral line formation. SME package uses the best grids of stellar atmospheres that allows us to perform spectral analysis with the similar accuracy in wide range of stellar parameters and metallicities - from dwarfs to giants of BAFGK spectral classes.

Morphological and antibacterial properties of modified paper by PS nanocomposites for packaging applications.

PubMed

Youssef, Ahmed M; Kamel, S; El-Samahy, M A

2013-10-15

With the increasing sustainability trend with packaging materials, paper and polymer nanocomposites represent a novel class of packaging materials. This study evaluates the potential achievement of alternative sustainable materials as antibacterial packaging application. Paper sheet from rice straw coated with 5 or 10% polystyrene (PS) nanocomposites using titanium dioxide nanoparticles (TiO2-NPs) doped or undoped with sliver nanoparticles (Ag-NPs) were prepared. The morphology of the uncoated and coated paper sheets was studied by SEM. The treated paper sheets were analyzed for their elemental composition using EDAX. The Barrier, air permeability, cob test, as well as mechanical properties and tensile strength were also evaluated. The inhibitory effect of modified paper sheets against Pseudomonas, Staphylococcus aureus, Candida, and Staphylococcus were investigated. Copyright © 2013 Elsevier Ltd. All rights reserved.

User's manual for the coupled rotor/airframe vibration analysis graphic package

NASA Technical Reports Server (NTRS)

Studwell, R. E.

1982-01-01

User instructions for a graphics package for coupled rotor/airframe vibration analysis are presented. Responses to plot package messages which the user must make to activate plot package operations and options are described. Installation instructions required to set up the program on the CDC system are included. The plot package overlay structure and subroutines which have to be modified for the CDC system are also described. Operating instructions for CDC applications are included.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stevens, K; Huang, T; Buttler, D

We present the C-Cat Wordnet package, an open source library for using and modifying Wordnet. The package includes four key features: an API for modifying Synsets; implementations of standard similarity metrics, implementations of well known Word Sense Disambiguation algorithms, and an implementation of the Castanet algorithm. The library is easily extendible and usable in many runtime environments. We demonstrate it's use on two standard Word Sense Disambiguation tasks and apply the Castanet algorithm to a corpus.

Radiative transfer through terrestrial atmosphere and ocean: Software package SCIATRAN

NASA Astrophysics Data System (ADS)

Rozanov, V. V.; Rozanov, A. V.; Kokhanovsky, A. A.; Burrows, J. P.

2014-01-01

SCIATRAN is a comprehensive software package for the modeling of radiative transfer processes in the terrestrial atmosphere and ocean in the spectral range from the ultraviolet to the thermal infrared (0.18 - 40 μm) including multiple scattering processes, polarization, thermal emission and ocean-atmosphere coupling. The software is capable of modeling spectral and angular distributions of the intensity or the Stokes vector of the transmitted, scattered, reflected, and emitted radiation assuming either a plane-parallel or a spherical atmosphere. Simulations are done either in the scalar or in the vector mode (i.e. accounting for the polarization) for observations by space-, air-, ship- and balloon-borne, ground-based, and underwater instruments in various viewing geometries (nadir, off-nadir, limb, occultation, zenith-sky, off-axis). All significant radiative transfer processes are accounted for. These are, e.g. the Rayleigh scattering, scattering by aerosol and cloud particles, absorption by gaseous components, and bidirectional reflection by an underlying surface including Fresnel reflection from a flat or roughened ocean surface. The software package contains several radiative transfer solvers including finite difference and discrete-ordinate techniques, an extensive database, and a specific module for solving inverse problems. In contrast to many other radiative transfer codes, SCIATRAN incorporates an efficient approach to calculate the so-called Jacobians, i.e. derivatives of the intensity with respect to various atmospheric and surface parameters. In this paper we discuss numerical methods used in SCIATRAN to solve the scalar and vector radiative transfer equation, describe databases of atmospheric, oceanic, and surface parameters incorporated in SCIATRAN, and demonstrate how to solve some selected radiative transfer problems using the SCIATRAN package. During the last decades, a lot of studies have been published demonstrating that SCIATRAN is a valuable tool for a wide range of remote sensing applications. Here, we present some selected comparisons of SCIATRAN simulations to published benchmark results, independent radiative transfer models, and various measurements from satellite, ground-based, and ship instruments. Methods for solving inverse problems related to remote sensing of the Earth's atmosphere using the SCIATRAN software are outside the scope of this study and will be discussed in a follow-up paper. The SCIATRAN software package along with a detailed User's Guide is freely available for non-commercial use via the webpage of the Institute of Environmental Physics (IUP), University of Bremen: http://www.iup.physik.uni-bremen.de/sciatran.

Shelf life of ready to use peeled shrimps as affected by thymol essential oil and modified atmosphere packaging.

PubMed

Mastromatteo, Marianna; Danza, Alessandra; Conte, Amalia; Muratore, Giuseppe; Del Nobile, Matteo Alessandro

2010-12-15

In this work the influence of different packaging strategies on the shelf life of ready to use peeled shrimps was investigated. First, the effectiveness of the coating (Coat) and the active coating loaded with different concentrations of thymol (Coat-500, Coat-1000, and Coat-1500) on the quality loss of the investigated food product packaged in air was addressed; afterwards, the thymol concentration that had shown the best performance was used in combination with MAP (5% O(2); 95% CO(2)). Microbial cell load of main spoilage microorganisms, pH and sensorial quality were monitored during the refrigerated storage. Results of the first step suggested that the sole coating did not affect the microbial growth. A slight antimicrobial effect was obtained when the coating was loaded with thymol and a concentration dependence was also observed. Moreover, the active coating was effective in minimizing the sensory quality loss of the investigated product, it was particularly true at the lowest thymol concentration. In the second step, the thymol concentration (1000 ppm) that showed the strike balance between microbial and sensorial quality was chosen in combination with MAP. As expected, MAP significantly affected the growth of the mesophilic bacteria. In particular, a cell load reduction of about 2 log cycle for the samples under MAP respect to that in air was obtained. Moreover, the MAP packaging inhibited the growth of the Pseudomonas spp. and hydrogen sulphide-producing bacteria. The MAP alone was not able to improve the shelf life of the uncoated samples. In fact, no significant difference between the control samples packaged in air and MAP was observed. Whilst, the use of coating under MAP condition prolonged the shelf life of about 6 days with respect to the same samples packaged in air. Moreover, when the MAP was used in combination with thymol, a further shelf life prolongation with respect to the samples packaged in air was observed. In particular, a shelf life of about 14 days for the active coating under MAP compared to the same samples in air (5 days) was obtained. Copyright © 2010 Elsevier B.V. All rights reserved.

A fast hidden line algorithm with contour option. M.S. Thesis

NASA Technical Reports Server (NTRS)

Thue, R. E.

1984-01-01

The JonesD algorithm was modified to allow the processing of N-sided elements and implemented in conjunction with a 3-D contour generation algorithm. The total hidden line and contour subsystem is implemented in the MOVIE.BYU Display package, and is compared to the subsystems already existing in the MOVIE.BYU package. The comparison reveals that the modified JonesD hidden line and contour subsystem yields substantial processing time savings, when processing moderate sized models comprised of 1000 elements or less. There are, however, some limitations to the modified JonesD subsystem.

Diagnostic Testing Package DX v 2.0 Technical Specification. Methodology Project.

ERIC Educational Resources Information Center

McArthur, David

This paper contains the technical specifications, schematic diagrams, and program printout for a computer software package for the development and administration of diagnostic tests. The second version of the Diagnostic Testing Package DX consists of a PASCAL-based set of modules located in two main programs: (1) EDITTEST creates, modifies, and…

IIP Update: A Packaged Coherent Doppler Wind Lidar Transceiver. Doppler Aerosol WiNd Lidar (DAWN)

NASA Technical Reports Server (NTRS)

Kavaya, Michael J.; Koch, Grady J.; Yu, Jirong; Trieu, Bo C.; Amzajerdian, Farzin; Singh, Upendra N.; Petros, Mulugeta

2006-01-01

The state-of-the-art 2-micron coherent Doppler wind lidar breadboard at NASA/LaRC will be engineered and compactly packaged consistent with future aircraft flights. The packaged transceiver will be integrated into a coherent Doppler wind lidar system test bed at LaRC. Atmospheric wind measurements will be made to validate the packaged technology. This will greatly advance the coherent part of the hybrid Doppler wind lidar solution to the need for global tropospheric wind measurements.

Modelling the influence of time and temperature on the respiration rate of fresh oyster mushrooms.

PubMed

Azevedo, Sílvia; Cunha, Luís M; Fonseca, Susana C

2015-12-01

The respiration rate of mushrooms is an important indicator of postharvest senescence. Storage temperature plays a major role in their rate of respiration and, therefore, in their postharvest life. In this context, reliable predictions of respiration rates are critical for the development of modified atmosphere packaging that ultimately will maximise the quality of the product to be presented to consumers. This work was undertaken to study the influence of storage time and temperature on the respiration rate of oyster mushrooms. For that purpose, oyster mushrooms were stored at constant temperatures of 2, 6, 10, 14 and 18 ℃ under ambient atmosphere. Respiration rate data were measured with 8-h intervals up to 240 h. A decrease of respiration rate was found after cutting of the carpophores. Therefore, time effect on respiration rate was modelled using a first-order decay model. The results also show the positive influence of temperature on mushroom respiration rate. The model explaining the effect of time on oyster mushroom's respiration rate included the temperature dependence according to the Arrhenius equation, and the inclusion of a parameter describing the decrease of the respiration rate, from the initial time until equilibrium. These yielded an overall model that fitted well to the experimental data. Moreover, results show that the overall model is useful to predict respiration rate of oyster mushrooms at different temperatures and times, using the initial respiration rate of mushrooms. Furthermore, predictive modelling can be relevant for the choice of an appropriate packaging system for fresh oyster mushrooms. © The Author(s) 2014.

Effects of packaging systems and fat concentrations on microbiology, sensory and physical properties of ground beef stored at 4±1°C for 25 days.

PubMed

Lavieri, N; Williams, S K

2014-08-01

This study evaluated effects of modified atmosphere (MAP, 0.4% carbon monoxide [CO], 30% carbon dioxide, and 69.6% nitrogen), vacuum (VP) and polyvinyl chloride (PVC) packaging systems and fat levels (10, 20 and 30% fat) on ground beef stored at 4 ± 1°C for 25 days for microbiology, sensory, pH, thiobarbituric acid reactive substances (TBARS), objective color, headspace and residual CO. As storage time increased, pH decreased (P< 0.05) for MAP and VP and increased (P < 0.05) for PVC. TBARS varied (P < 0.05) among MAP and VP treatments. Except for day 1, CO headspace concentrations were similar among fat concentrations, and residual CO absorption in meat increased (P < 0.05) for all MAP treatments. In all treatments, degree of lightness was similar, redness decreased and brown discoloration increased during storage. As psychrotrophic bacteria counts increased, panelists detected color and off-odor deterioration in all systems. The CO treatment had no effect on maintaining the carboxymyoglobin "cherry red" fresh meat color during meat spoilage. Published by Elsevier Ltd.

The effect of high pressure and residual oxygen on the color stability of minced cured restructured ham at different levels of drying, pH, and NaCl.

PubMed

Bak, Kathrine Holmgaard; Lindahl, Gunilla; Karlsson, Anders H; Lloret, Elsa; Gou, Pere; Arnau, Jacint; Orlien, Vibeke

2013-10-01

Color stability of minced cured restructured ham was studied by considering the effects of high pressure (HP) (600 MPa, 13°C, 5 min), raw meat pH24 (low, normal, high), salt content (15, 30 g/kg), drying (20%, 50% weight loss), and residual oxygen level (0.02%-0.30%). Raw hams were selected by pH24 in Semimembranosus, mixed with additives, frozen, sliced, and dried by the Quick-Dry-Slice® (QDS) process followed by HP treatment or not (control). Packaging and storage simulated industrial packaging: modified atmosphere containing 80% N2, 20% CO2, and residual O2 in one of three intervals: <0.1%, 0.1%-0.2%, or 0.2%-0.3%, and retail storage conditions: chill storage, 12 h light, 12 h darkness. HP improved the stability of the redness of 20% QDS hams, while the stabilizing effect on 50% QDS hams was smaller, concluding that water has the dominating role. Raw meat pH24, salt content, and residual oxygen level had varying effects on the stability of the red color. Copyright © 2013 Elsevier Ltd. All rights reserved.

Synoptic Traveling Weather Systems on Mars: Effects of Radiatively-Active Water Ice Clouds

NASA Astrophysics Data System (ADS)

Hollingsworth, Jeffery L.; Kahre, Melinda A.; Haberle, Robert; Atsuki Urata, Richard

2016-10-01

Atmospheric aerosols on Mars are critical in determining the nature of its thermal structure, its large-scale circulation, and hence the overall climate of the planet. We conduct multi-annual simulations with the latest version of the NASA Ames Mars global climate model (GCM), gcm2.3+, that includes a modernized radiative-transfer package and complex water-ice cloud microphysics package which permit radiative effects and interactions of suspended atmospheric aerosols (e.g., water ice clouds, water vapor, dust, and mutual interactions) to influence the net diabatic heating. Results indicate that radiatively active water ice clouds profoundly affect the seasonal and annual mean climate. The mean thermal structure and balanced circulation patterns are strongly modified near the surface and aloft. Warming of the subtropical atmosphere at altitude and cooling of the high latitude atmosphere at low levels takes place, which increases the mean pole-to-equator temperature contrast (i.e., "baroclinicity"). With radiatively active water ice clouds (RAC) compared to radiatively inert water ice clouds (nonRAC), significant changes in the intensity of the mean state and forced stationary Rossby modes occur, both of which affect the vigor and intensity of traveling, synoptic period weather systems. Such weather systems not only act as key agents in the transport of heat and momentum beyond the extent of the Hadley circulation, but also the transport of trace species such as water vapor, water ice-clouds, dust and others. The northern hemisphere (NH) forced Rossby waves and resultant wave train are augmented in the RAC case: the modes are more intense and the wave train is shifted equatorward. Significant changes also occur within the subtropics and tropics. The Rossby wave train sets up, combined with the traveling synoptic-period weather systems (i.e., cyclones and anticyclones), the geographic extent of storm zones (or storm tracks) within the NH. A variety of circulation features will be presented which indicate contrasts between the RAC and nonRAC cases, and which highlight key effects radiatively-active clouds have on physical and dynamical processes active in the current climate of Mars.

A stratospheric balloon experiment to test the Huygens atmospheric structure instrument (HASI)

NASA Astrophysics Data System (ADS)

Fulchignoni, M.; Aboudan, A.; Angrilli, F.; Antonello, M.; Bastianello, S.; Bettanini, C.; Bianchini, G.; Colombatti, G.; Ferri, F.; Flamini, E.; Gaborit, V.; Ghafoor, N.; Hathi, B.; Harri, A.-M.; Lehto, A.; Lion Stoppato, P. F.; Patel, M. R.; Zarnecki, J. C.

2004-08-01

We developed a series of balloon experiments parachuting a 1:1 scale mock-up of the Huygens probe from an altitude just over 30 km to simulate at planetary scale the final part of the descent of the probe through Titan's lower atmosphere. The terrestrial atmosphere represents a natural laboratory where most of the physical parameters meet quite well the bulk condition of Titan's environment, in terms of atmosphere composition, pressure and mean density ranges, though the temperature range will be far higher. The probe mock-up consists of spares of the HASI sensor packages, housekeeping sensors and other dedicated sensors, and also incorporates the Huygens Surface Science Package (SSP) Tilt sensor and a modified version of the Beagle 2 UV sensor, for a total of 77 acquired sensor channels, sampled during ascent, drift and descent phase. An integrated data acquisition and instrument control system, simulating the HASI data-processing unit (DPU), has been developed, based on PC architecture and soft-real-time application. Sensor channels were sampled at the nominal HASI data rates, with a maximum rate of 1 kHz. Software has been developed for data acquisition, onboard storage and telemetry transmission satisfying all requests for real-time monitoring, diagnostic and redundancy. The mock-up of the Huygens probe mission was successfully launched for the second time (first launch in summer 2001, see Gaborit et al., 2001) with a stratospheric balloon from the Italian Space Agency Base "Luigi Broglio" in Sicily on May 30, 2002, and recovered with all sensors still operational. The probe was lifted to an altitude of 32 km and released to perform a parachuted descent lasting 53 min, to simulate the Huygens mission at Titan. Preliminary aerodynamic study of the probe has focused upon the achievement of a descent velocity profile reproducing the expected profile of Huygens probe descent into Titan. We present here the results of this experiment discussing their relevance in the analysis of the data which will be obtained during the Huygens mission at Titan.

Synoptic Traveling Weather Systems on Mars: Effects of Radiatively-Active Water Ice Clouds

NASA Technical Reports Server (NTRS)

Hollingsworth, Jeffery; Kahre, Melinda; Haberle, Robert; Urata, Richard

2017-01-01

Atmospheric aerosols on Mars are critical in determining the nature of its thermal structure, its large-scale circulation, and hence the overall climate of the planet. We conduct multi-annual simulations with the latest version of the NASA Ames Mars global climate model (GCM), gcm2.3+, that includes a modernized radiative-transfer package and complex water-ice cloud microphysics package which permit radiative effects and interactions of suspended atmospheric aerosols (e.g., water ice clouds, water vapor, dust, and mutual interactions) to influence the net diabatic heating. Results indicate that radiatively active water ice clouds profoundly affect the seasonal and annual mean climate. The mean thermal structure and balanced circulation patterns are strongly modified near the surface and aloft. Warming of the subtropical atmosphere at altitude and cooling of the high latitude atmosphere at low levels takes place, which increases the mean pole-to-equator temperature contrast (i.e., "baroclinicity"). With radiatively active water ice clouds (RAC) compared to radiatively inert water ice clouds (nonRAC), significant changes in the intensity of the mean state and forced stationary Rossby modes occur, both of which affect the vigor and intensity of traveling, synoptic period weather systems. Such weather systems not only act as key agents in the transport of heat and momentum beyond the extent of the Hadley circulation, but also the transport of trace species such as water vapor, water ice-clouds, dust and others. The northern hemisphere (NH) forced Rossby waves and resultant wave train are augmented in the RAC case: the modes are more intense and the wave train is shifted equatorward. Significant changes also occur within the subtropics and tropics. The Rossby wave train sets up, combined with the traveling synoptic period weather systems (i.e., cyclones and anticyclones), the geographic extent of storm zones (or storm tracks) within the NH. A variety of circulation features will be presented which indicate contrasts between the RAC and nonRAC cases, and which highlight key effects radiatively-active clouds have on physical and dynamical processes active in the current climate of Mars.

Synoptic Traveling Weather Systems on Mars: Effects of Radiatively-Active Water Ice Clouds

NASA Technical Reports Server (NTRS)

Hollingsworth, Jeffery; Kahre, Melinda; Haberle, Robert; Urata, Richard

2017-01-01

Atmospheric aerosols on Mars are critical in determining the nature of its thermal structure, its large-scale circulation, and hence the overall climate of the planet. We conduct multi-annual simulations with the latest version of the NASA Ames Mars global climate model (GCM), gcm2.3+, that includes a modernized radiative-transfer package and complex water-ice cloud microphysics package which permit radiative effects and interactions of suspended atmospheric aerosols (e.g., water ice clouds, water vapor, dust, and mutual interactions) to influence the net diabatic heating. Results indicate that radiatively active water ice clouds profoundly affect the seasonal and annual mean climate. The mean thermal structure and balanced circulation patterns are strongly modified near the surface and aloft. Warming of the subtropical atmosphere at altitude and cooling of the high latitude atmosphere at low levels takes place, which increases the mean pole-to-equator temperature contrast (i.e., "baroclinicity"). With radiatively active water ice clouds (RAC) compared to radiatively inert water ice clouds (nonRAC), significant changes in the intensity of the mean state and forced stationary Rossby modes occur, both of which affect the vigor and intensity of traveling, synoptic period weather systems.Such weather systems not only act as key agents in the transport of heat and momentum beyond the extent of the Hadley circulation, but also the transport of trace species such as water vapor, water ice-clouds, dust and others. The northern hemisphere (NH) forced Rossby waves and resultant wave train are augmented in the RAC case: the modes are more intense and the wave train is shifted equatorward. Significant changes also occur within the subtropics and tropics. The Rossby wave train sets up, combined with the traveling synoptic period weather systems (i.e., cyclones and anticyclones), the geographic extent of storm zones (or storm tracks) within the NH. A variety of circulation features will be presented which indicate contrasts between the RAC and nonRAC cases, and which highlight key effects radiatively-active clouds have on physical and dynamical processes active in the current climate of Mars.

77 FR 1125 - Self-Regulatory Organizations; The NASDAQ Stock Market LLC; Notice of Filing and Immediate...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-09

... Proposed Rule Change To Modify Fees for the Trading and Compliance Data Package January 3, 2012. Pursuant... reports available to member firms via NasdaqTrader.com Trading and Compliance Data Package under NASDAQ... deletions are in brackets. 7021. NasdaqTrader.com Trading and Compliance Data Package Fee The charge to be...

Monitoring of Microbial Metabolites and Bacterial Diversity in Beef Stored under Different Packaging Conditions ▿ †

PubMed Central

Ercolini, Danilo; Ferrocino, Ilario; Nasi, Antonella; Ndagijimana, Maurice; Vernocchi, Pamela; La Storia, Antonietta; Laghi, Luca; Mauriello, Gianluigi; Guerzoni, M. Elisabetta; Villani, Francesco

2011-01-01

Beef chops were stored at 4°C under different conditions: in air (A), modified-atmosphere packaging (MAP), vacuum packaging (V), or bacteriocin-activated antimicrobial packaging (AV). After 0 to 45 days of storage, analyses were performed to determine loads of spoilage microorganisms, microbial metabolites (by solid-phase microextraction [SPME]-gas chromatography [GC]-mass spectrometry [MS] and proton nuclear magnetic resonance [1H NMR]), and microbial diversity (by PCR–denaturing gradient gel electrophoresis [DGGE] and pyrosequencing). The microbiological shelf life of meat increased with increasing selectivity of storage conditions. Culture-independent analysis by pyrosequencing of DNA extracted directly from meat showed that Brochothrix thermosphacta dominated during the early stages of storage in A and MAP, while Pseudomonas spp. took over during further storage in A. Many different bacteria, several of which are usually associated with soil rather than meat, were identified in V and AV; however, lactic acid bacteria (LAB) dominated during the late phases of storage, and Carnobacterium divergens was the most frequent microorganism in AV. Among the volatile metabolites, butanoic acid was associated with the growth of LAB under V and AV storage conditions, while acetoin was related to the other spoilage microbial groups and storage conditions. 1H NMR analysis showed that storage in air was associated with decreases in lactate, glycogen, IMP, and ADP levels and with selective increases in levels of 3-methylindole, betaine, creatine, and other amino acids. The meat microbiota is significantly affected by storage conditions, and its changes during storage determine complex shifts in the metabolites produced, with a potential impact on meat quality. PMID:21803905

Meat Processing Plant Microbiome and Contamination Patterns of Cold-Tolerant Bacteria Causing Food Safety and Spoilage Risks in the Manufacture of Vacuum-Packaged Cooked Sausages.

PubMed

Hultman, Jenni; Rahkila, Riitta; Ali, Javeria; Rousu, Juho; Björkroth, K Johanna

2015-10-01

Refrigerated food processing facilities are specific man-made niches likely to harbor cold-tolerant bacteria. To characterize this type of microbiota and study the link between processing plant and product microbiomes, we followed and compared microbiota associated with the raw materials and processing stages of a vacuum-packaged, cooked sausage product affected by a prolonged quality fluctuation with occasional spoilage manifestations during shelf life. A total of 195 samples were subjected to culturing and amplicon sequence analyses. Abundant mesophilic psychrotrophs were detected within the microbiomes throughout the different compartments of the production plant environment. However, each of the main genera of food safety and quality interest, e.g., Leuconostoc, Brochothrix, and Yersinia, had their own characteristic patterns of contamination. Bacteria from the genus Leuconostoc, commonly causing spoilage of cold-stored, modified-atmosphere-packaged foods, were detected in high abundance (up to >98%) in the sausages studied. The same operational taxonomic units (OTUs) were, however, detected in lower abundances in raw meat and emulsion (average relative abundance of 2%±5%), as well as on the processing plant surfaces (<4%). A completely different abundance profile was found for OTUs phylogenetically close to the species Yersinia pseudotuberculosis. These OTUs were detected in high abundance (up to 28%) on the processing plant surfaces but to a lesser extent (<1%) in raw meat, sausage emulsion, and sausages. The fact that Yersinia-like OTUs were found on the surfaces of a high-hygiene packaging compartment raises food safety concerns related to their resilient existence on surfaces. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The effects of packaging method (vacuum pouch vs. plastic tray) on spoilage in a cook-chill pork-based dish kept under refrigeration.

PubMed

Díaz, Pedro; Garrido, María Dolores; Bañón, Sancho

2010-03-01

The effects of two packaging methods on the spoilage of a cook-chill pork-based dish kept under refrigeration were studied. Raw pork cuts and pre-cooked tomato sauce were packed under vacuum "sous vide" in polyamide-polypropylene pouches (SV) or into translucent polypropylene trays under modified atmosphere (80% N(2)+20% CO(2)) and sealed with a top film (PT). Samples were cooked inside the pack at an oven temperature/time of 70 degrees C/7h, chilled at 3 degrees C and stored at 2 degrees C for up to 90days. Microbial (psychrotrophs, lactic-acid bacteria, Enterobacteriaceae, moulds and yeasts), physical-chemical (pH, water activity and total acidity) and sensory (colour, odour, flavour, texture and acceptance) parameters were determined. Heat penetration was faster in SV (2 degrees C/min) than in PT (1 degrees C/min) (core temperature). Both packaging methods were equally effective in protecting against microbial spoilage for 90 day at 2 degrees C. Minor counts were only detected for lactic-acid bacteria and anaerobic psychrotrophs in SV. No Enterobacteriaceae growth was found. Slight differences between SV and PT in pH and total acidity were observed. SV and PT had similar effects on the sensory preservation of the dishes. A gradual loss of acceptance of the cooked pork and tomato sauce was observed. Rancid flavour in PT and warmed-over-flavour in SV were noted in the final stages of storage. According to acceptance scores, the shelf-life of both SV and PT was 56 days at 2 degrees C. Both packaging methods can be used to manufacture sous vide meat-based dishes subsequently stored under refrigeration for catering use. Copyright 2009 Elsevier Ltd. All rights reserved.

Effects of dietary vitamin E supplementation and packaging on the colour stability of sliced pasteurized beef ham.

PubMed

Houben, J H; van Dijk, A

2001-08-01

The effect of supplementation of vitamin E (2025 IU animal(-1) day(-1)) in the diet of beef bulls on the colour stability of pasteurized beef ham was studied. Control and enriched diets were provided for the last 136 days before slaughter. Pasteurized hams were manufactured from Mm. semitendinosus from eight animals per dietary group. Half of the samples of sliced ham from control (CON) and supplemented (SUP) bulls were packaged under vacuum (VAC) and half in low-oxygen modified atmosphere packs (FOG, gas mixture: CO(2)/N(2)=50/50). The packages were kept under constant illumination for 28 days at 8°C. During storage, the number of colony-forming units (CFU) reached a maximum of 5x10(7) g(-1). The microflora was dominated by lactic acid bacteria. The supplementation with vitamin E showed no effect on microbial growth. Lipid oxidation was stable during storage. A significant difference between both dietary groups was detected for the decrease in the redness values during storage. Redness values of CON vacuum-packaged samples decreased (P < 0.01) with time, whereas those for the SUP products only tended to decrease. The redness values of FOG-packed ham were higher than those of VAC-packed ham at the end of the display period, irrespective of the dietary group. Overall, colour appeared to be more stable in the FOG-packed products than in the VAC-packed products. It can be concluded that dietary supplementation of bulls with vitamin E appears to offer only a minor improvement in colour stability over current feeding regimens when the Mm. semitendinosus are used to make cured, pasteurized ham-type products.

Improvements in the shelf life of commercial corn dry masa flour (CMF) by reducing lipid oxidation.

PubMed

Márquez-Castillo, A; Vidal-Quintanar, R L

2011-03-01

To improve the shelf life of commercial nixtamalized corn dry masa flour (CMF), the modified atmosphere packaging (MAP) was used. Pouches (20 × 20 cm) of ethyl vinyl alcohol (EVOH) with 180 g of CMF were stored at 55 °C, and a(w) of 0.45; under Light and Dark conditions, antioxidants (0.02% TBHQ), Vacuum, and N(2) and CO(2), and used as treatments. Thereafter, changes in their linoleic acid (LA) concentration by GC, peroxide (PV), and anisidine values (p-A), which were monitored for 180 d. EVOH showed a significantly lower consumption of LA by autoxidation (11.7% ± 0.2% in 117 d) than polyethylene film (70.5% ± 0.3% in 113 d) under the same storage temperature. The elimination of oxygen by vacuum in each pouch allowed a low consumption (16.4% ± 0.1%) of LA. PV (14.5 ± 0.09 mEq/kg of fat), and p-A (63 ± 0.16 mmol/kg) were low, and generated over 121 d of storage. CMF stored under MAP had 100% protection against oxidation of LA. A combination of Vacuum and EVOH packaging extended the shelf life of CMF to 108 d with only 10% of LA loss. For retail stores, the EVOH packaging will reduce lipid oxidation of CMF and safety related to off odors and flavors from the oxidation of tortillas will increase dramatically.

Effect of type and content of modified montmorillonite on the structure and properties of bio-nanocomposite films based on soy protein isolate and montmorillonite.

PubMed

Kumar, P; Sandeep, K P; Alavi, S; Truong, V D; Gorga, R E

2010-06-01

The nonbiodegradable and nonrenewable nature of plastic packaging has led to a renewed interest in packaging materials based on bio-nanocomposites (biopolymer matrix reinforced with nanoparticles such as layered silicates). Bio-nanocomposite films based on soy protein isolate (SPI) and modified montmorillonite (MMT) were prepared using melt extrusion. The effect of different type (Cloisite 20A and Cloisite 30B) and content (0% to 15%) of modified MMT on the structure (degree of intercalation and exfoliation) and properties (color, mechanical, dynamic mechanical, thermal stability, and water vapor permeability) of SPI-MMT bio-nanocomposite films were investigated. Extrusion of SPI and modified MMTs resulted in bio-nanocomposites with exfoliated structures at lower MMT content (5%). At higher MMT content (15%), the structure of bio-nanocomposites ranged from intercalated for Cloisite 20A to disordered intercalated for Cloisite 30B. At an MMT content of 5%, bio-nanocomposite films based on modified MMTs (Cloisite 20A and Cloisite 30B) had better mechanical (tensile strength and percent elongation at break), dynamic mechanical (glass transition temperature and storage modulus), and water barrier properties as compared to those based on natural MMT (Cloisite Na(+)). Bio-nanocomposite films based on 10% Cloisite 30B had mechanical properties comparable to those of some of the plastics that are currently used in food packaging applications. However, much higher WVP values of these films as compared to those of existing plastics might limit the application of these films to packaging of high moisture foods such as fresh fruits and vegetables.

Fate of Escherichia coli O157:H7, Salmonella and Listeria innocua on minimally-processed peaches under different storage conditions.

PubMed

Alegre, Isabel; Abadias, Maribel; Anguera, Marina; Usall, Josep; Viñas, Inmaculada

2010-10-01

Consumption of fresh-cut produce has sharply increased recently causing an increase of foodborne illnesses associated with these products. As generally, acidic fruits are considered 'safe' from a microbiological point of view, the aim of this work was to study the growth and survival of Escherichia coli O157:H7, Salmonella and Listeria innocua on minimally-processed peaches. The three foodborne pathogens population increased more than 2 log(10)units on fresh-cut peach when stored at 20 and 25 degrees C after 48 h. At 10 degrees C only L. innocua grew more than 1 log(10)unit and it was the only pathogen able to grow at 5 degrees C. Differences in growth occurred between different peach varieties tested, with higher population increases in those varieties with higher pH ('Royal Glory' 4.73+/-0.25 and 'Diana' 4.12+/-0.18). The use of common strategies on extending shelf life of fresh-cut produce, as modified atmosphere packaging and the use of the antioxidant substance, ascorbic acid (2%w/v), did not affect pathogens' growth at any of the temperatures tested (5 and 25 degrees C). Minimally-processed peaches have shown to be a good substrate for foodborne pathogens' growth regardless use of modified atmosphere and ascorbic acid. Therefore, maintaining cold chain and avoiding contamination is highly necessary. 2010 Elsevier Ltd. All rights reserved.

Hot water, UV-C and superatmospheric oxygen packaging as hurdle techniques for maintaining overall quality of fresh-cut pomegranate arils.

PubMed

Maghoumi, Mahshad; Gómez, Perla A; Artés-Hernández, Francisco; Mostofi, Younes; Zamani, Zabihalah; Artés, Francisco

2013-03-30

In recent years there has been increasing consumer pressure to avoid the use of agrochemicals such as chlorine on fresh plant products for extending their shelf life. The combined use of eco-sustainable techniques may be an alternative. The effect of hot water (HW), ultraviolet-C (UV-C) light and high oxygen packaging (HO) on the overall quality of fresh-cut pomegranate arils stored under modified atmosphere packaging (MAP) for up to 14 days at 5 °C was studied. Arils extracted manually, washed with chlorine (100 µL L⁻¹ NaClO, pH 6.5, 5 °C water), rinsed and drained were exposed to single or combined (double and triple) hurdle techniques. The HW treatment consisted of a 30 s immersion in water at 55 °C followed by air surface drying. A 4.54 kJ m⁻² dose was used for the UV-C treatment before packaging. Active MAP with initial 90 kPa O₂ was used in the HO treatment. The respiration rate remained relatively constant throughout shelf life, with no differences among treatments. CO₂ accumulation was higher within HO packages. HW induced a slight reduction in total soluble solids, while no changes in titratable acidity were found. HO-treated arils had the highest phenolic content, while the lowest was found in HW-treated arils. The lowest antioxidant activity was found in HW + UV-C + HO and the highest in UV-C + HO and HO treatments. HW alone or in combination with UV-C and HO inhibited mesophile, mould and yeast growth, while UV-C + HO was most effective for controlling yeast and mould growth. UV-C and HO either alone or in combination are promising techniques to preserve the quality of pomegranate arils for up to 14 days at 5 °C. © 2012 Society of Chemical Industry.

Python-based dynamic scheduling assistant for atmospheric measurements by Bruker instruments using OPUS.

PubMed

Geddes, Alexander; Robinson, John; Smale, Dan

2018-02-01

Atmospheric remote sensing by instruments such as spectrometers and interferometers often requires scheduling that is dependent on external factors, for example; time and solar (or lunar) zenith angle. Such instruments manufactured by Bruker often use the software package OPUS, which, while useful, is not flexible enough for automatic, repeated, atmospheric measurements of this nature. In this brief paper, we describe ASAP, a Python tool developed to run our network of Fourier transform interferometers in New Zealand and Antarctica. It allows the automated scheduling of measurements by time, lunar, or solar zenith angle while accounting for weather or other external parameters. There is a wide range of useful functions, all packaged in a simple graphical user interface; it is available on request.

Computer program documentation modified version of the JA70 aerodynamic heating computer program H800 (MINIVER with a DISSPLA plot package

NASA Technical Reports Server (NTRS)

Olmedo, L.

1980-01-01

The changes, modifications, and inclusions which were adapted to the current version of the MINIVER program are discussed. Extensive modifications were made to various subroutines, and a new plot package added. This plot package is the Johnson Space Center DISSPLA Graphics System currently driven under an 1110 EXEC 8 configuration. User instructions on executing the MINIVER program are provided and the plot package is described.

Variations in algorithm implementation among quantitative texture analysis software packages

NASA Astrophysics Data System (ADS)

Foy, Joseph J.; Mitta, Prerana; Nowosatka, Lauren R.; Mendel, Kayla R.; Li, Hui; Giger, Maryellen L.; Al-Hallaq, Hania; Armato, Samuel G.

2018-02-01

Open-source texture analysis software allows for the advancement of radiomics research. Variations in texture features, however, result from discrepancies in algorithm implementation. Anatomically matched regions of interest (ROIs) that captured normal breast parenchyma were placed in the magnetic resonance images (MRI) of 20 patients at two time points. Six first-order features and six gray-level co-occurrence matrix (GLCM) features were calculated for each ROI using four texture analysis packages. Features were extracted using package-specific default GLCM parameters and using GLCM parameters modified to yield the greatest consistency among packages. Relative change in the value of each feature between time points was calculated for each ROI. Distributions of relative feature value differences were compared across packages. Absolute agreement among feature values was quantified by the intra-class correlation coefficient. Among first-order features, significant differences were found for max, range, and mean, and only kurtosis showed poor agreement. All six second-order features showed significant differences using package-specific default GLCM parameters, and five second-order features showed poor agreement; with modified GLCM parameters, no significant differences among second-order features were found, and all second-order features showed poor agreement. While relative texture change discrepancies existed across packages, these differences were not significant when consistent parameters were used.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bradbury, Andrew M.

The invention relates to a novel phagemid display system for packaging phagemid DNA into phagemid particles which completely avoids the use of helper phage. The system of the invention incorporates the use of bacterial packaging cell lines which have been transformed with helper plasmids containing all required phage proteins but not the packaging signals. The absence of packaging signals in these helper plasmids prevents their DNA from being packaged in the bacterial cell, which provides a number of significant advantages over the use of both standard and modified helper phage. Packaged phagemids expressing a protein or peptide of interest, inmore » fusion with a phage coat protein such as g3p, are generated simply by transfecting phagemid into the packaging cell line.« less

Installation package for concentrating solar collector panels

NASA Technical Reports Server (NTRS)

1978-01-01

The concentrating solar collector panels comprise a complete package array consisting of collector panels using modified Fresnel prismatic lenses for a 10 to 1 concentrating ratio, supporting framework, fluid manifolding and tracking drive system, and unassembled components for field erection.

Food packaging history and innovations.

PubMed

Risch, Sara J

2009-09-23

Food packaging has evolved from simply a container to hold food to something today that can play an active role in food quality. Many packages are still simply containers, but they have properties that have been developed to protect the food. These include barriers to oxygen, moisture, and flavors. Active packaging, or that which plays an active role in food quality, includes some microwave packaging as well as packaging that has absorbers built in to remove oxygen from the atmosphere surrounding the product or to provide antimicrobials to the surface of the food. Packaging has allowed access to many foods year-round that otherwise could not be preserved. It is interesting to note that some packages have actually allowed the creation of new categories in the supermarket. Examples include microwave popcorn and fresh-cut produce, which owe their existence to the unique packaging that has been developed.

Superchilling of muscle foods: Potential alternative for chilling and freezing.

PubMed

Banerjee, Rituparna; Maheswarappa, Naveena Basappa

2017-12-05

Superchilling is an attractive technique for preservation of muscle foods which freezes part of the water and insulate the food products from temperature fluctuations thereby enhancing the shelf-life during storage, transportation and retailing. Superchilling process synergistically improves the product shelf-life when used in combination with vacuum or modified atmospheric packaging. The shelf-life of muscle foods was reported to be increased by 1.5 to 4.0 times relative to traditional chilling technique. Advantages of superchilling and its ability to maintain the freshness of muscle foods over freezing has been discussed and its potential for Industrial application is highlighted. Present review also unravel the mechanistic bases for ice-crystal formation during superchilling and measures to ameliorate the drip loss. The future challenges especially automation in superchilling process for large scale Industrial application is presented.

Impact of freezing and thawing on the quality of meat: review.

PubMed

Leygonie, Coleen; Britz, Trevor J; Hoffman, Louwrens C

2012-06-01

This comprehensive review describes the effects of freezing and thawing on the physical quality parameters of meat. The formation of ice crystals during freezing damages the ultrastructure and concentrates the solutes in the meat which, in turn, leads to alterations in the biochemical reactions that occur at the cellular level and influence the physical quality parameters of the meat. The quality parameters that were evaluated are moisture loss, protein denaturation, lipid and protein oxidation, colour, pH, shear force and microbial spoilage. Additionally mechanisms employed to mitigate the effects of freezing and thawing were also reviewed. These include the use of novel methods of freezing and thawing, ante and post mortem antifreeze protein inclusion and vitamin E supplementation, brine injection and modified atmospheric packaging. Copyright © 2012 Elsevier Ltd. All rights reserved.

49 CFR 173.33 - Hazardous materials in cargo tank motor vehicles.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SHIPPERS-GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS Preparation of Hazardous Materials for... excess of ambient atmospheric pressure may not be used to load or unload any lading which may create an... tank motor vehicle having a MAWP of 25 psig or greater. (6) Substitute packagings. Unless otherwise...

Learning Activity Package, Physical Science 92, LAPs 1-9.

ERIC Educational Resources Information Center

Williams, G. J.

This set of nine teacher-prepared Learning Activity Packages (LAPs) for individualized instruction in physical science covers the topics of scientific equipment and procedures; measure of time, length, area, and volume; water; oxygen and oxidation; atmospheric pressure; motion; machines; carbon; and light and sound. Each unit contains a rationale…

Packaging material and flexible medical tubing containing thermally exfoliated graphite oxide

NASA Technical Reports Server (NTRS)

Prud'homme, Robert K. (Inventor); Aksay, Ilhan A. (Inventor)

2011-01-01

A packaging material or flexible medical tubing containing a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m.sup.2/g to 2600 m.sup.2/g.

Earth Global Reference Atmospheric Model (GRAM) Overview and Updates: DOLWG Meeting

NASA Technical Reports Server (NTRS)

White, Patrick

2017-01-01

What is Earth-GRAM (Global Reference Atmospheric Model): Provides monthly mean and standard deviation for any point in atmosphere - Monthly, Geographic, and Altitude Variation; Earth-GRAM is a C++ software package - Currently distributed as Earth-GRAM 2016; Atmospheric variables included: pressure, density, temperature, horizontal and vertical winds, speed of sound, and atmospheric constituents; Used by engineering community because of ability to create dispersions in atmosphere at a rapid runtime - Often embedded in trajectory simulation software; Not a forecast model; Does not readily capture localized atmospheric effects.

Oregano essential oil-based natural antimicrobial packaging film to inactivate Salmonella enterica and yeasts/molds in the atmosphere surrounding cherry tomatoes.

PubMed

Kwon, Sang-Jo; Chang, Yoonjee; Han, Jaejoon

2017-08-01

This study investigated the effectiveness of a polyvinyl alcohol (PVA) film containing the natural antimicrobial oregano essential oil (OEO) as an active packaging application for decreasing the microbial growth. The film exerted an antimicrobial effect via the atmosphere surrounding the food rather than direct contact, thereby preserving the quality of cherry tomatoes. A packaging film containing microencapsulated OEO was developed. The loading content increased gradually (104.29-234.29 μg OEO/mg film) with the amount of OEO incorporated (1%, 2%, and 3%), where the PVA films containing 2% OEO had the highest loading efficiency (91.64%), followed by 1% OEO (90.96%) and 3% OEO (88.38%). The antimicrobial activities of the films were evaluated by applying it to fresh cherry tomatoes at 4 °C and 22 °C for 7 days. The large 2% OEO film as well as both the small and large 3% OEO films had strong antimicrobial effects against Salmonella enterica, molds and yeasts, and mesophilic aerobic bacteria. The changes in the hardness, weight, and color of the cherry tomatoes during storage did not differ significantly. The films could be utilized as a packaging material for fresh produce with antimicrobial effects because of the controlled atmosphere surrounding the food rather than by direct contact. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antagonistic effect of Pseudomonas graminis CPA-7 against foodborne pathogens in fresh-cut apples under simulated commercial conditions.

PubMed

Alegre, Isabel; Viñas, Inmaculada; Usall, Josep; Anguera, Marina; Altisent, Rosa; Abadias, Maribel

2013-04-01

Recently, we reported that the application of the strain CPA-7 of Pseudomonas graminis, previously isolated from apple, could reduce the population of foodborne pathogens on minimally processed (MP) apples and peaches under laboratory conditions. Therefore, the objective of the present work was to find an antioxidant treatment and a packaging atmosphere condition to improve CPA-7 efficacy in reducing a cocktail of four Salmonella and five Listeria monocytogenes strains on MP apples under simulated commercial processing. The effect of CPA-7 application on apple quality and its survival to simulated gastric stress were also evaluated. Ascorbic acid (2%, w/v) and N-acetyl-l-cysteine (1%, w/v) as antioxidant treatments reduced Salmonella, L. monocytogenes and CPA-7 recovery, meanwhile no reduction was observed with NatureSeal(®) AS1 (NS, 6%, w/v). The antagonistic strain was effective on NS-treated apple wedges stored at 10 °C with or without modified atmosphere packaging (MAP). Then, in a semi-commercial assay, efficacy of CPA-7 inoculated at 10(5) and 10(7) cfu mL(-1) against Salmonella and L. monocytogenes strains on MP apples with NS and MAP and stored at 5 and 10 °C was evaluated. Although high CPA-7 concentrations/populations avoided Salmonella growth at 10 °C and lowered L. monocytogenes population increases were observed at both temperatures, the effect was not instantaneous. No effect on apple quality was detected and CPA-7 did not survived to simulated gastric stress throughout storage. Therefore, CPA-7 could avoid pathogens growth on MP apples during storage when use as part of a hurdle technology in combination with disinfection techniques, low storage temperature and MAP. Copyright © 2012 Elsevier Ltd. All rights reserved.

Design and Development of a CPCI-Based Electronics Package for Space Station Experiments

NASA Technical Reports Server (NTRS)

Kolacz, John S.; Clapper, Randy S.; Wade, Raymond P.

2006-01-01

The NASA John H. Glenn Research Center is developing a Compact-PCI (CPCI) based electronics package for controlling space experiment hardware on the International Space Station. Goals of this effort include an easily modified, modular design that allows for changes in experiment requirements. Unique aspects of the experiment package include a flexible circuit used for internal interconnections and a separate enclosure (box in a box) for controlling 1 kW of power for experiment fuel heating requirements. This electronics package was developed as part of the FEANICS (Flow Enclosure Accommodating Novel Investigations in Combustion of Solids) mini-facility which is part of the Fluids and Combustion Facility s Combustion Integrated Rack (CIR). The CIR will be the platform for future microgravity combustion experiments and will reside on the Destiny Module of the International Space Station (ISS). The FEANICS mini-facility will be the primary means for conducting solid fuel combustion experiments in the CIR on ISS. The main focus of many of these solid combustion experiments will be to conduct applied scientific investigations in fire-safety to support NASA s future space missions. A description of the electronics package and the results of functional testing are the subjects of this report. The report concludes that the use of innovative packaging methods combined with readily available COTS hardware can provide a modular electronics package which is easily modified for changing experiment requirements.

Earth Global Reference Atmospheric Model (Earth-GRAM) GRAM Virtual Meeting

NASA Technical Reports Server (NTRS)

White, Patrick

2017-01-01

What is Earth-GRAM? Provide monthly mean and standard deviation for any point in atmosphere; Monthly, Geographic, and Altitude Variation. Earth-GRAM is a C++ software package; Currently distributed as Earth-GRAM 2016. Atmospheric variables included: pressure, density, temperature, horizontal and vertical winds, speed of sound, and atmospheric constituents. Used by engineering community because of ability to create dispersions inatmosphere at a rapid runtime; Often embedded in trajectory simulation software. Not a forecast model. Does not readily capture localized atmospheric effects.

Towards a Comprehensive Dynamic-chemistry Assimilation for Eos-Chem: Plans and Status in NASA's Data Assimilation Office

NASA Technical Reports Server (NTRS)

Pawson, Steven; Lin, Shian-Jiann; Rood, Richard B.; Stajner, Ivanka; Nebuda, Sharon; Nielsen, J. Eric; Douglass, Anne R.

2000-01-01

In order to support the EOS-Chem project, a comprehensive assimilation package for the coupled chemical-dynamical system is being developed by the Data Assimilation Office at NASA GSFC. This involves development of a coupled chemistry/meteorology model and of data assimilation techniques for trace species and meteorology. The model is being developed using the flux-form semi-Lagrangian dynamical core of Lin and Rood, the physical parameterizations from the NCAR Community Climate Model, and atmospheric chemistry modules from the Atmospheric Chemistry and Dynamics branch at NASA GSFC. To date the following results have been obtained: (i) multi-annual simulations with the dynamics-radiation model show the credibility of the package for atmospheric simulations; (ii) initial simulations including a limited number of middle atmospheric trace gases reveal the realistic nature of transport mechanisms, although there is still a need for some improvements. Samples of these results will be shown. A meteorological assimilation system is currently being constructed using the model; this will form the basis for the proposed meteorological/chemical assimilation package. The latter part of the presentation will focus on areas targeted for development in the near and far terms, with the objective of Providing a comprehensive assimilation package for the EOS-Chem science experiment. The first stage will target ozone assimilation. The plans also encompass a reanalysis (ReSTS) for the 1991-1995 period, which includes the Mt. Pinatubo eruption and the time when a large number of UARS observations were available. One of the most challenging aspects of future developments will be to couple theoretical advances in tracer assimilation with the practical considerations of a real environment and eventually a near-real-time assimilation system.

PEG-template for surface modification of zeolite: A convenient material to the design of polypropylene based composite for packaging films

NASA Astrophysics Data System (ADS)

Toommee, S.; Pratumpong, P.

2018-06-01

Zeolite was successfully modified by conventional synthetic route. Polyethylene glycol was employed for surface modification of zeolite. The surface of zeolite exhibited therefore hydrophobic properties. Less than 5 wt% of modified zeolites with uniform size and shape were integrated into polypropylene matrix. Mechanical properties of composite exhibited the similar trend compare to neat polypropylene. Oxygen transmission rate and water vapor transmission rate were evaluated and it exhibited the strong potential to be a good candidate material in active packaging.

Effect of Oxygen-Reducing Atmospheres on the Safety of Packaged Shelled Brazil Nuts during Storage

PubMed Central

Scussel, Vildes Maria; Giordano, Barbara Nantua; Simao, Vanessa; Manfio, Daniel; Galvao, Simone; Rodrigues, Manuel Nazaré Ferreira

2011-01-01

This work reports the application of oxygen-(O2-) reducing atmosphere methods on stored shelled Brazil nut (Bertholletia excelsa H.B.K.) packs aiming to evaluate the degree of aflatoxin degradation, nuts lipid oxidative stability, fungi control, and hygienic conditions improvement. The methods applied were (a) ozone: O3, (b) carbon dioxide: CO2, and (c) O2 absorber pads with and without vacuum. From all modified atmospheres evaluated, the best performance was obtained with O3, either with or without vacuum. It was the only nut treatment that was able to degrade aflatoxins. None of the spiked (AFLs: 15 μg·kg−1) nut samples O3- treated had aflatoxins detected up to the LC-MS/MS method LOQ (0.36 μg·kg−1 for total AFLs), thus producing safer nuts. Also it kept the fatty acid oxidation indicator—malondialdehyde stable and improved the sensory attributes for consumer acceptance. In addition, the destruction of fungi and yeast was observed since the O3 application (from 1.8 × 104 cfu/g to NG = no growth). All other treatments stabilized and/or inhibited microorganisms' growth only. By adding CO2 gas also played an important role in the nut quality. Regarding cost, gaseous O3 showed to be of low cost for application in the nut packs. PMID:21760791

The impact of enterocin AS-48 on the shelf-life and safety of sardines (Sardina pilchardus) under different storage conditions.

PubMed

Ananou, S; Zentar, H; Martínez-Bueno, M; Gálvez, A; Maqueda, M; Valdivia, E

2014-12-01

The purpose of this study was to determine the effect of enterocin AS-48, packaged under normal atmosphere (NA), vacuum (VP) or modified atmosphere (MAP) on the shelf life and safety of fresh sardines (Sardina pilchardus) stored at 5 °C. We studied the effect of these hurdles, alone or combined, on the relevant autochthonous bacterial populations. Total volatile basic nitrogen (TVB-N) content was used as indicative of freshness. Levels of biogenic amines cadaverine, putrescine, tyramine, and histamine were also determined. The application of AS-48 did not reduce the mesophilic, psychrotrophic, or Gram negative bacteria viable cell counts under any of the storage conditions tested. AS-48 did cause significant reductions in viable staphylococci counts, especially under VP. In sardines under NA treated with AS-48, the populations of histamine- and tyramine-forming total and lactic acid bacteria (LAB) showed no significant reductions. MAP or VP with AS-48 allowed reductions (significant at some storage times) in histamine- and tyramine-forming LAB. The TVB-N content was also reduced under normal atmosphere and, especially, in sardines stored under MAP. The most interesting results are those concerning the decrease (by several fold) in the levels of the biogenic amines cadaverine, putrescine, tyramine, and histamine determined after treatment with AS-48. Copyright © 2014 Elsevier Ltd. All rights reserved.

In-package inhibition of E. Coli 0157:H7 on bulk Romaine lettuce using cold plasma

USDA-ARS?s Scientific Manuscript database

Dielectric barrier discharge atmospheric cold plasma (ACP) has been investigated as an innovative method for in-package decontamination of fresh produce. However, while data is available for treatment of single leaves, data is lacking for the effect of ACP on the microbial decontamination of bulk le...

pyhector: A Python interface for the simple climate model Hector

DOE Office of Scientific and Technical Information (OSTI.GOV)

N Willner, Sven; Hartin, Corinne; Gieseke, Robert

2017-04-01

Pyhector is a Python interface for the simple climate model Hector (Hartin et al. 2015) developed in C++. Simple climate models like Hector can, for instance, be used in the analysis of scenarios within integrated assessment models like GCAM1, in the emulation of complex climate models, and in uncertainty analyses. Hector is an open-source, object oriented, simple global climate carbon cycle model. Its carbon cycle consists of a one pool atmosphere, three terrestrial pools which can be broken down into finer biomes or regions, and four carbon pools in the ocean component. The terrestrial carbon cycle includes primary production andmore » respiration fluxes. The ocean carbon cycle circulates carbon via a simplified thermohaline circulation, calculating air-sea fluxes as well as the marine carbonate system (Hartin et al. 2016). The model input is time series of greenhouse gas emissions; as example scenarios for these the Pyhector package contains the Representative Concentration Pathways (RCPs)2. These were developed to cover the range of baseline and mitigation emissions scenarios and are widely used in climate change research and model intercomparison projects. Using DataFrames from the Python library Pandas (McKinney 2010) as a data structure for the scenarios simplifies generating and adapting scenarios. Other parameters of the Hector model can easily be modified when running the model. Pyhector can be installed using pip from the Python Package Index.3 Source code and issue tracker are available in Pyhector's GitHub repository4. Documentation is provided through Readthedocs5. Usage examples are also contained in the repository as a Jupyter Notebook (Pérez and Granger 2007; Kluyver et al. 2016). Courtesy of the Mybinder project6, the example Notebook can also be executed and modified without installing Pyhector locally.« less

Flame resistant elastomeric polymer development. [for use in space shuttle instrument packaging

NASA Technical Reports Server (NTRS)

Howarth, J. T.; Sheth, S. G.; Sidman, K. R.

1975-01-01

Elastomeric products were developed for use in the space shuttle program, and investigations were conducted to improve the properties of elastomers developed in previous programs, and to evaluate the possibility of using lower-cost general purpose polymers. Products were fabricated and processed on conventional processing equipment; these products include: foams based on fluorinated rubber flame-retarded compounds with a density of 20-30 pounds/cubic foot for use as padding and in helmets; foams based on urethane for use in instrument packaging in the space shuttle; flexible and semi-rigid films of fluorinated rubber and neoprene compounds that would not burn in a 70% nitrogen, 30% oxygen atmosphere, and in a 30% nitrogen, 70% oxygen atmosphere, respectively for use in packaging or in laminates; coated fabrics which used both nylon and Kelvar fabric substrates, coated with either fluorinated or neoprene polymer compositions to meet specific levels of flame retardancy; and other flame-resistant materials.

Experiments with a Regional Vector-Vorticity Model, and Comparison with Other Models

NASA Astrophysics Data System (ADS)

Konor, C. S.; Dazlich, D. A.; Jung, J.; Randall, D. A.

2017-12-01

The Vector-Vorticity Model (VVM) is an anelastic model with a unique dynamical core that predicts the three-dimensional vorticity instead of the three-dimensional momentum. The VVM is used in the CRMs of the Global Quasi-3D Multiscale Modeling Framework, which is discussed by Joon-Hee Jung and collaborators elsewhere in this session. We are updating the physics package of the VVM, replacing it with the physics package of the System for Atmosphere Modeling (SAM). The new physics package includes a double-moment microphysics, Mellor-Yamada turbulence, Monin-Obukov surface fluxes, and the RRTMG radiation parameterization. We briefly describe the VVM and show results from standard test cases, including TWP-ICE. We compare the results with those obtained using the earlier physics. We also show results from experiments on convection aggregation in radiative-convective equilibrium, and compare with those obtained using both SAM and the Regional Atmospheric Modeling System (RAMS).

[Effect of heat transfer in the packages on the stability of thiamine nitrate under uncontrolled temperature conditions].

PubMed

Nakamura, Toru; Yamaji, Takayuki; Takayama, Kozo

2013-01-01

To accurately predict the stability of thiamine nitrate as a model drug in pharmaceutical products under uncontrolled temperature conditions, the average reaction rate constant was determined, taking into account the heat transfer from the atmosphere to the product. The stability tests of thiamine nitrate in the three packages with different heat transfers were performed under non-isothermal conditions. The stability data observed were compared with the predictions based on a newly developed method, showing that the stability was well predicted by the method involving the heat transfer. By contrast, there were some deviations observed from the predicted data, without considering heat transfer in the packages with low heat transfer. The above-mentioned result clearly shows that heat transfer should be considered to ensure accurate prediction of the stability of commercial pharmaceutical products under non-isothermal atmospheres.

Influence of modified atmosphere and ethylene levels on quality attributes of fresh tomatoes (Lycopersicon esculentum Mill.).

PubMed

Domínguez, Irene; Lafuente, María T; Hernández-Muñoz, Pilar; Gavara, Rafael

2016-10-15

Controlling storage atmosphere is a key factor for delaying postharvest fruit quality loss. The objective of this study is to evaluate its influence on physico-chemical, sensorial and nutritional quality attributes of two tomato fruit cultivars (Delizia and Pitenza) that respectively have a short- and long-storage life. To that end, the effect of two types of bags with different gas permeability, combined or not with an ethylene sorbent, on tomato organoleptic and nutritional properties were compared during fruit storage at 13°C. CO2 and O2 were critical factors for controlling tomato postharvest behaviour. Weight loss, firmness, color and visual quality were only affected by bag permeability just as total sugar content and acidity for Pitenza tomatoes. (trans)-2-Hexenal also appears to be related with CO2 and O2 levels. Lycopene, total phenols (TP) and ascorbic acid (AA) contents were also affected by the packaging form and the storage length. Ethylene removal in combination with MAP led to a higher content in TP and AA in the short-life tomato cultivar. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbiological, chemical and sensory spoilage analysis of raw Atlantic cod (Gadus morhua) stored under modified atmospheres.

PubMed

Kuuliala, L; Al Hage, Y; Ioannidis, A-G; Sader, M; Kerckhof, F-M; Vanderroost, M; Boon, N; De Baets, B; De Meulenaer, B; Ragaert, P; Devlieghere, F

2018-04-01

During fish spoilage, microbial metabolism leads to the production of volatile organic compounds (VOCs), characteristic off-odors and eventual consumer rejection. The aim of the present study was to contribute to the development of intelligent packaging technologies by identifying and quantifying VOCs that indicate spoilage of raw Atlantic cod (Gadus morhua) under atmospheres (%v/v CO 2 /O 2 /N 2 ) 60/40/0, 60/5/35 and air. Spoilage was examined by microbiological, chemical and sensory analyses over storage time at 4 or 8 °C. Selected-ion flow-tube mass spectrometry (SIFT-MS) was used for quantifying selected VOCs and amplicon sequencing of the 16S rRNA gene was used for the characterization of the cod microbiota. OTUs classified within the Photobacterium genus increased in relative abundance over time under all storage conditions, suggesting that Photobacterium contributed to spoilage and VOC production. The onset of exponential VOC concentration increase and sensory rejection occurred at high total plate counts (7-7.5 log). Monitoring of early spoilage thus calls for sensitivity for low VOC concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Validation and calibration of a TDLAS oxygen sensor for in-line measurement on flow-packed products

NASA Astrophysics Data System (ADS)

Cocola, L.; Fedel, M.; Allermann, H.; Landa, S.; Tondello, G.; Bardenstein, A.; Poletto, L.

2016-05-01

A device based on Tunable Diode Laser Absorption Spectroscopy has been developed for non-invasive evaluation of gaseous oxygen concentration inside packed food containers. This work has been done in the context of the SAFETYPACK European project in order to enable full, automated product testing on a production line. The chosen samples at the end of the manufacturing process are modified atmosphere bags of processed mozzarella, in which the target oxygen concentration is required to be below 5%. The spectrometer allows in-line measurement of moving samples which are passing on a conveyor belt, with an optical layout optimized for bags made of a flexible scattering material, and works by sensing the gas phase in the headspace at the top of the package. A field applicable method for the calibration of this device has been identified and validated against traditional, industry standard, invasive measurement techniques. This allows some degrees of freedom for the end-user regarding packaging dimensions and shape. After deployment and setup of the instrument at the end-user manufacturing site, performance has been evaluated on a different range of samples in order to validate the choice of electro optical and geometrical parameters regarding sample handling and measurement timing at the actual measurement conditions.

Quality assessment of salted, modified atmosphere packaged rainbow trout under treatment with oregano essential oil.

PubMed

Pyrgotou, Nikoletta; Giatrakou, Vasiliki; Ntzimani, Athina; Savvaidis, Ioannis N

2010-09-01

The present study evaluated the effect of oregano essential oil (EO) on fresh salted, packaged (45%CO(2)/5%O(2)/50%N(2)) rainbow trout fillets and stored for a period of 21 d at 4 °C. Treatments included the following: M1 (control without added EO), M2 (EO 0.2%, v/w), and M3 (0.4%, v/w). Populations of lactic acid bacteria (LAB), H(2)S-producing bacteria (including Shewanella putrefaciens), Enterobacteriaceae, and Pseudomonas spp. reached higher final numbers in control (M1) than for M2 and M3 samples. Under treatments M2 and M3, total volatile basic nitrogen (TVBN) and trimethylamine nitrogen (TMAN) values were lower than for M1 samples, whereas lipid oxidation, as judged by determination of thiobarbituric acid values (TBA), did not occur during the refrigerated storage period. Interestingly, treatment M2 resulted in a shelf-life extension of 7 to 8 d for the fresh trout fillets, whereas treatment M3 proved unsuitable (due to strong odor) for trout fillet preservation, as determined by sensory evaluation. The use of an essential oil such as oregano oil in fresh fish preservation may be considered an alternative "natural" additive, enhancing the sensory characteristics and extending the shelf life of the product.

Trans Atlantic Infrasound Payload (TAIP) Operation Plan.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bowman, Daniel; Lees, Jonathan M.

The Carolina Infrasound package, added as a piggyback to the 2016 ULDB ight, recorded unique acoustic signals such as the ocean microbarom and a large meteor. These data both yielded unique insights into the acoustic energy transfer from the lower to the upper atmosphere as well as highlighted the vast array of signals whose origins remain unknown. Now, the opportunity to y a payload across the north Atlantic offers an opportunity to sample one of the most active ocean microbarom sources on Earth. Improvements in payload capabilities should result in characterization of the higher frequency range of the stratospheric infrasoundmore » spectrum as well. Finally, numerous large mining and munitions disposal explosions in the region may provide \\ground truth" events for assessing the detection capability of infrasound microphones in the stratosphere. The flight will include three different types of infrasound sensors. One type is a pair of polarity reversed InfraBSU microphones (standard for high altitude flights since 2016), another is a highly sensitive Chaparral 60 modified for a very low corner period, and the final sensor is a lightweight, low power Gem infrasound package. By evaluating these configurations against each other on the same flight, we will be able to optimize future campaigns with different sensitivity and mass constraints.« less

Meat Quality Derived from High Inclusion of a Micro-Alga or Insect Meal as an Alternative Protein Source in Poultry Diets: A Pilot Study

PubMed Central

Neumann, Carmen; Velten, Susanne; Liebert, Frank

2018-01-01

The effects on meat quality resulting from alternative dietary protein sources (Spirulina and Hermetia meal) in poultry diets are studied to determine the overall suitability of these ingredients considering state-of-the-art packaging practices—highly oxygenated modified atmosphere packaging (HiOx MAP). We monitored standard slaughterhouse parameters, such as live weight, carcass weight, dressed yield, and pH at 20 min and 24 h post mortem. In addition, we studied the effects that 3 and 7-day storage in HiOx MAP has on the overall product physico-chemical and sensory properties. In addition to previously supported effects of HiOx MAP, we found that meat quality could be improved when Spirulina replaces 50% of the soy protein in broiler diets; however, this substitution results in a dark reddish-yellowish meat colour. On the other hand, the substitution with Hermetia larval meal results in a product that does not differ from the standard fed control group, with the exception that the breast filet has a more intense flavour that decreases over storage time. All-in-all Spirulina and Hermetia meal have the potential to replace soybean meal in broiler diets without deteriorating meat quality. PMID:29518048

Thyme Oil Encapsulated in Halloysite Nanotubes for Antimicrobial Packaging System.

PubMed

Lee, Min Hyeock; Seo, Hyun-Sun; Park, Hyun Jin

2017-04-01

An antimicrobial capsule releasing thyme oil was developed using modified halloysite nanotubes (HNTs). In order to increase the pore volume, HNTs were treated with 5.0 mol/L NaOH solution, which resulted in the encapsulation of more thyme oil molecules inside the HNTs. The morphology of the raw HNTs and NaOH-treated HNTs (N-HNTs) was characterized using transmission electron microscopy and nitrogen adsorption-desorption analysis. The loading capacity increased from 180.7 ± 12.7 to 256.4 ± 16.7 mg thyme oil/g HNT after the NaOH treatment. The aerial release characteristics of thyme oil from both the HNT capsules were investigated in a closed-package atmosphere system at 4, 25, and 40 °C. The antimicrobial activity of the capsule against Escherichia coli O157:H7 was determined using the vapor phase assay. Moreover, the antimicrobial effects of the capsule against E. coli O157:H7, total mesophilic aerobic bacteria (MAB), and molds and yeasts (MY) on the surfaces of cherry tomatoes were investigated at 4 and 25 °C for 5 d. When the cherry tomatoes were exposed to the thyme oil-loaded N-HNT capsule, the number of E. coli O157:H7, MAB, and MY significantly reduced during storage. © 2017 Institute of Food Technologists®.

Compact, Engineered 2-Micron Coherent Doppler Wind Lidar Prototype for Field and Airborne Evaluation

NASA Technical Reports Server (NTRS)

Kavaya, Michael J.; Amzajerdian, Farzin; Koch, Grady J.

2006-01-01

The state-of-the-art 2-micron coherent Doppler wind lidar breadboard at NASA/LaRC will be engineered and compactly packaged consistent with future aircraft flights. The packaged transceiver will be integrated into a coherent Doppler wind lidar system test bed at LaRC. Atmospheric wind measurements will be made to validate the packaged technology. This will greatly advance the coherent part of the hybrid Doppler wind lidar solution to the need for global tropospheric wind measurements.

In Situ Atmospheric Pressure Measurements in the Martian Southern Polar Region: Mars Volatiles and Climate Surveyor Meteorology Package on the Mars Polar Lander

NASA Technical Reports Server (NTRS)

Harri, A.-M.; Polkko, J.; Siili, T.; Crisp, D.

1998-01-01

Pressure observations are crucial for the success of the Mars Volatiles and Climate Surveyor (MVACS) Meteorology (MET) package onboard the Mars Polar Lander (MPL), due for launch early next year. The spacecraft is expected to land in December 1999 (L(sub s) = 256 degrees) at a high southern latitude (74 degrees - 78 degrees S). The nominal period of operation is 90 sols but may last up to 210 sols. The MVACS/MET experiment will provide the first in situ observations of atmospheric pressure, temperature, wind, and humidity in the southern hemisphere of Mars and in the polar regions. The martian atmosphere goes through a large-scale atmospheric pressure cycle due to the annual condensation/sublimation of the atmospheric CO2. Pressure also exhibits short period variations associated with dust storms, tides, and other atmospheric events. A series of pressure measurements can hence provide us with information on the large-scale state and dynamics of the atmosphere, including the CO2 and dust cycles as well as local weather phenomena. The measurements can also shed light on the shorter time scale phenomena (e.g., passage of dust devils) and hence be important in contributing to our understanding of mixing and transport of heat, dust, and water vapor.

49 CFR 173.320 - Cryogenic liquids; exceptions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... atmospheric gases and helium: (1) During loading and unloading operations (pressure rises may exceed 25.3 psig...; exceptions. (a) Atmospheric gases and helium, cryogenic liquids, in Dewar flasks, insulated cylinders... the pressure in such packagings will not exceed 25.3 psig under ambient temperature conditions during...

Shuttle high resolution accelerometer package experiment results - Atmospheric density measurements between 60-160 km

NASA Technical Reports Server (NTRS)

Blanchard, R. C.; Hinson, E. W.; Nicholson, J. Y.

1988-01-01

Indirect or inferred values of atmospheric density encountered by the Shuttle Orbiter during reentry have been calculated from acceleration measurements made by the High Resolution Accelerometer Package (HiRAP) and the Orbiter Inertial Measurement Unit (IMU) liner accelerometers. The atmospheric density data developed from this study represent a significant gain with respect to the body of data collected to date by various techniques in the altitude range of 60 to 160 km. The data are unique in that they cover a very wide horizontal range during each flight and provide insight into the actual density variations encountered along the reentry flight path. The data, which were collected over about 3 years, are also characterized by variations in solar activity, geomagnetic index, and local solar time. Comparison of the flight-derived densities with various atmospheric models have been made, and analyses have attempted to characterize the data and to show correlation with selected physical variables.

ULFEM time series analysis package

USGS Publications Warehouse

Karl, Susan M.; McPhee, Darcy K.; Glen, Jonathan M. G.; Klemperer, Simon L.

2013-01-01

This manual describes how to use the Ultra-Low-Frequency ElectroMagnetic (ULFEM) software package. Casual users can read the quick-start guide and will probably not need any more information than this. For users who may wish to modify the code, we provide further description of the routines.

Cast Glance Near Infrared Imaging Observations of the Space Shuttle During Hypersonic Re-Entry

NASA Technical Reports Server (NTRS)

Tack, Steve; Tomek, Deborah M.; Horvath, Thomas J.; Verstynen, Harry A.; Shea, Edward J.

2010-01-01

High resolution calibrated infrared imagery of the Space Shuttle was obtained during hypervelocity atmospheric entries of the STS-119, STS-125 and STS128 missions and has provided information on the distribution of surface temperature and the state of the airflow over the windward surface of the Orbiter during descent. This data collect was initiated by NASA s Hypersonic Thermodynamic Infrared Measurements (HYTHIRM) team and incorporated the use of air- and land-based optical assets to image the Shuttle during atmospheric re-entry. The HYTHIRM objective is to develop and implement a set of mission planning tools designed to establish confidence in the ability of an existing optical asset to reliably acquire, track and return global quantitative surface temperatures of the Shuttle during entry. On Space Shuttle Discovery s STS-119 mission, NASA flew a specially modified thermal protection system tile and instrumentation package to monitor heating effects from boundary layer transition during re-entry. On STS-119, the windward airflow on the port wing was deliberately disrupted by a four-inch wide and quarter-inch tall protuberance built into the modified tile. In coordination with this flight experiment, a US Navy NP-3D Orion aircraft was flown 28 nautical miles below Discovery and remotely monitored surface temperature of the Orbiter at Mach 8.4 using a long-range infrared optical package referred to as Cast Glance. Approximately two months later, the same Navy Cast Glance aircraft successfully monitored the surface temperatures of the Orbiter Atlantis traveling at approximately Mach 14.3 during its return from the successful Hubble repair mission. In contrast to Discovery, Atlantis was not part of the Boundary Layer Transition (BLT) flight experiment, thus the vehicle was not configured with a protuberance on the port wing. In September 2009, Cast Glance was again successful in capturing infrared imagery and monitoring the surface temperatures on Discovery s next flight, STS-128. Again, NASA flew a specially modified thermal protection system tile and instrumentation package to monitor heating effects from boundary layer transition during re-entry. During this mission, Cast Glance was able to image laminar and turbulent flow phenomenology optimizing data collection for Mach 14.7. The purpose of this paper is to describe key elements associated with STS-119/125/128 mission planning and execution from the perspective of the Cast Glance flight crew that obtained the imagery. The paper will emphasize a human element of experience, expertise and adaptability seamlessly coupled with Cast Glance system and sensor technology required to manually collect the required imagery. Specific topics will include a near infrared (NIR) camera upgrade that was implemented just prior to the missions, how pre-flight radiance modeling was utilized to optimize the IR sensor configuration, communications, the development of aircraft test support positions based upon Shuttle trajectory information, support to contingencies such as Shuttle one orbit wave-offs/west coast diversions and then the Cast Glance perspective during an actual Shuttle imaging mission.

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

The purpose of this document is to provide the technical requirements for operation, inspection and maintenance of a TRUPACT-II Shipping Package and directly related components. This document shall supply the minimum requirements as specified in the TRUPACT-II Safety Analysis Report for Packaging (SARP) and Certificate of Compliance (C of C) 9218. In the event there is a conflict between this document and the TRUPACT-II SARP (NRC Certificate of Compliance No. 9218), the TRUPACT-II SARP shall govern. This document details the operations, maintenance, repair, replacement of components, as well as the documentation required and the procedures to be followed to maintainmore » the integrity of the TRUPACT-II container. These procedures may be modified for site use, but as a minimum all parameters and format listed herein must be included in any site modified version. For convenience and where applicable steps may be performed out of sequence. Packaging and payload handling equipment and transport trailers have been specifically designed for use with the TRUPACT-II Packaging. This document discusses the minimum required procedures for use of the adjustable center of gravity lift fixture and the TRUPACT-II transport trailer in conjunction with the TRUPACT-II Packaging.« less

Simulation of the Aerosol-Atmosphere Interaction in the Dead Sea Area with COSMO-ART

NASA Astrophysics Data System (ADS)

Vogel, Bernhard; Bangert, Max; Kottmeier, Christoph; Rieger, Daniel; Schad, Tobias; Vogel, Heike

2014-05-01

The Dead Sea is a unique environment located in the Dead Sea Rift Valley. The fault system of the Dead Sea Rift Valley marks the political borders between Israel, Jordan, and Palestine. The Dead Sea region and the ambient Eastern Mediterranean coastal zone provide a natural laboratory for studying atmospheric processes ranging from the smallest scale of cloud processes to regional weather and climate. The virtual institute DESERVE is designed as a cross-disciplinary and cooperative international project of the Helmholtz Centers KIT, GFZ, and UFZ with well-established partners in Israel, Jordan and Palestine. One main focus of one of the work packages is the role of aerosols in modifying clouds and precipitation and in developing the Dead Sea haze layer as one of the most intriguing questions. The haze influences visibility, solar radiation, and evaporation and may even affect economy and health. We applied the online coupled model system COSMO-ART, which is able to treat the feedback processes between aerosol, radiation, and cloud formation, for a case study above the Dead Sea and adjacent regions. Natural aerosol like mineral dust and sea salt as well as anthropogenic primary and secondary aerosol is taken into account. Some of the observed features like the vertical double structure of the haze layer are already covered by the simulation. We found that absorbing aerosol like mineral dust causes a temperature increase in parts of the model domain. In other areas a decrease in temperature due to cirrus clouds modified by elevated dust layers is simulated.

Atmospheric pressure gas chromatography coupled to quadrupole-time of flight mass spectrometry as a powerful tool for identification of non intentionally added substances in acrylic adhesives used in food packaging materials.

PubMed

Canellas, E; Vera, P; Domeño, C; Alfaro, P; Nerín, C

2012-04-27

Acrylic adhesives are used to manufacture multilayer laminates that are used in food packaging to form the geometric shape of the package as well as to stick labels on the packages. Once applied on the packaging adhesives can supply potential migrants that could endanger the packaged food. Adhesives are complex matrices where intentionally and non intentionally added substances are present, but the identification of the migrants is required by law. In this study atmospheric pressure gas chromatography coupled to a quadrupole hyphenated to a time of flight mass spectrometer (APGC-MS/Q-TOF) has been explored for identification of unknowns coming from three different acrylic adhesives. The results are compared to those obtained by conventional GC-MS-Q (quadrupole). Sixteen compounds were identified by GC-MS/Q and five of them were confirmed by APGC-MS/Q-TOF as their molecular ions were found. Moreover, additional three new compounds were identified and their structure was elucidated working with the spectra obtained by APGC-MS/Q-TOF. This finding was very relevant as these compounds were biocides suspected to be allergenic and cytotoxic in humans. Migration studies were carried out using Tenax as solid food simulant and the results showed that the three acrylic adhesives tested in this work were safe for being used in food packaging materials since the migration of compounds previously identified was below the limit established in the current legislation. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of packaging during storage time on retail display shelf life of longissimus muscle from two different beef production systems.

PubMed

Luzardo, S; Woerner, D R; Geornaras, I; Engle, T E; Delmore, R J; Hess, A M; Belk, K E

2016-06-01

Two studies were conducted to evaluate the influence of packaging and production system (PS) on retail display life color (L*, a*, and b*), fatty acid profile (% of total fatty acids), lipid oxidation (thiobarbituric acid reactive substances; mg malondialdehyde/kg of muscle), vitamin E content (µg/g of muscle), and odor (trained panelists) during storage of LM. Four (or 3) different packaging treatments were applied to LM from steers fattened on grazing systems (Uruguayan) or on high-concentrate diets (U.S.). From fabrication to application of treatments, Uruguayan LM were vacuum packaged for air shipment and U.S. LM were also vacuum packaged and kept in a cooler until Uruguayan samples arrived. Treatments were applied 7 d after slaughter. In Exp. 1, treatments were vacuum packaging (VP), low-oxygen (O) modified atmosphere packaging (MAP) with nitrogen (N2) and carbon dioxide (MAP/CO), low-O MAP with N2 plus CO and carbon monoxide (MAP/CO), and VP plus an application of peroxyacetic acid (VP/PAA). In Exp. 2 block 1, treatments were VP, MAP/CO, and VP with ethyl-arginate HCl incorporated into the film as an antimicrobial agent (VP/AM). In Exp. 2 block 2, treatments were VP, MAP/CO, MAP/CO, and VP/AM. After 35 d storage, steaks were evaluated during simulated retail display for up to 6 d. In Exp. 1, Uruguayan steaks under MAP/CO had greater ( < 0.05) a* values than VP/PAA and MAP/CO on d 6 of display. For U.S. beef, the MAP/CO had the reddest lean color ( < 0.05) compared with the other 3 packaging treatments on d 6 of display in Exp. 1. Packaging × PS × time interaction was significant ( < 0.05) in Exp. 1. In Exp. 2, MAP/CO in Uruguayan steaks also had the greatest a* values on d 6 of display, but no differences ( > 0.05) were detected among both VP and MAP/CO in U.S. steaks at this time. No significant ( > 0.05) packaging × PS × time interaction was observed in Exp. 2. Only PS (both experiments) and time (Exp. 1) affected ( < 0.05) L* values. In both experiments, U.S. steaks had greater ( < 0.05) L* values than Uruguayan steaks. Vitamin E content in Uruguayan steaks was greater ( < 0.05) than in U.S. steaks. Packaging × PS, PS × time, and packaging × PS × time interactions were not significant ( > 0.05) for any of the fatty acids. Beef from Uruguayan had lower ( < 0.05) SFA and MUFA and greater ( < 0.05) PUFA and n-6 and n-3 fatty acid percentages than U.S. beef. Complexity of fresh meat postmortem chemistry warrants a more comprehensive approach to maximize shelf life.

Cow biological type affects ground beef colour stability.

PubMed

Raines, Christopher R; Hunt, Melvin C; Unruh, John A

2009-12-01

To determine the effects of cow biological type on colour stability of ground beef, M. semimembranosus from beef-type (BSM) and dairy-type (DSM) cows was obtained 5d postmortem. Three blends (100% BSM, 50% BSM+50% DSM, 100% DSM) were adjusted to 90% and 80% lean points using either young beef trim (YBT) or beef cow trim (BCT), then packaged in high oxygen (High-O(2); 80% O(2)) modified atmosphere (MAP). The BSM+YBT patties had the brightest colour initially, but discoloured rapidly. Although DSM+BCT patties had the darkest colour initially, they discoloured least during display. Metmyoglobin reducing ability of ground DSM was up to fivefold greater than ground BSM, and TBARS values of BSM was twofold greater than DSM by the end of display (4d). Though initially darker than beef cow lean, dairy cow lean has a longer display colour life and may be advantageous to retailers using High-O(2) MAP.

21 CFR 177.1640 - Polystyrene and rubber-modified polystyrene.

Code of Federal Regulations, 2011 CFR

2011-04-01

... polystyrene and rubber-modified polystyrene used in food-packaging adhesives complying with § 175.105 of this... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Polystyrene and rubber-modified polystyrene. 177.1640 Section 177.1640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

21 CFR 177.1640 - Polystyrene and rubber-modified polystyrene.

Code of Federal Regulations, 2010 CFR

2010-04-01

... polystyrene and rubber-modified polystyrene used in food-packaging adhesives complying with § 175.105 of this... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Polystyrene and rubber-modified polystyrene. 177.1640 Section 177.1640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

21 CFR 177.1640 - Polystyrene and rubber-modified polystyrene.

Code of Federal Regulations, 2013 CFR

2013-04-01

... polystyrene and rubber-modified polystyrene used in food-packaging adhesives complying with § 175.105 of this... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Polystyrene and rubber-modified polystyrene. 177.1640 Section 177.1640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

21 CFR 177.1640 - Polystyrene and rubber-modified polystyrene.

Code of Federal Regulations, 2012 CFR

2012-04-01

... polystyrene and rubber-modified polystyrene used in food-packaging adhesives complying with § 175.105 of this... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Polystyrene and rubber-modified polystyrene. 177.1640 Section 177.1640 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

An atmospheric dispersion index for prescribed burning

Treesearch

Leonidas G. Lavdas

1986-01-01

A numerical index that estimates the atmosphere's capacity to disperse smoke from prescribed burning is described. The physical assumptions and mathematical development of the index are given in detail. A preliminary interpretation of dispersion index values is offered. A FORTRAN subroutine package for computing the index is included.

Efficient Transduction of Human and Rhesus Macaque Primary T Cells by a Modified Human Immunodeficiency Virus Type 1-Based Lentiviral Vector.

PubMed

He, Huan; Xue, Jing; Wang, Weiming; Liu, Lihong; Ye, Chaobaihui; Cong, Zhe; Kimata, Jason T; Qin, Chuan; Zhou, Paul

2017-03-01

Human immunodeficiency virus type 1 (HIV-1)-based lentiviral vectors efficiently transduce genes to human, but not rhesus, primary T cells and hematopoietic stem cells (HSCs). The poor transduction of HIV-1 vectors to rhesus cells is mainly due to species-specific restriction factors such as rhesus TRIM5α. Previously, several strategies to modify HIV-1 vectors were developed to overcome rhesus TRIM5α restriction. While the modified HIV-1 vectors efficiently transduce rhesus HSCs, they remain suboptimal for rhesus primary T cells. Recently, HIV-1 variants that encode combinations of LNEIE mutations in capsid (CA) protein and SIVmac239 Vif were found to replicate efficiently in rhesus primary T cells. Thus, the present study tested whether HIV-1 vectors packaged by a packaging construct containing these CA substitutions could efficiently transduce both human and rhesus primary CD4 T cells. To accomplish this, LNEIE mutations were made in the packaging construct CEMΔ8.9, and recombinant HIV-1 vectors packaged by Δ8.9 WT or Δ8.9 LNEIE were generated. Transduction rates, CA stability, and vector integration in CEMss-CCR5 and CEMss-CCR5-rhTRIM5α/green fluorescent protein cells, as well as transduction rates in human and rhesus primary CD4 T cells by Δ8.9 WT or Δ8.9 LNEIE-packaged HIV-1 vectors, were compared. Finally, the influence of rhesus TRIM5α variations in transduction rates to primary CD4 T cells from a cohort of 37 Chinese rhesus macaques was studied. While it maintains efficient transduction for human T-cell line and primary CD4 T cells, Δ8.9 LNEIE-packaged HIV-1 vector overcomes rhesus TRIM5α-mediated CA degradation, resulting in significantly higher transduction efficiency of rhesus primary CD4 T cells than Δ8.9 WT-packaged HIV-1 vector. Rhesus TRIM5α variations strongly influence transduction efficiency of rhesus primary CD4 T cells by both Δ8.9 WT or Δ8.9 LNEIE-packaged HIV-1 vectors. Thus, it is concluded that Δ8.9 LNEIE-packaged HIV-1 vector overcomes rhesus TRIM5α restriction and efficiently transduces both human and rhesus primary T cells.

Efficient Transduction of Human and Rhesus Macaque Primary T Cells by a Modified Human Immunodeficiency Virus Type 1–Based Lentiviral Vector

PubMed Central

He, Huan; Xue, Jing; Wang, Weiming; Liu, Lihong; Ye, Chaobaihui; Cong, Zhe; Kimata, Jason T.; Qin, Chuan; Zhou, Paul

2017-01-01

Human immunodeficiency virus type 1 (HIV-1)-based lentiviral vectors efficiently transduce genes to human, but not rhesus, primary T cells and hematopoietic stem cells (HSCs). The poor transduction of HIV-1 vectors to rhesus cells is mainly due to species-specific restriction factors such as rhesus TRIM5α. Previously, several strategies to modify HIV-1 vectors were developed to overcome rhesus TRIM5α restriction. While the modified HIV-1 vectors efficiently transduce rhesus HSCs, they remain suboptimal for rhesus primary T cells. Recently, HIV-1 variants that encode combinations of LNEIE mutations in capsid (CA) protein and SIVmac239 Vif were found to replicate efficiently in rhesus primary T cells. Thus, the present study tested whether HIV-1 vectors packaged by a packaging construct containing these CA substitutions could efficiently transduce both human and rhesus primary CD4 T cells. To accomplish this, LNEIE mutations were made in the packaging construct CEMΔ8.9, and recombinant HIV-1 vectors packaged by Δ8.9 WT or Δ8.9 LNEIE were generated. Transduction rates, CA stability, and vector integration in CEMss-CCR5 and CEMss-CCR5-rhTRIM5α/green fluorescent protein cells, as well as transduction rates in human and rhesus primary CD4 T cells by Δ8.9 WT or Δ8.9 LNEIE-packaged HIV-1 vectors, were compared. Finally, the influence of rhesus TRIM5α variations in transduction rates to primary CD4 T cells from a cohort of 37 Chinese rhesus macaques was studied. While it maintains efficient transduction for human T-cell line and primary CD4 T cells, Δ8.9 LNEIE-packaged HIV-1 vector overcomes rhesus TRIM5α-mediated CA degradation, resulting in significantly higher transduction efficiency of rhesus primary CD4 T cells than Δ8.9 WT-packaged HIV-1 vector. Rhesus TRIM5α variations strongly influence transduction efficiency of rhesus primary CD4 T cells by both Δ8.9 WT or Δ8.9 LNEIE-packaged HIV-1 vectors. Thus, it is concluded that Δ8.9 LNEIE-packaged HIV-1 vector overcomes rhesus TRIM5α restriction and efficiently transduces both human and rhesus primary T cells. PMID:28042947

Influence of Modified Atmosphere Storage on Aflatoxin Production in High Moisture Corn

PubMed Central

Wilson, David M.; Jay, Edward

1975-01-01

Samples of freshly harvested corn and remoistened corn were inoculated with Aspergillus flavus and stored for 4 weeks at about 27 C in air and three modified atmospheres. Aflatoxins and fat acidity were determined weekly. Corn stored in the modified atmospheres did not accumulate over 15 μg of aflatoxin B1 per kg and 20 μg of total aflatoxins per kg. Corn from the high CO2 treatment (61.7% CO2, 8.7% O2, and 29.6% N2) was visibly molded at 4 weeks and had a higher fat acidity than the other treatments. In the N2 (99.7% N2 and 0.3% O2) and controlled atmosphere (13.5% CO2, 0.5% O2, 84.8% N2) treatments, a fermentation-like odor was detected. When the corn was removed from the modified atmospheres it deteriorated rapidly and was soon contaminated with aflatoxins. PMID:803817

Mars Observer: Phase 0 safety review data package

NASA Technical Reports Server (NTRS)

1986-01-01

The Mars Observer Program has as its primary objectives a study of the geochemistry, atmospheric dynamics, atmosphere/surface interactions, seasonal variations, and magnetic field characteristics of Mars. The Mars Observer Spacecraft, safety critical spacecraft subsystems, ground support equipment, ground operations scenario, requirements matrix, and equipment specifications are described.

SUBOPT: A CAD program for suboptimal linear regulators

NASA Technical Reports Server (NTRS)

Fleming, P. J.

1985-01-01

An interactive software package which provides design solutions for both standard linear quadratic regulator (LQR) and suboptimal linear regulator problems is described. Intended for time-invariant continuous systems, the package is easily modified to include sampled-data systems. LQR designs are obtained by established techniques while the large class of suboptimal problems containing controller and/or performance index options is solved using a robust gradient minimization technique. Numerical examples demonstrate features of the package and recent developments are described.

Stellar atmosphere modeling of extremely hot, compact stars

NASA Astrophysics Data System (ADS)

Rauch, Thomas; Ringat, Ellen; Werner, Klaus

Present X-ray missions like Chandra and XMM-Newton provide excellent spectra of extremely hot white dwarfs, e.g. burst spectra of novae. Their analysis requires adequate NLTE model atmospheres. The Tuebingen Non-LTE Model-Atmosphere Package (TMAP) can calculate such model at-mospheres and spectral energy distributions at a high level of sophistication. We present a new grid of models that is calculated in the parameter range of novae and supersoft X-ray sources and show examples of their application.

Effect of gamma irradiation under various atmospheres of packaging on the microbial and physicochemical properties of turmeric powder

NASA Astrophysics Data System (ADS)

Esmaeili, Saeideh; Barzegar, Mohsen; Sahari, Mohammad Ali; Berengi-Ardestani, Samira

2018-07-01

This study investigated the effect of gamma irradiation (0, 5, 10, and 15 kGy) under various atmospheres of packaging (air, N₂, and vacuum) on the microbial load and physicochemical properties of turmeric powder, including antioxidant activities, total phenolic content (TPC), color parameters, and curcuminoid content. The efficiency of irradiation in reducing microbial contamination in the samples was observed even at the lowest dose. By increasing the irradiation dose, the microbial load was not detectable. Irradiation in the presence of oxygen had synergistic effects on the extraction of curcuminoids and TPC, and increased the antioxidant activity of the methanolic extracts: highest activity was observed at 15 kGy. Generally, gamma irradiation up to the dose of 10 kGy under air atmosphere not only ensured microbial safety and desirability of turmeric powder, but also improved the extraction yield of bioactive compounds and, consequently, antioxidant activities of the samples.

VMSbase: an R-package for VMS and logbook data management and analysis in fisheries ecology.

PubMed

Russo, Tommaso; D'Andrea, Lorenzo; Parisi, Antonio; Cataudella, Stefano

2014-01-01

VMSbase is an R package devised to manage, process and visualize information about fishing vessels activity (provided by the vessel monitoring system--VMS) and catches/landings (as reported in the logbooks). VMSbase is primarily conceived to be user-friendly; to this end, a suite of state-of-the-art analyses is accessible via a graphical interface. In addition, the package uses a database platform allowing large datasets to be stored, managed and processed vey efficiently. Methodologies include data cleaning, that is removal of redundant or evidently erroneous records, and data enhancing, that is interpolation and merging with external data sources. In particular, VMSbase is able to estimate sea bottom depth for single VMS pings using an on-line connection to the National Oceanic and Atmospheric Administration (NOAA) database. It also allows VMS pings to be assigned to whatever geographic partitioning has been selected by users. Standard analyses comprise: 1) métier identification (using a modified CLARA clustering approach on Logbook data or Artificial Neural Networks on VMS data); 2) linkage between VMS and Logbook records, with the former organized into fishing trips; 3) discrimination between steaming and fishing points; 4) computation of spatial effort with respect to user-selected grids; 5) calculation of standard fishing effort indicators within Data Collection Framework; 6) a variety of mapping tools, including an interface for Google viewer; 7) estimation of trawled area. Here we report a sample workflow for the accessory sample datasets (available with the package) in order to explore the potentialities of VMSbase. In addition, the results of some performance tests on two large datasets (1×10(5) and 1×10(6) VMS signals, respectively) are reported to inform about the time required for the analyses. The results, although merely illustrative, indicate that VMSbase can represent a step forward in extracting and enhancing information from VMS/logbook data for fisheries studies.

Bibliographic Networks and Microcomputer Applications for Aerospace and Defense Scientific and Technical Information.

DTIC Science & Technology

1986-10-01

The package had been modified and enhanced by a commercial vendor who was marketing the package. Unforeseen events halted pursuit of this approach and...them against the criteria listed in the test plan. Benchmarking took over 10 months to complete. The UNICORN System from SIRSI Corporation and BRS

Black pepper powder microbiological quality improvement using DBD systems in atmospheric pressure

NASA Astrophysics Data System (ADS)

Grabowski, Maciej; Hołub, Marcin; Balcerak, Michał; Kalisiak, Stanisław; Dąbrowski, Waldemar

2015-07-01

Preliminary results are given regarding black pepper powder decontamination using dielectric barrier discharge (DBD) plasma in atmospheric pressure. Three different DBD reactor constructions were investigated, both packaged and unpackaged material was treated. Due to potential, industrial applications, in addition to microbiological results, water activity, loss of mass and the properties of packaging material, regarding barrier properties were investigated. Argon based treatment of packed pepper with DBD reactor configuration is proposed and satisfactory results are presented for treatment time of 5 min or less. Contribution to the topical issue "The 14th International Symposium on High Pressure Low Temperature Plasma Chemistry (HAKONE XIV)", edited by Nicolas Gherardi, Ronny Brandenburg and Lars Stollenwark

Altitude release mechanism

DOEpatents

Kulhanek, Frank C.

1977-01-01

An altitude release mechanism for releasing a radiosonde or other measuring instrument from a balloon carrying it up into the atmosphere includes a bottle partially filled with water, a tube sealed into the bottle having one end submerged in the water in the bottle and the free end extending above the top of the bottle and a strip of water-disintegrable paper held within the free end of the tube linking the balloon to the remainder of the package. As the balloon ascends, the lowered atmospheric air pressure causes the air in the bottle to expand, forcing the water in the bottle up the tubing to wet and disintegrate the paper, releasing the package from the balloon.

Studies of the earth-limb absorptions in the near ultraviolet. [atmospheric chemistry

NASA Technical Reports Server (NTRS)

Murcray, D. G.

1980-01-01

The use of solar occultation techniques as a means of obtaining data on the photochemistry of the ozone layer was investigated. A spectrometer equipped with a photomultiplier detector and associated electronics necessary to amplify the output of the detector up to a level suitable for on-board recording and also for telemetering to the ground, was packaged with a solar telescope and flown by balloon in order to obtain solar spectra in the region between 3080 A and 3100 A with a resolution of close to 0.05 A. Data reduction techniques required to remove solar OH lines from atmospheric OH line spectra are described as well as the instrument package.

Effect of packaging during storage time on retail display microbial population of beef strip loins from two different production systems.

PubMed

Luzardo, S; Woerner, D R; Geornaras, I; Hess, A M; Belk, K E

2016-06-01

Two studies were conducted to evaluate the influence of packaging during storage of strip loins (to simulate export shipment) from steers fattened on intensive grazing systems (Uruguay; UR) or on a high-concentrate diet (United States; US) on retail display life microbial growth. Four or 3 different packaging treatments were applied to UR and US strip loin roasts or steaks during 35 d of storage; treatments were applied 7 d following slaughter. After 35 d of storage, the samples were evaluated during simulated retail display for up to 6 d. In Exp. 1, the treatments were vacuum packaging (VP), low-oxygen modified atmosphere packaging (MAP) with N and CO (MAP/CO), low-oxygen MAP with N plus CO and CO, and VP plus an application of peroxyacetic acid (VP/PAA). In Exp. 2, block 1, the treatments were VP, MAP/CO, and VP with ethyl--lauroyl--arginate HCl incorporated into the film as an antimicrobial agent (VP/AM). In Exp. 2, block 2, the treatments were VP, MAP/CO, MAP/CO, and VP/AM. For retail display, VP treatments were sliced and repackaged in PVC overwrap, and MAP treatments were actually PVC overwrap trays that were removed from a master bag with the prescribed gas treatment. Regardless of production system and packaging treatment, mesophilic and psychrotrophic counts of 6.9 to 7.8 and 6.7 to 7.7 log10 CFU/cm, respectively, were obtained at the end of retail display, except for US samples in Exp. 2 (5.5 to 6.3 log CFU/cm). No differences ( > 0.05) were detected for spp. counts among packaging treatments in US steaks at the end of the display time in Exp.1, whereas, for UR steaks, both MAP treatments had lower ( < 0.05) spp. counts than VP treatments. spp. counts were lower ( < 0.05) in the MAP/CO treatment than in the other 3 treatments in US samples on d 6 of retail display for Exp. 2. At the end of display time and for Exp. 1, US steaks under MAP/CO had greater ( < 0.05) lactic acid bacteria (LAB) counts than samples in both VP treatments; no differences ( > 0.05) among packaging were detected for UR steaks. Both MAP and VP/AM treatments in the US samples for Exp. 2 had lower ( < 0.05) LAB counts on d 6 of display than the VP treatment, but no differences ( > 0.05) were found among packaging treatments for the UR samples. To maximize shelf life (storage and display life) of exported fresh beef, it is critical to minimize bacterial populations during processing and storage.

Production of biogenic amines by lactic acid bacteria and enterobacteria isolated from fresh pork sausages packaged in different atmospheres and kept under refrigeration.

PubMed

Curiel, J A; Ruiz-Capillas, C; de Las Rivas, B; Carrascosa, A V; Jiménez-Colmenero, F; Muñoz, R

2011-07-01

The occurrence of in vitro amino acid activity in bacterial strains associated with fresh pork sausages packaged in different atmospheres and kept in refrigeration was studied. The presence of biogenic amines in decarboxylase broth was confirmed by ion-exchange chromatography and by the presence of the corresponding decarboxylase genes by PCR. From the 93 lactic acid bacteria and 100 enterobacteria strains analysed, the decarboxylase medium underestimates the number of biogenic amine-producer strains. 28% of the lactic acid bacteria produced tyramine and presented the tdc gene. All the tyramine-producer strains were molecularly identified as Carnobacterium divergens. Differences on the relative abundance of C. divergens were observed among the different packaging atmospheres assayed. After 28 days of storage, the presence of argon seems to inhibit C. divergens growth, while packing under vacuum seems to favour it. Among enterobacteria, putrescine was the amine more frequently produced (87%), followed by cadaverine (85%); agmatine and tyramine were only produced by 13 and 1%, respectively, of the strains analysed. Packing under vacuum or in an atmosphere containing nitrogen seems to inhibit the growth of enterobacteria which produce simultaneously putrescine, cadaverine, and agmatine. Contrarily, over-wrapping or packing in an atmosphere containing argon seems to favour the growth of agmatine producer-enterobacteria. The production of putrescine and cadaverine was associated with the presence of the corresponding amino acid decarboxylase genes. The biogenic amine-producer strains were included in a wide range of enterobacterial species, including Kluyvera intermedia, Enterobacter aerogenes, Yersinia kristensenii, Serratia grimesii, Serratia ficaria, Yersinia rodhei, Providencia vermicola and Obesumbacterium proteus. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of dark storage and retail display on beef chuck and round muscles enhanced with ammonium hydroxide, salt, and carbon monoxide.

PubMed

Hamling, A E; Jenschke, B E; Calkins, C R

2008-04-01

The objective of this study was to determine the retail shelf stability of beef chuck and round muscles enhanced with ammonium hydroxide, salt, and carbon monoxide. A split plot design was used for each of 3 muscles [triceps brachii (TB), biceps femoris (BF), and rectus femoris (RF)] with 2 treatments (0 and 20% pump), 3 dark storage periods (1, 2, and 3 wk), and 3 replications in the whole plot and retail display period as the split plot. There were a total of 12 subprimals per treatment per dark storage period (n = 72 each). Individual steaks were cut to a thickness of 2.54 cm and packaged in a modified-atmosphere package (MAP). The TB was packaged in a high-oxygen MAP (80% oxygen, 20% carbon dioxide). The BF and RF were packaged in a low-oxygen MAP (100% carbon dioxide). At the completion of each dark storage period, steaks were subjected to 7 d of simulated retail display. Steaks were used for objective and subjective color measurements, total plate counts, and determination of retail purge and oxidation. For all muscles, total plate counts were always numerically greater in injected steaks. Triceps brachii steaks held in dark storage for 3 wk and displayed at retail for 4 or more days all exceeded 10(7) log of cfu/cm(2) for aerobic plate count. Biceps femoris and RF steaks packaged in a low-oxygen MAP had much lower bacterial counts, with levels below 4.2 log of cfu/cm(2), even after 7 d of retail display. Oxidation values for the TB were extremely high (ranging from 12.3 to 26.6), whereas the BF and RF had values that were much lower (< or =1.0 mg of malonaldehyde/kg of muscle), likely due to the oxidation occurring in a high-oxygen MAP for the TB. Enhanced TB steaks proved to have greater color stability (less discoloration) than nonenhanced TB steaks. In addition, the BF and RF (low-oxygen MAP) steaks had better color stability (more stable redness values) than TB (high-oxygen MAP) steaks, although TB steaks initially exhibited a brighter red color. Retail display life was enhanced by packaging in 100% carbon dioxide, and enhanced steaks exhibited greater color stability in retail display than control steaks.

Tests of a Semi-Analytical Case 1 and Gelbstoff Case 2 SeaWiFS Algorithm with a Global Data Set

NASA Technical Reports Server (NTRS)

Carder, Kendall L.; Hawes, Steve K.; Lee, Zhongping

1997-01-01

A semi-analytical algorithm was tested with a total of 733 points of either unpackaged or packaged-pigment data, with corresponding algorithm parameters for each data type. The 'unpackaged' type consisted of data sets that were generally consistent with the Case 1 CZCS algorithm and other well calibrated data sets. The 'packaged' type consisted of data sets apparently containing somewhat more packaged pigments, requiring modification of the absorption parameters of the model consistent with the CalCOFI study area. This resulted in two equally divided data sets. A more thorough scrutiny of these and other data sets using a semianalytical model requires improved knowledge of the phytoplankton and gelbstoff of the specific environment studied. Since the semi-analytical algorithm is dependent upon 4 spectral channels including the 412 nm channel, while most other algorithms are not, a means of testing data sets for consistency was sought. A numerical filter was developed to classify data sets into the above classes. The filter uses reflectance ratios, which can be determined from space. The sensitivity of such numerical filters to measurement resulting from atmospheric correction and sensor noise errors requires further study. The semi-analytical algorithm performed superbly on each of the data sets after classification, resulting in RMS1 errors of 0.107 and 0.121, respectively, for the unpackaged and packaged data-set classes, with little bias and slopes near 1.0. In combination, the RMS1 performance was 0.114. While these numbers appear rather sterling, one must bear in mind what mis-classification does to the results. Using an average or compromise parameterization on the modified global data set yielded an RMS1 error of 0.171, while using the unpackaged parameterization on the global evaluation data set yielded an RMS1 error of 0.284. So, without classification, the algorithm performs better globally using the average parameters than it does using the unpackaged parameters. Finally, the effects of even more extreme pigment packaging must be examined in order to improve algorithm performance at high latitudes. Note, however, that the North Sea and Mississippi River plume studies contributed data to the packaged and unpackaged classess, respectively, with little effect on algorithm performance. This suggests that gelbstoff-rich Case 2 waters do not seriously degrade performance of the semi-analytical algorithm.

Column Grid Array Rework for High Reliability

NASA Technical Reports Server (NTRS)

Mehta, Atul C.; Bodie, Charles C.

2008-01-01

Due to requirements for reduced size and weight, use of grid array packages in space applications has become common place. To meet the requirement of high reliability and high number of I/Os, ceramic column grid array packages (CCGA) were selected for major electronic components used in next MARS Rover mission (specifically high density Field Programmable Gate Arrays). ABSTRACT The probability of removal and replacement of these devices on the actual flight printed wiring board assemblies is deemed to be very high because of last minute discoveries in final test which will dictate changes in the firmware. The questions and challenges presented to the manufacturing organizations engaged in the production of high reliability electronic assemblies are, Is the reliability of the PWBA adversely affected by rework (removal and replacement) of the CGA package? and How many times can we rework the same board without destroying a pad or degrading the lifetime of the assembly? To answer these questions, the most complex printed wiring board assembly used by the project was chosen to be used as the test vehicle, the PWB was modified to provide a daisy chain pattern, and a number of bare PWB s were acquired to this modified design. Non-functional 624 pin CGA packages with internal daisy chained matching the pattern on the PWB were procured. The combination of the modified PWB and the daisy chained packages enables continuity measurements of every soldered contact during subsequent testing and thermal cycling. Several test vehicles boards were assembled, reworked and then thermal cycled to assess the reliability of the solder joints and board material including pads and traces near the CGA. The details of rework process and results of thermal cycling are presented in this paper.

Effect of protective atmosphere on color of goose meat.

PubMed

Orkusz, A; Woloszyn, J; Haraf, G; Okruszek, A

2013-08-01

The objective of the work was to characterize the color of the of the goose breast meat packaged in protective atmosphere and stored in the refrigerated conditions. The aim was realized by determination of total heme pigment concentration; relative concentration of myoglobin, oxymyoglobin, and metmyoglobin; parameters of color L* (lightness), a* (redness), and b* (yellowness); and sensory evaluation of the surface color. The experimental material was White Kołuda goose boneless breast meat with the skin from industrial slaughter. The following 2 protective atmospheres were used in the study: vacuum and modified atmosphere (MA) consisting of 80% O2 and 20% CO2. The muscles packed in protective atmosphere were examined on d 4, 7, 11, and 14 of storage. A control sample was goose breast meat stored in air and tested after 24 h after slaughter. The total pigment concentration decreased gradually within 14 d of storage for samples packed in 2 types of atmospheres. The increase in relative concentration of metmyoglobin and the decrease in oxymyoglobin relative concentration in total heme pigments in the meat stored in MA was noticed. However, in all times of storage, the relative concentration of the 3 samples of myoglobin forms stored in vacuum was unchanged. The color parameters (L*, a*, b*) did not change for 14 d of storage in the muscles packed in vacuum. One can state a decrease of the value of the color parameter a* as well as an increase of the value of the color parameter b* in the samples packed in MA. From d 11 to 14 of storage, goose meat packed under MA had lower sensory evaluation intensity of color than muscles under vacuum. The obtained data indicated that the surface color of goose breast meat packed in MA (consisting of 80% O2, 20% CO2) or vacuum packed was maintained for 11 and 14 d, respectively.

Sodium lactate addition on the quality and shelf life of refrigerated sliced poultry sausage packaged in air or nitrogen atmosphere.

PubMed

Cegielska-Radziejewska, Renata; Pikul, Jan

2004-03-01

The aim of this study was to determine the effect of sodium lactate addition on shelf-life extension of sliced poultry sausage packaged both in air and nitrogen atmospheres and stored in refrigerated conditions. Basic chemical composition, pH, and malonaldehyde content were assayed and color measurement using the reflection method was carried out. Microbiological examination consisted of determination of total number of aerobic psychrotrophic bacteria and number of lactic acid bacteria. Sensory evaluation of products was performed. Microbiological and sensory quality of sliced poultry meat sausage was dependent on the addition during production of sodium lactate and the composition of gases (air or nitrogen) used in packaging. Slices of poultry sausage with 1% as well as 2% of sodium lactate maintained their initial quality of evaluated sensory attributes longer, irrespective of the applied gases. Sodium lactate inhibited growth of aerobic psychrotrophic bacteria and lactic acid bacteria during refrigerated storage. Sodium lactate also inhibited the formation of malonaldehyde in sliced poultry sausage during refrigerated storage. The effectiveness of this process depended on the concentration of sodium lactate addition. It was concluded that 1% as well as 2% addition of sodium lactate could extend the shelf life of sliced poultry sausage packaged in air atmosphere and stored at 5 to 7 degrees C by 3 or 4 times, respectively. Sliced poultry sausage treated with 2% sodium lactate packed in nitrogen had the longest (35-day) shelf life. This was a sevenfold increase in the shelf life of sliced poultry sausage compared with the control.

White Dwarf Model Atmospheres: Synthetic Spectra for Supersoft Sources

NASA Astrophysics Data System (ADS)

Rauch, Thomas

2013-01-01

The Tübingen NLTE Model-Atmosphere Package (TMAP) calculates fully metal-line blanketed white dwarf model atmospheres and spectral energy distributions (SEDs) at a high level of sophistication. Such SEDs are easily accessible via the German Astrophysical Virtual Observatory (GAVO) service TheoSSA. We discuss applications of TMAP models to (pre) white dwarfs during the hottest stages of their stellar evolution, e.g. in the parameter range of novae and supersoft sources.

Performance of a Diaphragmed Microlens for a Packaged Microspectrometer

PubMed Central

Lo, Joe; Chen, Shih-Jui; Fang, Qiyin; Papaioannou, Thanassis; Kim, Eun-Sok; Gundersen, Martin; Marcu, Laura

2009-01-01

This paper describes the design, fabrication, packaging and testing of a microlens integrated in a multi-layered MEMS microspectrometer. The microlens was fabricated using modified PDMS molding to form a suspended lens diaphragm. Gaussian beam propagation model was used to measure the focal length and quantify M2 value of the microlens. A tunable calibration source was set up to measure the response of the packaged device. Dual wavelength separation by the packaged device was demonstrated by CCD imaging and beam profiling of the spectroscopic output. We demonstrated specific techniques to measure critical parameters of microoptics systems for future optimization of spectroscopic devices. PMID:22399943

A moist aquaplanet variant of the Held–Suarez test for atmospheric model dynamical cores

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thatcher, Diana R.; Jablonowski, Christiane

A moist idealized test case (MITC) for atmospheric model dynamical cores is presented. The MITC is based on the Held–Suarez (HS) test that was developed for dry simulations on “a flat Earth” and replaces the full physical parameterization package with a Newtonian temperature relaxation and Rayleigh damping of the low-level winds. This new variant of the HS test includes moisture and thereby sheds light on the nonlinear dynamics–physics moisture feedbacks without the complexity of full-physics parameterization packages. In particular, it adds simplified moist processes to the HS forcing to model large-scale condensation, boundary-layer mixing, and the exchange of latent and sensible heat betweenmore » the atmospheric surface and an ocean-covered planet. Using a variety of dynamical cores of the National Center for Atmospheric Research (NCAR)'s Community Atmosphere Model (CAM), this paper demonstrates that the inclusion of the moist idealized physics package leads to climatic states that closely resemble aquaplanet simulations with complex physical parameterizations. This establishes that the MITC approach generates reasonable atmospheric circulations and can be used for a broad range of scientific investigations. This paper provides examples of two application areas. First, the test case reveals the characteristics of the physics–dynamics coupling technique and reproduces coupling issues seen in full-physics simulations. In particular, it is shown that sudden adjustments of the prognostic fields due to moist physics tendencies can trigger undesirable large-scale gravity waves, which can be remedied by a more gradual application of the physical forcing. Second, the moist idealized test case can be used to intercompare dynamical cores. These examples demonstrate the versatility of the MITC approach and suggestions are made for further application areas. Furthermore, the new moist variant of the HS test can be considered a test case of intermediate complexity.« less

A moist aquaplanet variant of the Held–Suarez test for atmospheric model dynamical cores

DOE PAGES

Thatcher, Diana R.; Jablonowski, Christiane

2016-04-04

A moist idealized test case (MITC) for atmospheric model dynamical cores is presented. The MITC is based on the Held–Suarez (HS) test that was developed for dry simulations on “a flat Earth” and replaces the full physical parameterization package with a Newtonian temperature relaxation and Rayleigh damping of the low-level winds. This new variant of the HS test includes moisture and thereby sheds light on the nonlinear dynamics–physics moisture feedbacks without the complexity of full-physics parameterization packages. In particular, it adds simplified moist processes to the HS forcing to model large-scale condensation, boundary-layer mixing, and the exchange of latent and sensible heat betweenmore » the atmospheric surface and an ocean-covered planet. Using a variety of dynamical cores of the National Center for Atmospheric Research (NCAR)'s Community Atmosphere Model (CAM), this paper demonstrates that the inclusion of the moist idealized physics package leads to climatic states that closely resemble aquaplanet simulations with complex physical parameterizations. This establishes that the MITC approach generates reasonable atmospheric circulations and can be used for a broad range of scientific investigations. This paper provides examples of two application areas. First, the test case reveals the characteristics of the physics–dynamics coupling technique and reproduces coupling issues seen in full-physics simulations. In particular, it is shown that sudden adjustments of the prognostic fields due to moist physics tendencies can trigger undesirable large-scale gravity waves, which can be remedied by a more gradual application of the physical forcing. Second, the moist idealized test case can be used to intercompare dynamical cores. These examples demonstrate the versatility of the MITC approach and suggestions are made for further application areas. Furthermore, the new moist variant of the HS test can be considered a test case of intermediate complexity.« less

Effect of a Classroom-Based Behavioral Intervention Package on the Improvement of Children's Sitting Posture in Japan

ERIC Educational Resources Information Center

Noda, Wataru; Tanaka-Matsumi, Junko

2009-01-01

The present study evaluates the effect of a classroom-based behavioral intervention package to improve Japanese elementary school children's sitting posture in regular classrooms (N = 68). This study uses a multiple-baseline design across two classrooms with a modified repeated reversal within each class. The article defines appropriate sitting…

Oxidation and waste-to-energy output of aluminium waste packaging during incineration: A laboratory study.

PubMed

López, Félix A; Román, Carlos Pérez; García-Díaz, Irene; Alguacil, Francisco J

2015-09-01

This work reports the oxidation behaviour and waste-to-energy output of different semi-rigid and flexible aluminium packagings when incinerated at 850°C in an air atmosphere enriched with 6% oxygen, in the laboratory setting. The physical properties of the different packagings were determined, including their metallic aluminium contents. The ash contents of their combustion products were determined according to standard BS ISO 1171:2010. The net calorific value, the required energy, and the calorific gain associated with each packaging type were determined following standard BS EN 13431:2004. Packagings with an aluminium lamina thickness of >50μm did not fully oxidise. During incineration, the weight-for-weight waste-to-energy output of the packagings with thick aluminium lamina was lower than that of packagings with thin lamina. The calorific gain depended on the degree of oxidation of the metallic aluminium, but was greater than zero for all the packagings studied. Waste aluminium may therefore be said to act as an energy source in municipal solid waste incineration systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

The efficacy of preservation methods to inactivate foodborne viruses.

PubMed

Baert, L; Debevere, J; Uyttendaele, M

2009-05-31

During the last decade an increased incidence of infections and outbreaks attributed to foodborne viruses, in particular noroviruses (NoV), was observed world wide. The awareness of the presence of viruses on food emphasized the need to acquire knowledge regarding the effect of preservation methods upon viruses. Most foodborne viruses cannot be cultured in the laboratory, which hinders studies of their stability in food. Cultivable surrogate viruses, genetically related to the human infecting strains, are taken as a substitute to define inactivation rates. The last years, the number of survival and inactivation studies using various surrogate viruses increased. In this review, state-of-the-art information regarding the efficacy of preservation methods to reduce the level of viruses on food is compiled. In the first place, the effect of preservation methods establishing microbial growth inhibition (chilling, freezing, acidification, reduced water activity and modified atmosphere packaging) upon foodborne viruses is described. Secondly, the use of preservation methods establishing microbial inactivation such as heat treatment, high hydrostatic pressure processing and irradiation to eliminate viruses is discussed. In the third place, the efficacy of decontamination methods on fresh produce and purification procedures applied on live bivalve shellfish to reduce the viral load is included. These studies indicate that viruses persist well on chilled, acidified, frozen foods and foods packed under modified atmosphere or in dried conditions. Intervention strategies inducing microbial inactivation are required to achieve a 3 log reduction of the level of viruses. Decontamination of fresh produce reduces viruses with a maximum of 1 to 2 log while purification of live bivalves is not adequate to prevent viral outbreaks. It was noted that the effect of a particular food preservation method is dependent upon the virus tested and type of food.

Effect of time, temperature, and slicing on respiration rate of mushrooms.

PubMed

Iqbal, T; Rodrigues, F A S; Mahajan, P V; Kerry, J P

2009-08-01

Respiration rate measurement considering the effects of cutting, temperature, and storage time are important for the shelf life study and modified atmosphere-packaging design of fresh-cut produce. This study investigates in the respiration rate of fresh whole and sliced mushrooms at 0, 4, 8, 12, 16, and 20 degrees C under ambient atmosphere and different storage times. The O(2) consumption rate increased with temperature and ranged from 22.13 to 102.41 mL/(kg.h) and 28.87 to 143.22 mL/(kg.h) for whole and sliced mushrooms, respectively, in the temperature range tested. Similar trend was observed for CO(2) production rate. Slicing of mushrooms increased the respiration rate by 30% at 0 degrees C and 40% at 20 degrees C indicating that the mushrooms are not as sensitive to the stress caused by cutting as other fresh produce. Storage time affected both respiration rate of whole and sliced mushrooms and this effect was prominent at higher temperatures. The respiration rates increased initially for some time, then decreased and reached steady state value at 12, 16, and 20 degrees C. A 2nd-order polynomial equation was used to fit the respiration rate data as a function of time at each temperature tested.

The solar optical telescope

NASA Technical Reports Server (NTRS)

1990-01-01

Objectives of the Solar Optical Telescope are to study the physics of the Sun on the scale at which many of the important physical processes occur and to attain a resolution of 73km on the Sun or 0.1 arc seconds of angular resolution. Topics discussed in this overview of the Solar Optical Telescope include: why is the Solar Optical Telescope needed; current picture of the Sun's atmosphere and convection zone; scientific problems for the Solar Optical Telescope; a description of the telescope; the facility - science management, contamination control, and accessibility to the instruments; the scientific instruments - a coordinated instrument package for unlocking the Sun's secrets; parameters of the coordinated instrument package; science operations from the Space Shuttle; and the dynamic solar atmosphere.

Microbiological changes, shelf life and identification of initial and spoilage microbiota of sea bream fillets stored under various conditions using 16S rRNA gene analysis.

PubMed

Parlapani, Foteini F; Kormas, Konstantinos Ar; Boziaris, Ioannis S

2015-09-01

Sea bream fillets are one of the most important value-added products of the seafood market. Fresh seafood spoils mainly owing to bacterial action. In this study an exploration of initial and spoilage microbiota of sea bream fillets stored under air and commercial modified atmosphere packaging (MAP) at 0 and 5 °C was conducted by 16S rRNA gene sequence analysis of isolates grown on plates. Sensory evaluation and enumeration of total viable counts and spoilage microorganisms were also conducted to determine shelf life and bacterial growth respectively. Different temperatures and atmospheres affected growth and synthesis of spoilage microbiota as well as shelf life. Shelf life under air at 0 and 5 °C was 14 and 5 days respectively, while under MAP it was 20 and 8 days respectively. Initial microbiota were dominated by Pseudomonas fluorescens, Psychrobacter and Macrococcus caseolyticus. Different temperatures and atmospheres affected the synthesis of spoilage microbiota. At the end of shelf life, different phylotypes of Pseudomonas closely related to Pseudomonas fragi were found to dominate in most cases, while Pseudomonas veronii dominated in fillets under MAP at 0 °C. Furthermore, in fillets under MAP at 5 °C, new dominant species such as Carnobacterium maltaromaticum, Carnobacterium divergens and Vagococcus fluvialis were revealed. Different temperature and atmospheric conditions affected bacterial growth, shelf life and the synthesis of spoilage microbiota. Molecular identification revealed species and strains of microorganisms that have not been reported before for sea bream fillets stored under various conditions, thus providing valuable information regarding microbiological spoilage. © 2014 Society of Chemical Industry.

Legislative priorities for transportation safety in Virginia : a pilot application of a modified delphi technique : final report.

DOT National Transportation Integrated Search

1985-01-01

Using a modified version of the Delphi technique, a panel of transportation safety experts developed the following list of legislative priorities for submission to the Department of Motor Vehicles (DMV) Legislative Package for the 1986 session of the...

Inactivation of possible microorganism food contaminants on packaging foils using nonthermal plasma and hydrogen peroxide

NASA Astrophysics Data System (ADS)

Scholtz, V.; Khun, J.; Soušková, H.; Čeřovský, M.

2015-07-01

The inactivation effect of nonthermal plasma generated in electric discharge burning in air atmosphere with water or hydrogen peroxide aerosol for the application to the microbial decontamination of packaging foils is studied. The microbial inactivation is studied on two bacterial, two yeasts, and two filamentous micromycete species. The inactivation of all contaminating microorganisms becomes on the area of full 8.5 cm in diameter circular sample after short times of several tens of seconds. Described apparatus may present a possible alternative method of microbial decontamination of food packaging material or other thermolabile materials.

Inactivation of possible microorganism food contaminants on packaging foils using nonthermal plasma and hydrogen peroxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scholtz, V., E-mail: Vladimir.Scholtz@vscht.cz; Khun, J.; Soušková, H.

The inactivation effect of nonthermal plasma generated in electric discharge burning in air atmosphere with water or hydrogen peroxide aerosol for the application to the microbial decontamination of packaging foils is studied. The microbial inactivation is studied on two bacterial, two yeasts, and two filamentous micromycete species. The inactivation of all contaminating microorganisms becomes on the area of full 8.5 cm in diameter circular sample after short times of several tens of seconds. Described apparatus may present a possible alternative method of microbial decontamination of food packaging material or other thermolabile materials.

Environmental databases and other computerized information tools

NASA Technical Reports Server (NTRS)

Clark-Ingram, Marceia

1995-01-01

Increasing environmental legislation has brought about the development of many new environmental databases and software application packages to aid in the quest for environmental compliance. These databases and software packages are useful tools and applicable to a wide range of environmental areas from atmospheric modeling to materials replacement technology. The great abundance of such products and services can be very overwhelming when trying to identify the tools which best meet specific needs. This paper will discuss the types of environmental databases and software packages available. This discussion will also encompass the affected environmental areas of concern, product capabilities, and hardware requirements for product utilization.

Science: Our Solar System, From Atmosphere to Space. Authorized Course of Instruction for the Quinmester Program.

ERIC Educational Resources Information Center

Dade County Public Schools, Miami, FL.

Performance objectives are stated for both of the secondary school units included in this package of instructional guides prepared for the Dade County Florida Quinmester Program. Both units are concerned with astronomy and space: "Our Solar System" and "From Atmosphere to Space." The former deals mainly with astronomy while the…

Programmer's reference manual for the VAX-Gerber link software package. Revision 1. 0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Isobe, G.W.

1985-10-01

This guide provides the information necessary to edit, modify, and run the VAX-Gerber software link. Since the project is in the testing stage and still being modified, this guide discussess the final desired stage along with the current stage. The current stage is to set up as to allow the programmer to easily modify and update codes as necessary.

''Do-it-yourself'' software program calculates boiler efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1984-03-01

An easy-to-use software package is described which runs on the IBM Personal Computer. The package calculates boiler efficiency, an important parameter of operating costs and equipment wellbeing. The program stores inputs and calculated results for 20 sets of boiler operating data, called cases. Cases can be displayed and modified on the CRT screen through multiple display pages or copied to a printer. All intermediate calculations are performed by this package. They include: steam enthalpy; water enthalpy; air humidity; gas, oil, coal, and wood heat capacity; and radiation losses.

Airborne Atmospheric Aerosol Measurement System

NASA Astrophysics Data System (ADS)

Ahn, K.; Park, Y.; Eun, H.; Lee, H.

2015-12-01

It is important to understand the atmospheric aerosols compositions and size distributions since they greatly affect the environment and human health. Particles in the convection layer have been a great concern in global climate changes. To understand these characteristics satellite, aircraft, and radio sonde measurement methods have usually been used. An aircraft aerosol sampling using a filter and/or impactor was the method commonly used (Jay, 2003). However, the flight speed particle sampling had some technical limitations (Hermann, 2001). Moreover, the flight legal limit, altitude, prohibited airspace, flight time, and cost was another demerit. To overcome some of these restrictions, Tethered Balloon Package System (T.B.P.S.) and Recoverable Sonde System(R.S.S.) were developed with a very light optical particle counter (OPC), impactor, and condensation particle counter (CPC). Not only does it collect and measure atmospheric aerosols depending on altitudes, but it also monitors the atmospheric conditions, temperature, humidity, wind velocity, pressure, GPS data, during the measurement (Eun, 2013). In this research, atmospheric aerosol measurement using T.B.P.S. in Ansan area is performed and the measurement results will be presented. The system can also be mounted to an unmanned aerial vehicle (UAV) and create an aerial particle concentration map. Finally, we will present measurement data using Tethered Balloon Package System (T.B.P.S.) and R.S.S (Recoverable Sonde System).

Trace Gas Quantification with Small Unmanned Aerial Systems

NASA Astrophysics Data System (ADS)

Schuyler, T. J.; Guzman, M. I.; Bailey, S.; Jacob, J.

2017-12-01

Measurements of atmospheric composition are generally performed with advanced instrumentation from ground stations using tall towers and weather balloons or with manned aircraft. Unmanned aerial systems (UAS) are a promising technology for atmospheric monitoring of trace atmospheric gases as they can bridge the gap between the regions of the atmospheric boundary layer measured by ground stations and aircraft. However, in general, the sophisticated instrumentation required for these measurements are heavy, preventing its deployment with small UAS. In order to successfully detect and quantify these gases, sensor packages aboard UAS must be lightweight, have low-power consumption, and possess limits of detection on the ppm scale or below with reasonably fast response times. Thus, a new generation of portable instrument is being developed in this work to meet these requirements employing new sensing packages. The cross sensitivity of these sensors to several gases is examined through laboratory testing of the instrument under variable environmental conditions prior to performing field measurements. Datasets include timestamps with position, temperature, relative humidity, pressure, along with variable mixing ratio values of important greenhouse gases. The work will present an analysis of the results gathered during authorized flights performed during the second CLOUD-MAP§ field campaign held in June 2017. §CLOUD-MAP: Collaboration Leading Operational UAS Development for Meteorology and Atmospheric Physics, a 4-year NSF funded effort.

Bacterial quality and safety of packaged fresh leafy vegetables at the retail level in Finland.

PubMed

Nousiainen, L-L; Joutsen, S; Lunden, J; Hänninen, M-L; Fredriksson-Ahomaa, M

2016-09-02

Consumption of packaged fresh leafy vegetables, which are convenient ready-to-eat products, has increased during the last decade. The number of foodborne outbreaks associated with these products has concurrently increased. In our study, (1) label information, (2) O2/CO2 composition, (3) bacterial quality and (4) safety of 100 fresh leafy vegetables at the retail level were studied in Finland during 2013. Bacterial quality was studied using aerobic bacteria (AB) and coliform bacteria (CB) counts, and searching for the presence of Escherichia coli, Listeria and Yersinia. The safety was studied by the presence of Salmonella, ail-positive Yersinia, stx-positive E. coli (STEC) and Listeria monocytogenes using PCR and culturing. Important label information was unavailable on several packages originating from different companies. The packaging date was missing on all packages and the date of durability on 83% of the packages. Storage temperature was declared on 62% of the packages and 73% of the packages contained information about prewashing. The batch/lot number was missing on 29% of the packages. Very low oxygen (O2) (<1%) and elevated carbon dioxide (CO2) (2-22%) concentrations were measured in all packages labelled to contain a protective atmosphere. O2 and CO2 concentrations varied widely in the rest of the packages. AB and CB counts were high in the leafy vegetable samples varying between 6.2 and 10.6 and 4.2-8.3logcfu/g, respectively. In most of the samples, the AB and CB counts exceeded 10(8) and 10(6)cfu/g, respectively. A positive correlation was observed between the AB and CB counts. E. coli was isolated from 15% of the samples and Yersinia from 33%. L. monocytogenes was isolated from two samples and ail-positive Y. enterocolitica in one. Using PCR, STEC was detected in seven samples, and Salmonella and ail-positive Y. enterocolitica in two samples each. The AB and CB mean values of products originating from different companies varied widely. High AB and CB counts and pathogenic bacteria were detected in ready-to-eat products not needing washing before use. Our study shows that the bacterial quality and safety of packaged fresh leafy vegetables is poor and label information on the packages is inadequate. More studies are needed concerning the impact of a protective atmosphere on bacterial growth, and the impact of washing for removing bacteria. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluation of a Self-Instructional Package for Teaching Tutors to Conduct Discrete-Trials Teaching with Children with Autism

ERIC Educational Resources Information Center

Thomson, Kendra M.; Martin, Garry L.; Fazzio, Daniela; Salem, Sandra; Young, Kristen; Yu, C. T.

2012-01-01

A widely used method for teaching children with autism is applied behavior analysis (ABA), and a main component of ABA programming is discrete-trials teaching (DTT). Using a modified multiple-baseline design across participants, we assessed the effectiveness of a DTT self-instructional package (Fazzio & Martin, 2007) for teaching four pairs of…

7 CFR 205.303 - Packaged products labeled “100 percent organic” or “organic.”

Code of Federal Regulations, 2011 CFR

2011-01-01

... Information § 205.303 Packaged products labeled “100 percent organic” or “organic.” (a) Agricultural products... product, the following: (1) The term, “100 percent organic” or “organic,” as applicable, to modify the name of the product; (2) For products labeled “organic,” the percentage of organic ingredients in the...

Analysis of half diallel mating designs I: a practical analysis procedure for ANOVA approximation.

Treesearch

G.R. Johnson; J.N. King

1998-01-01

Procedures to analyze half-diallel mating designs using the SAS statistical package are presented. The procedure requires two runs of PROC and VARCOMP and results in estimates of additive and non-additive genetic variation. The procedures described can be modified to work on most statistical software packages which can compute variance component estimates. The...

Heterologous Packaging Signals on Segment 4, but Not Segment 6 or Segment 8, Limit Influenza A Virus Reassortment.

PubMed

White, Maria C; Steel, John; Lowen, Anice C

2017-06-01

Influenza A virus (IAV) RNA packaging signals serve to direct the incorporation of IAV gene segments into virus particles, and this process is thought to be mediated by segment-segment interactions. These packaging signals are segment and strain specific, and as such, they have the potential to impact reassortment outcomes between different IAV strains. Our study aimed to quantify the impact of packaging signal mismatch on IAV reassortment using the human seasonal influenza A/Panama/2007/99 (H3N2) and pandemic influenza A/Netherlands/602/2009 (H1N1) viruses. Focusing on the three most divergent segments, we constructed pairs of viruses that encoded identical proteins but differed in the packaging signal regions on a single segment. We then evaluated the frequency with which segments carrying homologous versus heterologous packaging signals were incorporated into reassortant progeny viruses. We found that, when segment 4 (HA) of coinfecting parental viruses was modified, there was a significant preference for the segment containing matched packaging signals relative to the background of the virus. This preference was apparent even when the homologous HA constituted a minority of the HA segment population available in the cell for packaging. Conversely, when segment 6 (NA) or segment 8 (NS) carried modified packaging signals, there was no significant preference for homologous packaging signals. These data suggest that movement of NA and NS segments between the human H3N2 and H1N1 lineages is unlikely to be restricted by packaging signal mismatch, while movement of the HA segment would be more constrained. Our results indicate that the importance of packaging signals in IAV reassortment is segment dependent. IMPORTANCE Influenza A viruses (IAVs) can exchange genes through reassortment. This process contributes to both the highly diverse population of IAVs found in nature and the formation of novel epidemic and pandemic IAV strains. Our study sought to determine the extent to which IAV packaging signal divergence impacts reassortment between seasonal IAVs. Our knowledge in this area is lacking, and insight into the factors that influence IAV reassortment will inform and strengthen ongoing public health efforts to anticipate the emergence of new viruses. We found that the packaging signals on the HA segment, but not the NA or NS segments, restricted IAV reassortment. Thus, the packaging signals of the HA segment could be an important factor in determining the likelihood that two IAV strains of public health interest will undergo reassortment. Copyright © 2017 American Society for Microbiology.

Heterologous Packaging Signals on Segment 4, but Not Segment 6 or Segment 8, Limit Influenza A Virus Reassortment

PubMed Central

White, Maria C.; Steel, John

2017-01-01

ABSTRACT Influenza A virus (IAV) RNA packaging signals serve to direct the incorporation of IAV gene segments into virus particles, and this process is thought to be mediated by segment-segment interactions. These packaging signals are segment and strain specific, and as such, they have the potential to impact reassortment outcomes between different IAV strains. Our study aimed to quantify the impact of packaging signal mismatch on IAV reassortment using the human seasonal influenza A/Panama/2007/99 (H3N2) and pandemic influenza A/Netherlands/602/2009 (H1N1) viruses. Focusing on the three most divergent segments, we constructed pairs of viruses that encoded identical proteins but differed in the packaging signal regions on a single segment. We then evaluated the frequency with which segments carrying homologous versus heterologous packaging signals were incorporated into reassortant progeny viruses. We found that, when segment 4 (HA) of coinfecting parental viruses was modified, there was a significant preference for the segment containing matched packaging signals relative to the background of the virus. This preference was apparent even when the homologous HA constituted a minority of the HA segment population available in the cell for packaging. Conversely, when segment 6 (NA) or segment 8 (NS) carried modified packaging signals, there was no significant preference for homologous packaging signals. These data suggest that movement of NA and NS segments between the human H3N2 and H1N1 lineages is unlikely to be restricted by packaging signal mismatch, while movement of the HA segment would be more constrained. Our results indicate that the importance of packaging signals in IAV reassortment is segment dependent. IMPORTANCE Influenza A viruses (IAVs) can exchange genes through reassortment. This process contributes to both the highly diverse population of IAVs found in nature and the formation of novel epidemic and pandemic IAV strains. Our study sought to determine the extent to which IAV packaging signal divergence impacts reassortment between seasonal IAVs. Our knowledge in this area is lacking, and insight into the factors that influence IAV reassortment will inform and strengthen ongoing public health efforts to anticipate the emergence of new viruses. We found that the packaging signals on the HA segment, but not the NA or NS segments, restricted IAV reassortment. Thus, the packaging signals of the HA segment could be an important factor in determining the likelihood that two IAV strains of public health interest will undergo reassortment. PMID:28331085

21 CFR 177.1600 - Polyethylene resins, carboxyl modified.

Code of Federal Regulations, 2010 CFR

2010-04-01

... resins used in food-packaging adhesives complying with § 175.105 of this chapter. ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Polyethylene resins, carboxyl modified. 177.1600 Section 177.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

21 CFR 177.1600 - Polyethylene resins, carboxyl modified.

Code of Federal Regulations, 2011 CFR

2011-04-01

... resins used in food-packaging adhesives complying with § 175.105 of this chapter. ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Polyethylene resins, carboxyl modified. 177.1600 Section 177.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

21 CFR 177.1600 - Polyethylene resins, carboxyl modified.

Code of Federal Regulations, 2012 CFR

2012-04-01

... resins used in food-packaging adhesives complying with § 175.105 of this chapter. ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Polyethylene resins, carboxyl modified. 177.1600 Section 177.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

21 CFR 177.1600 - Polyethylene resins, carboxyl modified.

Code of Federal Regulations, 2013 CFR

2013-04-01

... resins used in food-packaging adhesives complying with § 175.105 of this chapter. ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Polyethylene resins, carboxyl modified. 177.1600 Section 177.1600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

Large Scale Software Building with CMake in ATLAS

NASA Astrophysics Data System (ADS)

Elmsheuser, J.; Krasznahorkay, A.; Obreshkov, E.; Undrus, A.; ATLAS Collaboration

2017-10-01

The offline software of the ATLAS experiment at the Large Hadron Collider (LHC) serves as the platform for detector data reconstruction, simulation and analysis. It is also used in the detector’s trigger system to select LHC collision events during data taking. The ATLAS offline software consists of several million lines of C++ and Python code organized in a modular design of more than 2000 specialized packages. Because of different workflows, many stable numbered releases are in parallel production use. To accommodate specific workflow requests, software patches with modified libraries are distributed on top of existing software releases on a daily basis. The different ATLAS software applications also require a flexible build system that strongly supports unit and integration tests. Within the last year this build system was migrated to CMake. A CMake configuration has been developed that allows one to easily set up and build the above mentioned software packages. This also makes it possible to develop and test new and modified packages on top of existing releases. The system also allows one to detect and execute partial rebuilds of the release based on single package changes. The build system makes use of CPack for building RPM packages out of the software releases, and CTest for running unit and integration tests. We report on the migration and integration of the ATLAS software to CMake and show working examples of this large scale project in production.

Endothelial protection: avoiding air bubble formation at the phacoemulsification tip.

PubMed

Kim, Eung Kweon; Cristol, Stephen M; Kang, Shin J; Edelhauser, Henry F; Yeon, Dong-Soo; Lee, Jae Bum

2002-03-01

To investigate the conditions under which bubbles form during phacoemulsification. Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea. In the first part of the study, the partial pressure of oxygen (pO(2)) was used as a surrogate measure for the partial pressure of air. Irrigation solutions packaged in glass and plastic containers were studied. A directly vented glass bottle was also tested. The pO(2) of the various irrigation solutions was measured as the containers were emptied. In the second part, phacoemulsification procedures were performed in rabbit eyes with different power settings and different irrigation solutions. Intracameral bubble formation during the procedure was recorded. Following the phacoemulsification procedures, the corneas were stained for F-actin and examined for endothelial injury. The initial pO(2) in irrigation solutions packaged in glass bottles was about half that at atmospheric levels; in solutions packaged in plastic, it was at atmospheric levels. As irrigation solutions were drained from the container, the pO(2) of the solution tended to rise toward atmospheric levels. The rate of pO(2) increase was markedly reduced by using a directly vented glass bottle. In the phacoemulsification procedures, bubble formation was most likely to occur with higher pO(2) and higher power settings. Observation of bubbles by the surgeon was highly correlated with endothelial damage. Keeping the pO(2) low reduced the risk of endothelial damage, especially at higher phacoemulsification powers. The packaging of irrigation solutions was the most important factor in controlling the initial pO(2) of the solution. The pO(2) can be minimized throughout a phacoemulsification procedure by using a directly vented glass bottle.

Atmospheric cold plasma inactivation of Escherichia coli 0157:H7 and aerobic microorganisms in cold-stored romaine lettuce packaged in a commerical polyethylene terephthalate container

USDA-ARS?s Scientific Manuscript database

Leafy greens continue to be a significant vector for foodborne pathogens, including Escherichia coli O157:H7. Dielectric barrier discharge atmospheric cold plasma (ACP) treatment is a promising method for microbial decontamination of produce. An important aspect of this technology is the potential f...

Method and apparatus for container leakage testing

DOEpatents

Kronberg, James W.

1995-01-01

An apparatus for use in one-hundred percent leak testing of food containers used in conjunction with a tracer gas. The apparatus includes a shell with entrance and exit air locks to create a controlled atmosphere through which a series of containers is conveyed by a conveyor belt. The pressure in the shell is kept lower than the pressure in the containers and the atmosphere is made to flow with the containers so that a tracer gas placed in the packages before sealing them will leak more readily, but the leaked tracer gas will remain associated with the leaking package as it moves through the shell. The leaks are detected with a sniffer probe in fluid communication with a gas chromatograph. The gas chromatograph issues a signal when it detects a leak to an ejector that will eject the leaking container from the conveyor. The system is timed so that the series of containers can move continuously into and out of the shell, past the probe and the ejector, without stopping, yet each package is tested for leaks and removed if leaking.

Characterization of the Resource Potential of Martian Soil using the Integrated Dust/Soil Experiment Package (IDEP)

NASA Technical Reports Server (NTRS)

Cooper, Bonnie L.; Mckay, David S.; Allen, Carlton C.; Hoffman, John H.; Gittleman, Mark E.

1997-01-01

The Integrated Dust/Soil Experiment Package (IDEP) is a suite of instruments that can detect and quantify the abundances of useful raw materials on Mars. We focus here on its capability for resource characterization in the martian soil; however, it is also capable of detecting and quantifying gases in the atmosphere. This paper describes the scientific rationale and the engineering design behind the IDEP.

Passive millimeter wave simulation in blender

NASA Astrophysics Data System (ADS)

Murakowski, Maciej

Imaging in the millimeter wave (mmW) frequency range is being explored for applications where visible or infrared (IR) imaging fails, such as through atmospheric obscurants. However, mmW imaging is still in its infancy and imager systems are still bulky, expensive, and fragile, so experiments on imaging in real-world scenarios are difficult or impossible to perform. Therefore, a simulation system capable of predicting mmW phenomenology would be valuable in determining the requirements (e.g. resolution or noise floor) of an imaging system for a particular scenario and aid in the design of such an imager. Producing simulation software for this purpose is the objective of the work described in this thesis. The 3D software package Blender was modified to simulate the images produced by a passive mmW imager, based on a Geometrical Optics approach. Simulated imagery was validated against experimental data and the software was applied to novel imaging scenarios. Additionally, a database of material properties for use in the simulation was collected.

Spoilage and shelf-life extension of fresh fish and shellfish.

PubMed

Ashie, I N; Smith, J P; Simpson, B K

1996-01-01

Fresh fish and shellfish are highly perishable products due to their biological composition. Under normal refrigerated storage conditions, the shelf life of these products is limited by enzymatic and microbiological spoilage. However, with increasing consumer demands for fresh products with extended shelf life and increasing energy costs associated with freezing and frozen storage, the fish-processing industry is actively seeking alternative methods of shelf life preservation and marketability of fresh, refrigerated fish and at the same time economizing on energy costs. Additional methods that could fulfill these objectives include chemical decontamination, low-dose irradiation, ultra-high pressure, and modified atmosphere packaging (MAP). This review focuses on the biochemical and microbiological composition of fresh fish/shellfish, the spoilage patterns in these products, factors influencing spoilage, and the combination treatments that can be used in conjunction with refrigeration to extend the shelf life and keeping quality of fresh fish/shellfish. The safety concerns of minimally processed/MAP fish, specifically with respect to the growth of Clostridium botulinum type E, is also addressed.

Alternative natural seasoning to improve the microbial stability of low-salt beef patties.

PubMed

García-Lomillo, Javier; González-SanJosé, M A Luisa; Del Pino-García, Raquel; Rivero-Pérez, M A Dolores; Muñiz-Rodríguez, Pilar

2017-07-15

The meat industry is seeking new strategies to reduce the sodium content of meat products without shortening their shelf-life. Natural seasonings as salt alternatives are more appreciated than chemical preservatives and also enable the incorporation of interesting nutrients. The present work studies the potential of a new red wine pomace seasoning (RWPS), derived from wine pomace, to inhibit spoilage growth in beef patties with different salt levels (2%, 1.5% and 1%) held in storage at 4°C. The use of RWPS (2% w/w) improved the microbial stability of the patties, delaying total aerobic mesophilic, and lactic acid bacteria growth, especially in samples with low salt levels. Satisfactory results were obtained in modified-atmosphere and air-packaged patties. RWPS also enabled the incorporation of fiber and phenolic compounds, and increased potassium and calcium levels. In summary, RWPS presented an interesting potential as a seasoning in meat products, enabling salt reduction without compromising their microbial stability. Copyright © 2017 Elsevier Ltd. All rights reserved.

Concentration of biologically active polyamines in meat and liver of sheep and lambs after slaughter and their changes in mutton during storage and cooking.

PubMed

Dadáková, Eva; Pelikánová, Tamara; Kalač, Pavel

2011-02-01

Putrescine (PUT), spermidine (SPD) and spermine (SPM) concentrations using a UPLC method, in chilled mutton, lamb and livers 24 h after slaughter were determined. PUT concentrations were quantifiable only in some samples. Mean SPD concentrations were 4-6, 13.5 and 16.8 mg kg-1 in the meats, sheep and lamb livers, respectively. The respective SPM concentrations were 17-25, 128 and 79 mg kg-1. SPD and SPM losses of about one fifth and half of the initial level, respectively, were apparent in mutton loins stored at -18°C for 6 months. Significant losses of SPD and SPM were found in mutton loins stored aerobically, vacuum-packaged or in a modified atmosphere at +2°C. Boiling and stewing of mutton legs caused SPD and SPM losses of about 40% and roasting of about 60% of the initial content. Copyright © 2010 Elsevier Ltd. All rights reserved.

Maintaining antioxidant potential of fresh fruits and vegetables after harvest.

PubMed

Villa-Rodriguez, Jose A; Palafox-Carlos, H; Yahia, Elhadi M; Ayala-Zavala, J Fernando; Gonzalez-Aguilar, Gustavo A

2015-01-01

The consumption of fruits and vegetables has increased in the past few years, not only because of their attractive sensorial properties, but also for their nutritional and health benefits. Antioxidants are compounds found in fresh fruits and vegetables, and evidence of their role in the prevention of degenerative diseases is continuously emerging. However, the antioxidants in some fruits and vegetables can be lost during handling after harvest, even during minimal processing and storage. In this sense, postharvest treatments are needed to preserve the quality and antioxidant potential of fresh produce. Postharvest treatments and technologic strategies (including ultraviolet light, controlled and modified atmospheres, heat treatments, and application of natural compounds, such as edible coatings, active packaging, microencapsulation, and nanoemulsion) have shown positive and promising results to maintain fruit and vegetable antioxidant potential. The purpose of this review is to analyze and propose the application of postharvest strategies to maintain, or even improve, the antioxidant status of fruits and vegetables, thus offering options to maximize health benefits to consumers.

Modeling Atmospheric Transport for Greenhouse Gas Observations within the Urban Dome

NASA Astrophysics Data System (ADS)

Nehrkorn, T.; Sargent, M. R.; Wofsy, S. C.

2016-12-01

Observations of CO2, CH4, and other greenhouse gases (GHGs) within the urban dome of major cities generally show large enhancements over background values, and large sensitivity to surface fluxes (as measured by the footprints computed by Lagrangian Particle Dispersion Models, LPDMs) within the urban dome. However, their use in top-down inversion studies to constrain urban emission estimates is complicated by difficulties in proper modeling of the atmospheric transport. We are conducting experiments with the Weather Research and Forecast model (WRF) coupled to the STILT LPDM to improve model simulation of atmospheric transport on spatial scales of a few km in urban domains, because errors in transport on short time/space scales are amplified by the patchiness of GHG emissions and may engender systematic errors of simulated concentrations.We are evaluating the quality of the meteorological simulations from model configurations with different resolutions and PBL packages, using both standard and non-standard (Lidar PBL height and ACARS aircraft profile) observations. To take into account the effect of building scale eddies for observations located on top of buildings, we are modifying the basic STILT algorithm for the computation of footprints by replacing the nominal receptor height by an effective sampling height. In addition, the footprint computations for near-field emissions make use of the vertical particle spread within the LPDM to arrive at a more appropriate estimate of mixing heights in the immediate vicinity of receptors. We present the effect of these and similar modifications on simulated concentrations and their level of agreement with observed values.

The Neutral Gas and Ion Mass Spectrometer on the Mars Atmosphere and Volatile Evolution Mission

NASA Technical Reports Server (NTRS)

Mahaffy, Paul R.; Benna, Mehdi; King, Todd; Harpold, Daniel N.; Arvey, Robert; Barciniak, Michael; Bendt, Mirl; Carrigan, Daniel; Errigo, Therese; Holmes, Vincent;

Meso-scale controlled motion for a microfluidic drop ejector.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galambos, Paul C.; Givler, Richard C.; Pohl, Kenneth Roy

2004-12-01

The objective of this LDRD was to develop a uniquely capable, novel droplet solution based manufacturing system built around a new MEMS drop ejector. The development all the working subsystems required was completed, leaving the integration of these subsystems into a working prototype still left to accomplish. This LDRD report will focus on the three main subsystems: (1) MEMS drop ejector--the MEMS ''sideshooter'' effectively ejected 0.25 pl drops at 10 m/s, (2) packaging--a compact ejector package based on a modified EMDIP (Electro-Microfluidic Dual In-line Package--SAND2002-1941) was fabricated, and (3) a vision/stage system allowing precise ejector package positioning in 3 dimensionsmore » above a target was developed.« less

Skylab EREP Investigations Summary

NASA Technical Reports Server (NTRS)

Pierson, W. J. (Editor)

1978-01-01

The problems in the areas of agriculture, range and forestry; land use and cartography; geology and hydrology; oceans atmosphere, and data analysis techniques were investigated and summarized using Earth Resources Experiment Package (EREP) data.

Applications of multigrid software in the atmospheric sciences

NASA Technical Reports Server (NTRS)

Adams, J.; Garcia, R.; Gross, B.; Hack, J.; Haidvogel, D.; Pizzo, V.

1992-01-01

Elliptic partial differential equations from different areas in the atmospheric sciences are efficiently and easily solved utilizing the multigrid software package named MUDPACK. It is demonstrated that the multigrid method is more efficient than other commonly employed techniques, such as Gaussian elimination and fixed-grid relaxation. The efficiency relative to other techniques, both in terms of storage requirement and computational time, increases quickly with grid size.

LADEE Mission Update 2 (Beginning of Science Operations) Reporter Package

NASA Image and Video Library

2013-11-19

NASA's Lunar Atmosphere and Dust Environment Explorer, or LADEE, spacecraft has completed the check-out phase of its mission and has begun science operations around the moon. All the science instruments on-board have been examined by the LADEE team and have been cleared to begin collecting and analyzing the dust in the exosphere, or very thin atmosphere, that surrounds the moon.

Specific inhibition of Photobacterium phosphoreum extends the shelf life of modified-atmosphere-packed cod fillets.

PubMed

Dalgaard, P; Garcia Munoz, L; Mejlholm, O

1998-09-01

Inhibition of the specific spoilage organism, Photobacterium phosphoreum, was studied in model substrates and in modified-atmosphere-packed cod fillets. The objective was to determine how inhibition of this organism influenced spoilage. The spoilage reactions limiting shelf life were studied rather than the development of a new product. In naturally contaminated modified-atmosphere-packed cod fillets, 500 ppm Na2CaEDTA reduced the growth rate of P. phosphoreum by 40% and shelf life was increased proportionally by 40%, from 15 to 17 days to 21 to 23 days at 0 degree C. In aerobically stored cod fillets other microorganisms were responsible for spoilage and Na2CaEDTA had no effect on shelf life. The extension of the shelf life of modified-atmosphere-packed cod therefore was a result of the reduced growth of P. phosphoreum and no other microbial or nonmicrobial spoilage reactions limited shelf life. These results confirmed P. phosphoreum as the specific spoilage organism in modified-atmosphere-packed cod and showed the organism to have an extensive spoilage domain. Consequently, any preservation procedure able to reduce growth of P. phosphoreum is likely to extend shelf life of packed cod. However, the effect of different inhibitory compounds in model systems as well as results from packed cod indicated the need to include product studies in the screening of antimicrobials and in the development of preservation procedures.

21 CFR 176.130 - Anti-offset substances.

Code of Federal Regulations, 2013 CFR

2013-04-01

... in printing and decorating paper and paperboard used for food packaging in accordance with the...: Substances Limitations Carbon tetrachloride Methyl hydrogen polysiloxanes Industrial starch—modified...

21 CFR 176.130 - Anti-offset substances.

Code of Federal Regulations, 2012 CFR

2012-04-01

... in printing and decorating paper and paperboard used for food packaging in accordance with the...: Substances Limitations Carbon tetrachloride Methyl hydrogen polysiloxanes Industrial starch—modified...

21 CFR 176.130 - Anti-offset substances.

Code of Federal Regulations, 2010 CFR

2010-04-01

... in printing and decorating paper and paperboard used for food packaging in accordance with the...: Substances Limitations Carbon tetrachloride Methyl hydrogen polysiloxanes Industrial starch—modified...

21 CFR 176.130 - Anti-offset substances.

Code of Federal Regulations, 2011 CFR

2011-04-01

... in printing and decorating paper and paperboard used for food packaging in accordance with the...: Substances Limitations Carbon tetrachloride Methyl hydrogen polysiloxanes Industrial starch—modified...

Implementation of the NCAR (National Centre for Atmospheric Research) Graphics Package at ARL (Aeronautical Research Laboratory).

DTIC Science & Technology

1988-01-01

VELVCT. .. .. ... ... ... .... ... 57 E.5 Arguments for Subroutine EZVEC .. .. .. ... ... ... ... .... 59 E.6 Using VELVCT with the Mapping Packege EZMAP...VELVCT with the Mapping Packege EZMAP Using this routine to put vectors on an arbitrary background drawn by EZMAP is a bit tricky. The arithmetic...squares solutions to overdetermined linear systems. 129 K.2 The "Fishpack" Package This packege was included on the NCAR distribution tape. It consists of

Enhanced Shielding Performance of HLW Storage Packages via Multi- Component Coatings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winfrey, Leigh

The steel coatings developed here prevent water, dirt, and chemical contaminants from the atmosphere or soil from making contact with waste packages that would damage and weaken them during long-term storage. In addition, through this project we demonstrated that a range of coatings have this capability, will survive in the environment they will be used in, and can be deposited readily on large surfaces which is critical for their use in waste storage.

Degradation of carotenoids in dehydrated pumpkins as affected by different storage conditions.

PubMed

Song, Jiangfeng; Wei, Qiuyu; Wang, Xiaoping; Li, Dajing; Liu, Chunquan; Zhang, Min; Meng, Lili

2018-05-01

The degradation kinetics of carotenoids in dehydrated pumpkins, stored at 4, 25, and 40 °C under air or controlled atmosphere conditions (N 2 ), was evaluated using reversed-phase high performance liquid chromatography coupled with diode array and mass spectrometry detectors. The degradations of predominant carotenoids including β-carotene, α-carotene and lutein depended on the storage temperature, the storage duration as well as the presence of oxygen, which was following the first-order kinetics. The temperature dependence of reaction constants were well explained by the Arrhenius relationship. The activation energy (Ea) for carotenoids degradation ranged from 23.69 kJ/mol for lutein in N 2 -packaged dehydrated pumpkins to 13.82 kJ/mol for β-carotene in air-packaged samples. Lutein was less degradable than α-carotene and β-carotene in dehydrated pumpkins during storage. Higher all-E-carotenoid degradation in N 2 -packaged dehydrated pumpkins stored at 40 °C occurred than that stored at lower temperature under N 2 or air storage, and those storage conditions were beneficial to the formation of Z-isomers (e.g., 15-Z-β-carotene and 13-Z-β-carotene). Storage under N 2 at 4 °C enhanced the retention of all-E-carotenoids in dehydrated pumpkins. Thus, package atmosphere should be paid more attention during long-term storage. Copyright © 2018 Elsevier Ltd. All rights reserved.

MIFT: GIFT Combinatorial Geometry Input to VCS Code

DTIC Science & Technology

1977-03-01

r-w w-^ H ^ß0318is CQ BRL °RCUMr REPORT NO. 1967 —-S: ... MIFT: GIFT COMBINATORIAL GEOMETRY INPUT TO VCS CODE Albert E...TITLE (and Subtitle) MIFT: GIFT Combinatorial Geometry Input to VCS Code S. TYPE OF REPORT & PERIOD COVERED FINAL 6. PERFORMING ORG. REPORT NUMBER...Vehicle Code System (VCS) called MORSE was modified to accept the GIFT combinatorial geometry package. GIFT , as opposed to the geometry package

Implementation of interconnect simulation tools in spice

NASA Technical Reports Server (NTRS)

Satsangi, H.; Schutt-Aine, J. E.

1993-01-01

Accurate computer simulation of high speed digital computer circuits and communication circuits requires a multimode approach to simulate both the devices and the interconnects between devices. Classical circuit analysis algorithms (lumped parameter) are needed for circuit devices and the network formed by the interconnected devices. The interconnects, however, have to be modeled as transmission lines which incorporate electromagnetic field analysis. An approach to writing a multimode simulator is to take an existing software package which performs either lumped parameter analysis or field analysis and add the missing type of analysis routines to the package. In this work a traditionally lumped parameter simulator, SPICE, is modified so that it will perform lossy transmission line analysis using a different model approach. Modifying SPICE3E2 or any other large software package is not a trivial task. An understanding of the programming conventions used, simulation software, and simulation algorithms is required. This thesis was written to clarify the procedure for installing a device into SPICE3E2. The installation of three devices is documented and the installations of the first two provide a foundation for installation of the lossy line which is the third device. The details of discussions are specific to SPICE, but the concepts will be helpful when performing installations into other circuit analysis packages.

Effect of Grinding at Modified Atmosphere or Vacuum on Browning, Antioxidant Capacities, and Oxidative Enzyme Activities of Apple.

PubMed

Kim, Ah-Na; Lee, Kyo-Yeon; Kim, Hyun-Jin; Chun, Jiyeon; Kerr, William L; Choi, Sung-Gil

2018-01-01

This study evaluated the effects of grinding at atmospheric pressure (control), under vacuum (∼2.67 kPa), or with modified atmosphere (N 2 and CO 2 ) on the browning, antioxidant activity, phenolics, and oxidative enzyme activity of apples as a function of time. The control group was affected most, showing distinct browning and losing most of the antioxidant activity and concentrations of the main phenolic compounds. The modified atmosphere groups retained color, antioxidant activity, and phenolic compounds better than the control group. Least changes were obtained with vacuum grinding, particularly in terms of preventing enzymatic browning and oxidation of antioxidants apples. At 12 h after grinding, vacuum-ground apples retained total phenolic contents 5.32, 1.54, and 1.49 times higher than control, nitrogen gas, and carbon dioxide gas-ground samples, respectively. The oxidative enzyme activity, including that of polyphenol oxidase and peroxidase, decreased in the control and modified atmosphere group, but they were maintained in the samples ground under the vacuum. In this study, we found that grinding with modified atmosphere or vacuum conditions could effectively prevent browning as well as loss of phenolic compounds and antioxidant activity of ground apples. These results can help scientists and engineers build better grinding systems for retaining nutrient and quality factors of ground apples. In addition, these results may be useful to other fruit and vegetable industries that wish to retain fresh-like quality and nutritional value during grinding and storage. © 2017 Institute of Food Technologists®.

Modified atmosphere treatments as a potential disinfestation technique for arthropod pests in greenhouses.

PubMed

Held, D W; Potter, D A; Gates, R S; Anderson, R G

2001-04-01

Incidental transport of arthropods on plant material can be a significant mode of pest entry into greenhouses. We evaluated the use of controlled atmosphere treatments as a potential way to eliminate arthropod pests on plant propagules (i.e., cuttings or small rooted plants). Lethal exposures to CO2 or N2 were determined for common greenhouse pests including fungus gnat larvae, Bradysia sp.; green peach aphid, Myzus persicae (Sulzer); sweetpotato whitefly, Bemisia sp.; twospotted spider mite, Tetranychus urticae Koch; and western flower thrips, Frankliniella occidentalis (Pergande). We also studied the effect of pest species, life stage, and presence or absence of plants on efficacy of modified atmosphere treatments. Finally, effects of modified atmospheres on plant quality were evaluated for several bedding plant species including begonia, Begonia semperflorens-cultorum Hort. 'Cocktail Series', chrysanthemum, Dendranthema grandiflora Tzvelev., geranium, Pelargonium X hortorum L.H. Bailey, and impatiens, Impatiens wallerana Hook f., and among cultivars of geranium and chrysanthemum. Exposure for 12-18 h to >99% N2 or CO2 caused complete mortality of aphids, mites, thrips, and whiteflies. Fungus gnat larvae were more tolerant of hypoxic conditions. Adult mites and eggs were equally susceptible. For most pests, there was no difference in response to atmospheres modified by CO2 or N2. However, there was variation in response among plant species and cultivars, with effects ranging from delayed flowering to mortality. Despite the possibility of adverse effects on some plants, this work indicates that use of modified atmospheres has potential to eliminate arthropod pests on plant propagules before they are introduced into greenhouses.

Effects of sintering atmosphere on the physical and mechanical properties of modified BOF slag glass

NASA Astrophysics Data System (ADS)

Dai, Wen-bin; Li, Yu; Cang, Da-qiang; Zhou, Yuan-yuan; Fan, Yong

2014-05-01

This study proposes an efficient way to utilize all the chemical components of the basic oxygen furnace (BOF) slag to prepare high value-added glass-ceramics. A molten modified BOF slag was converted from the melting BOF slag by reducing it and separating out iron component in it, and the modified BOF slag was then quenched in water to form glasses with different basicities. The glasses were subsequently sintered in the temperature range of 600-1000°C in air or nitrogen atmosphere for 1 h. The effects of different atmospheres on the physical and mechanical properties of sintered samples were studied by using differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM) and by conducting experiment on evaluating the sintering shrinkage, water absorption and bulk density. It is found that the kinetics of the sintering process is significantly affected by sintering atmosphere. In particular, compared with sintering in air atmosphere, sintering in N2 atmosphere promotes the synergistic growth of pyroxene and melilite crystalline phases, which can contribute to better mechanical properties and denser microstructure.

UNDERSTANDING AND REDUCING THE UNCERTAINTY ASSOCIATED WITH THE EFFECT OF ATMOSPHERIC PARTICLES ON CLOUDS AND CLIMATE

EPA Science Inventory

I predict that human-generated particles have modified clouds and cooled climate, somewhat masking the effect of greenhouse gases and that these particles have also modified the amount of sunlight reaching the ground, changing the thermodynamic cycles in the atmosphere. Wi...

Biosynthesis and Characterization of AgNPs–Silk/PVA Film for Potential Packaging Application

PubMed Central

Tao, Gang; Cai, Rui; Wang, Yejing; Song, Kai; Guo, Pengchao; Zhao, Ping; Zuo, Hua; He, Huawei

2017-01-01

Bionanocomposite packaging materials have a bright future for a broad range of applications in the food and biomedical industries. Antimicrobial packaging is one of the bionanocomposite packaging materials. Silver nanoparticle (AgNP) is one of the most attractive antimicrobial agents for its broad spectrum of antimicrobial activity against microorganisms. However, the traditional method of preparing AgNPs-functionalized packaging material is cumbersome and not environmentally friendly. To develop an efficient and convenient biosynthesis method to prepare AgNPs-modified bionanocomposite material for packaging applications, we synthesized AgNPs in situ in a silk fibroin solution via the reduction of Ag+ by the tyrosine residue of fibroin, and then prepared AgNPs–silk/poly(vinyl alcohol) (PVA) composite film by blending with PVA. AgNPs were synthesized evenly on the surface or embedded in the interior of silk/PVA film. The prepared AgNPs–silk/PVA film exhibited excellent mechanical performance and stability, as well as good antibacterial activity against both Gram-negative and Gram-positive bacteria. AgNPs–silk/PVA film offers more choices to be potentially applied in the active packaging field. PMID:28773026

Biosynthesis and Characterization of AgNPs-Silk/PVA Film for Potential Packaging Application.

PubMed

Tao, Gang; Cai, Rui; Wang, Yejing; Song, Kai; Guo, Pengchao; Zhao, Ping; Zuo, Hua; He, Huawei

2017-06-17

Bionanocomposite packaging materials have a bright future for a broad range of applications in the food and biomedical industries. Antimicrobial packaging is one of the bionanocomposite packaging materials. Silver nanoparticle (AgNP) is one of the most attractive antimicrobial agents for its broad spectrum of antimicrobial activity against microorganisms. However, the traditional method of preparing AgNPs-functionalized packaging material is cumbersome and not environmentally friendly. To develop an efficient and convenient biosynthesis method to prepare AgNPs-modified bionanocomposite material for packaging applications, we synthesized AgNPs in situ in a silk fibroin solution via the reduction of Ag⁺ by the tyrosine residue of fibroin, and then prepared AgNPs-silk/poly(vinyl alcohol) (PVA) composite film by blending with PVA. AgNPs were synthesized evenly on the surface or embedded in the interior of silk/PVA film. The prepared AgNPs-silk/PVA film exhibited excellent mechanical performance and stability, as well as good antibacterial activity against both Gram-negative and Gram-positive bacteria. AgNPs-silk/PVA film offers more choices to be potentially applied in the active packaging field.

Reliability of high I/O high density CCGA interconnect electronic packages under extreme thermal environments

NASA Astrophysics Data System (ADS)

Ramesham, Rajeshuni

2012-03-01

Ceramic column grid array (CCGA) packages have been increasing in use based on their advantages such as high interconnect density, very good thermal and electrical performances, compatibility with standard surfacemount packaging assembly processes, and so on. CCGA packages are used in space applications such as in logic and microprocessor functions, telecommunications, payload electronics, and flight avionics. As these packages tend to have less solder joint strain relief than leaded packages or more strain relief over lead-less chip carrier packages, the reliability of CCGA packages is very important for short-term and long-term deep space missions. We have employed high density CCGA 1152 and 1272 daisy chained electronic packages in this preliminary reliability study. Each package is divided into several daisy-chained sections. The physical dimensions of CCGA1152 package is 35 mm x 35 mm with a 34 x 34 array of columns with a 1 mm pitch. The dimension of the CCGA1272 package is 37.5 mm x 37.5 mm with a 36 x 36 array with a 1 mm pitch. The columns are made up of 80% Pb/20%Sn material. CCGA interconnect electronic package printed wiring polyimide boards have been assembled and inspected using non-destructive x-ray imaging techniques. The assembled CCGA boards were subjected to extreme temperature thermal atmospheric cycling to assess their reliability for future deep space missions. The resistance of daisy-chained interconnect sections were monitored continuously during thermal cycling. This paper provides the experimental test results of advanced CCGA packages tested in extreme temperature thermal environments. Standard optical inspection and x-ray non-destructive inspection tools were used to assess the reliability of high density CCGA packages for deep space extreme temperature missions.

Further Testing of an Amine-based Pressure-Swing System for Carbon Dioxide and Humidity Control

NASA Technical Reports Server (NTRS)

Lin, Amy; Smith, Frederick; Sweterlitsch, Jeffrey; Nalette, Tim A.; Papale, William

2008-01-01

In a crewed spacecraft environment, atmospheric carbon dioxide (CO2) and moisture control are crucial. Hamilton Sundstrand has developed a stable and efficient amine-based CO2 and water vapor sorbent, SA9T, that is well suited for use in a spacecraft environment. The sorbent is efficiently packaged in pressure-swing regenerable beds that are thermally linked to improve removal efficiency and minimize vehicle thermal loads. Flows are all controlled with a single spool valve. This technology has been baselined for the new Orion spacecraft. However, more data was needed on the operational characteristics of the package in a simulated spacecraft environment. A unit was therefore tested with simulated metabolic loads in a closed chamber at Johnson Space Center during the last third of 2006. Those test results were reported in a 2007 ICES paper. A second test article was incorporated for a third phase of testing, and that test article was modified to allow pressurized gas purge regeneration on the launch pad in addition to the standard vacuum regeneration in space. Metabolic rates and chamber volumes were also adjusted to reflect current programmatic standards. The third phase of tests was performed during the spring and summer of 2007. Tests were run with a range of operating conditions, varying: cycle time, vacuum pressure (or purge gas flow rate), air flow rate, and crew activity levels. Results of this testing are presented and potential flight operational strategies discussed.

The Cooperative VAS Program with the Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

Diak, George R.; Menzel, W. Paul

1988-01-01

Work was divided between the analysis/forecast model development and evaluation of the impact of satellite data in mesoscale numerical weather prediction (NWP), development of the Multispectral Atmospheric Mapping Sensor (MAMS), and other related research. The Cooperative Institute for Meteorological Satellite Studies (CIMSS) Synoptic Scale Model (SSM) has progressed from a relatively basic analysis/forecast system to a package which includes such features as nonlinear vertical mode initialization, comprehensive Planetary Boundary Layer (PBL) physics, and the core of a fully four-dimensional data assimilation package. The MAMS effort has produced a calibrated visible and infrared sensor that produces imager at high spatial resolution. The MAMS was developed in order to study small scale atmospheric moisture variability, to monitor and classify clouds, and to investigate the role of surface characteristics in the production of clouds, precipitation, and severe storms.

NLTE Model Atmospheres for Super-Soft X-ray Sources

NASA Astrophysics Data System (ADS)

Rauch, Thomas; Werner, Klaus

2009-09-01

Spectral analysis by means of fully line-blanketed Non-LTE model atmospheres has arrived at a high level of sophistication. The Tübingen NLTE Model Atmosphere Package (TMAP) is used to calculate plane-parallel NLTE model atmospheres which are in radiative and hydrostatic equilibrium. Although TMAP is not especially designed for the calculation of burst spectra of novae, spectral energy distributions (SEDs) calculated from TMAP models are well suited e.g. for abundance determinations of Super Soft X-ray Sources like nova V4743 Sgr or line identifications in observations of neutron stars with low magnetic fields in low-mass X-ray binaries (LMXBs) like EXO 0748-676.

Theoretical White Dwarf Spectra on Demand: TheoSSA

NASA Astrophysics Data System (ADS)

Ringat, E.; Rauch, T.

2010-11-01

In the last decades, a lot of progress was made in spectral analysis. The quality (e.g. resolution, S/N ratio) of observed spectra has improved much and several model-atmosphere codes were developed. One of these is the ``Tübingen NLTE Model-Atmosphere Package'' (TMAP), that is a highly developed program for the calculation of model atmospheres of hot, compact objects. In the framework of the German Astrophysical Virtual Observatory (GAVO), theoretical spectral energy distributions (SEDs) can be downloaded via TheoSSA. In a pilot phase, TheoSSA is based on TMAP model atmospheres. We present the current state of this VO service.

The results of pre-design studies on the development of a new design of gas turbine compressor package of GPA-C-16 type

NASA Astrophysics Data System (ADS)

Smirnov, A. V.; Chobenko, V. M.; Shcherbakov, O. M.; Ushakov, S. M.; Parafiynyk, V. P.; Sereda, R. M.

2017-08-01

The article summarizes the results of analysis of data concerning the operation of turbocompressor packages at compressor stations for the natural gas transmission system of Ukraine. The basic requirements for gas turbine compressor packages used for modernization and reconstruction of compressor stations are considered. Using a 16 MW gas turbine package GPA-C-16S/76-1,44M1 as an example, the results of pre-design studies and some technical solutions that improve the energy efficiency of gas turbine compressor packages and their reliability, as well as its environmental performance are given. In particular, the article deals with the matching of performance characteristics of a centrifugal compressor (hereinafter compressor) and gas turbine drive to reduce fuel gas consumption; as well as application of energy efficient technologies, in particular, exhaust gas heat recovery units and gas-oil heat exchangers in turbocompressor packages oil system; as well as reducing emissions of carbon monoxide into the atmosphere using a catalytic exhaust system. Described technical solutions can be used for development of other types of gas turbine compressor packages.

Geant4 Modifications for Accurate Fission Simulations

NASA Astrophysics Data System (ADS)

Tan, Jiawei; Bendahan, Joseph

Monte Carlo is one of the methods to simulate the generation and transport of radiation through matter. The most widely used radiation simulation codes are MCNP and Geant4. The simulation of fission production and transport by MCNP has been thoroughly benchmarked. There is an increasing number of users that prefer using Geant4 due to the flexibility of adding features. However, it has been found that Geant4 does not have the proper fission-production cross sections and does not produce the correct fission products. To achieve accurate results for studies in fissionable material applications, Geant4 was modified to correct these inaccuracies and to add new capabilities. The fission model developed by the Lawrence Livermore National Laboratory was integrated into the neutron-fission modeling package. The photofission simulation capability was enabled using the same neutron-fission library under the assumption that nuclei fission in the same way, independent of the excitation source. The modified fission code provides the correct multiplicity of prompt neutrons and gamma rays, and produces delayed gamma rays and neutrons with time and energy dependencies that are consistent with ENDF/B-VII. The delayed neutrons are now directly produced by a custom package that bypasses the fragment cascade model. The modifications were made for U-235, U-238 and Pu-239 isotopes; however, the new framework allows adding new isotopes easily. The SLAC nuclear data library is used for simulation of isotopes with an atomic number above 92 because it is not available in Geant4. Results of the modified Geant4.10.1 package of neutron-fission and photofission for prompt and delayed radiation are compared with ENDFB-VII and with results produced with the original package.

Scintillation index of higher order mode laser beams in strong turbulence

NASA Astrophysics Data System (ADS)

Baykal, Yahya

2017-03-01

The scintillation index of higher order laser modes is examined in strong atmospheric turbulence. In our formulation, modified Rytov theory is employed with the inclusion of existing modified turbulence spectrum which presents the atmospheric turbulence spectrum as a linear filter having refractive and diffractive spatial frequency cutoffs. Variations of the scintillation index in strong atmospheric turbulence are shown against the weak turbulence plane wave scintillation index for various higher order laser modes of different sizes. Use of higher order modes in optical wireless communication links operating in strongly turbulent atmosphere is found to be advantageous in reducing the scintillation noise.

Protein Oxidation and Sensory Quality of Brine-Injected Pork Loins Added Ascorbate or Extracts of Green Tea or Maté during Chill-Storage in High-Oxygen Modified Atmosphere.

PubMed

Jongberg, Sisse; Tørngren, Mari Ann; Skibsted, Leif H

2018-01-15

Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork chops sold for retail, but may affect protein oxidation, while plant extracts are potential substitutes. Methods: Brine-injected pork chops (weight-gain ~12%, NaCl ~0.9%) prepared with ascorbate (225 ppm), green tea extract (25 ppm gallic acid equivalents (GAE)), or maté extract (25 ppm GAE) stored (5 °C, seven days) in high-oxygen atmosphere packaging (MAP: 80% O₂ and 20% CO₂) were analyzed for color changes, sensory quality, and protein oxidation compared to a control without antioxidant. Results: No significant differences were observed for green tea and maté extracts as compared to ascorbate when evaluated based on lipid oxidation derived off-flavors, except for stale flavor, which maté significantly reduced. All treatments increased the level of the protein oxidation product, α-aminoadipic semialdehyde as compared to the control, and ascorbate was further found to increase thiol loss and protein cross-linking, with a concomitant decrease in the sensory perceived tenderness. Conclusions: Green tea and maté were found to equally protect against lipid oxidation derived off-flavors, and maté showed less prooxidative activity towards proteins as compared to ascorbate, resulting in more tender meat. Maté is a valuable substitute for ascorbate in brine-injected pork chops.

Inoculation density is affecting growth conditions of Listeria monocytogenes on fresh cut lettuce.

PubMed

McManamon, Oisin; Scollard, Johann; Schmalenberger, Achim

2017-11-27

Listeria monocytogenes is a particular risk for the ready-to-eat food sector because of its ability to grow in various environmental conditions. In the literature, growth and survival of L. monocytogenes on food is tested using inoculation densities ranging from less than 10 2 to over 10 5  CFU g -1 . Inoculation densities on food have been rarely tested as a factor for growth. In this study, inoculation densities from 10 2 to 10 5 of L. monocytogenes were tested on iceberg lettuce (Lactuca sativa) in modified atmospheres and air in model packages at 4 and 8 °C to identify any potential inoculation density effects. On days 0, 2, 5 and 7, L. monocytogenes was extracted from the lettuce surface and enumerated via selective media. The resulting growth curves identified a significant inoculation density effect at 4 and 8 °C with significantly higher amounts of growth (1-2 logs) when lettuce was inoculated at 10 2  CFU g -1 as opposed to 10 4 and 10 5  CFU g -1 . In contrast, the use of different atmospheres had limited influence on growth of L. monocytogenes. In conclusion, greater emphasis on inoculation density of L. monocytogenes should be taken in inoculation experiments when confirmation of growth or the efficacies of growth inhibiting treatments are tested on ready-to-eat food such as lettuce.

Implementation of aerosol-cloud interactions in the regional atmosphere-aerosol model COSMO-MUSCAT(5.0) and evaluation using satellite data

NASA Astrophysics Data System (ADS)

Dipu, Sudhakar; Quaas, Johannes; Wolke, Ralf; Stoll, Jens; Mühlbauer, Andreas; Sourdeval, Odran; Salzmann, Marc; Heinold, Bernd; Tegen, Ina

2017-06-01

The regional atmospheric model Consortium for Small-scale Modeling (COSMO) coupled to the Multi-Scale Chemistry Aerosol Transport model (MUSCAT) is extended in this work to represent aerosol-cloud interactions. Previously, only one-way interactions (scavenging of aerosol and in-cloud chemistry) and aerosol-radiation interactions were included in this model. The new version allows for a microphysical aerosol effect on clouds. For this, we use the optional two-moment cloud microphysical scheme in COSMO and the online-computed aerosol information for cloud condensation nuclei concentrations (Cccn), replacing the constant Cccn profile. In the radiation scheme, we have implemented a droplet-size-dependent cloud optical depth, allowing now for aerosol-cloud-radiation interactions. To evaluate the models with satellite data, the Cloud Feedback Model Intercomparison Project Observation Simulator Package (COSP) has been implemented. A case study has been carried out to understand the effects of the modifications, where the modified modeling system is applied over the European domain with a horizontal resolution of 0.25° × 0.25°. To reduce the complexity in aerosol-cloud interactions, only warm-phase clouds are considered. We found that the online-coupled aerosol introduces significant changes for some cloud microphysical properties. The cloud effective radius shows an increase of 9.5 %, and the cloud droplet number concentration is reduced by 21.5 %.

DNA packaging and ejection forces in bacteriophage

PubMed Central

Kindt, James; Tzlil, Shelly; Ben-Shaul, Avinoam; Gelbart, William M.

2001-01-01

We calculate the forces required to package (or, equivalently, acting to eject) DNA into (from) a bacteriophage capsid, as a function of the loaded (ejected) length, under conditions for which the DNA is either self-repelling or self-attracting. Through computer simulation and analytical theory, we find the loading force to increase more than 10-fold (to tens of piconewtons) during the final third of the loading process; correspondingly, the internal pressure drops 10-fold to a few atmospheres (matching the osmotic pressure in the cell) upon ejection of just a small fraction of the phage genome. We also determine an evolution of the arrangement of packaged DNA from toroidal to spool-like structures. PMID:11707588

Monte Carlo calculation of the atmospheric antinucleon flux

NASA Astrophysics Data System (ADS)

Djemil, T.; Attallah, R.; Capdevielle, J. N.

2009-12-01

The atmospheric antiproton and antineutron energy spectra are calculated at float altitude using the CORSIKA package in a three-dimensional Monte Carlo simulation. The hadronic interaction is treated by the FLUKA code below 80 GeV/nucleon and NEXUS elsewhere. The solar modulation which is described by the force field theory and the geomagnetic effects are taken into account. The numerical results are compared with the BESS-2001 experimental data.

Packaging of MEMS/MOEMS and nanodevices: reliability, testing, and characterization aspects

NASA Astrophysics Data System (ADS)

Tekin, Tolga; Ngo, Ha-Duong; Wittler, Olaf; Bouhlal, Bouchaib; Lang, Klaus-Dieter

2011-02-01

The last decade witnessed an explosive growth in research and development efforts devoted to MEMS devices and packaging. The successfully developed MEMS devices are, for example inkjet, pressure sensors, silicon microphones, accelerometers, gyroscopes, MOEMS, micro fuel cells and emerging MEMS. For the next decade, MEMS/MOEMS and nanodevice based products will penetrate into IT, telecommunications, automotive, defense, life sciences, medical and implantable applications. Forecasts say the MEMS market to be $14 billion by 2012. The packaging cost of MEMS/MOEMS products in general is about 70 percent. Unlike today's electronics IC packaging, their packaging are custom-built and difficult due to the moving structural elements. In order for the moving elements of a MEMS device to move effectively in a well-controlled atmosphere, hermetic sealing of the MEMS device in a cap is necessary. For some MEMS devices, such as resonators and gyroscopes, vacuum packaging is required. Usually, the cap is processed at the wafer level, and thus MEMS packaging is truly a wafer level packaging. In terms of MEMS/MOEMS and nanodevice packaging, there are still many critical issues need to be addressed due to the increasing integration density supported by 3D heterogeneous integration of multi-physic components/layers consisting of photonics, electronics, rf, plasmonics, and wireless. The infrastructure of MEMS/MOEMS and nanodevices and their packaging is not well established yet. Generic packaging platform technologies are not available. Some of critical issues have been studied intensively in the last years. In this paper we will discuss about processes, reliability, testing and characterization of MEMS/MOEMS and nanodevice packaging.

ROLE OF CANOPY-SCALE PHOTOCHEMISTRY IN MODIFYING BIOGENIC-ATMOSPHERE EXCHANGE OF REACTIVE TERPENE SPECIES: RESULTS FROM THE CELTIC FIELD STUDY

EPA Science Inventory

A one-dimensional canopy model was used to quantify the impact of photochemistry in modifying biosphere-atmosphere exchange of trace gases. Canopy escape efficiencies, defined as the fraction of emission that escapes into the well-mixed boundary layer, were calculated for reactiv...

Survival of Aspergillus flavus and Fusarium moniliforme in High-Moisture Corn Stored Under Modified Atmospheres

PubMed Central

Wilson, David M.; Huang, L. H.; Jay, Edward

1975-01-01

Freshly harvested high-moisture corn with 29.4% moisture and corn remoistened to 19.6% moisture were inoculated with Aspergillus flavus Link ex Fr. and stored for 4 weeks at about 27 C in air (0.03% CO2, 21% O2, and 78% N2) and three modified atmospheres: (i) 99.7% N2 and 0.3% O2; (ii) 61.7% CO2, 8.7% O2, and 29.6% N2; and (iii) 13.5% CO2, 0.5% O2, and 84.8% N2. Kernel infections by A. flavus, Fusarium moniliforme (Sheld.) Snyd. et Hans., and other fungi were monitored weekly. The modified-atmosphere treatments delayed deterioration by A. flavus and F. moniliforme, but their growth was not completely stopped. A. flavus survived better in the remoistened than in the freshly harvested corn. F. moniliforme survived in both. A. flavus and F. moniliforme were the dominant fungi in corn removed from the modified atmospheres and exposed to normal air for 1 week. PMID:811165

MORTICIA, a statistical analysis software package for determining optical surveillance system effectiveness.

NASA Astrophysics Data System (ADS)

Ramkilowan, A.; Griffith, D. J.

2017-10-01

Surveillance modelling in terms of the standard Detect, Recognise and Identify (DRI) thresholds remains a key requirement for determining the effectiveness of surveillance sensors. With readily available computational resources it has become feasible to perform statistically representative evaluations of the effectiveness of these sensors. A new capability for performing this Monte-Carlo type analysis is demonstrated in the MORTICIA (Monte- Carlo Optical Rendering for Theatre Investigations of Capability under the Influence of the Atmosphere) software package developed at the Council for Scientific and Industrial Research (CSIR). This first generation, python-based open-source integrated software package, currently in the alpha stage of development aims to provide all the functionality required to perform statistical investigations of the effectiveness of optical surveillance systems in specific or generic deployment theatres. This includes modelling of the mathematical and physical processes that govern amongst other components of a surveillance system; a sensor's detector and optical components, a target and its background as well as the intervening atmospheric influences. In this paper we discuss integral aspects of the bespoke framework that are critical to the longevity of all subsequent modelling efforts. Additionally, some preliminary results are presented.

Code Development in Coupled PARCS/RELAP5 for Supercritical Water Reactor

DOE PAGES

Hu, Po; Wilson, Paul

2014-01-01

The new capability is added to the existing coupled code package PARCS/RELAP5, in order to analyze SCWR design under supercritical pressure with the separated water coolant and moderator channels. This expansion is carried out on both codes. In PARCS, modification is focused on extending the water property tables to supercritical pressure, modifying the variable mapping input file and related code module for processing thermal-hydraulic information from separated coolant/moderator channels, and modifying neutronics feedback module to deal with the separated coolant/moderator channels. In RELAP5, modification is focused on incorporating more accurate water properties near SCWR operation/transient pressure and temperature in themore » code. Confirming tests of the modifications is presented and the major analyzing results from the extended codes package are summarized.« less

The abundance and diversity of antibiotic resistance genes in the atmospheric environment of composting plants.

PubMed

Gao, Min; Qiu, Tianlei; Sun, Yanmei; Wang, Xuming

2018-07-01

Composting is considered to reduce the introduction of antimicrobial resistance genes (ARGs) into the environment through land application of manure; however, the possible pollution of ARGs in the atmospheric environment of composting plants is unknown. In this study, 29 air samples including up- and downwind, composting, packaging, and office areas from 4 composting plants were collected. Dynamic concentrations of 22 subtypes of ARGs, class 1 integron (intl1), and 2 potential human pathogenic bacteria (HPB), and bacterial communities were investigated using droplet digital PCR and 16S rRNA gene sequencing, respectively. In this study, intl1 and 22 subtypes of ARGs (except tetQ) were detected in air of composting, packaging, office, and downwind areas. The highest concentration of 15 out of 22 subtypes of ARGs was detected in the packaging areas, and intl1 also had the maximum average concentration of 10 4  copies/m 3 , with up to (1.78 ± 0.49) × 10 -2 copies/16S rRNA copy. Non-metric multi-dimensional scaling of ARGs, potential HPBs, and bacterial components all indicated that the bioaerosol pollutant pattern in packaging areas was most similar to that in composting areas, followed by office, downwind, and upwind areas. The co-occurrence between ARGs and bacterial taxa assessed by Procrustes test, mantel test, and network analysis implied that aerosolized ARG fragments from composting and packaging areas contributed to the compositions of ARG aerosols in office and downwind areas. The results presented here show that atmoshperic environments of composting plants harbor abundant and diverse ARGs, which highlight the urgent need for comprehensive evaluation of potential human health and ecological risks of composts during both production as well as land application. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sensitivity of a cloud parameterization package in the National Center for Atmospheric Research Community Climate Model

NASA Astrophysics Data System (ADS)

Kao, C.-Y. J.; Smith, W. S.

1999-05-01

A physically based cloud parameterization package, which includes the Arakawa-Schubert (AS) scheme for subgrid-scale convective clouds and the Sundqvist (SUN) scheme for nonconvective grid-scale layered clouds (hereafter referred to as the SUNAS cloud package), is incorporated into the National Center for Atmospheric Research (NCAR) Community Climate Model, Version 2 (CCM2). The AS scheme is used for a more reasonable heating distribution due to convective clouds and their associated precipitation. The SUN scheme allows for the prognostic computation of cloud water so that the cloud optical properties are more physically determined for shortwave and longwave radiation calculations. In addition, the formation of anvil-like clouds from deep convective systems is able to be simulated with the SUNAS package. A 10-year simulation spanning the period from 1980 to 1989 is conducted, and the effect of the cloud package on the January climate is assessed by comparing it with various available data sets and the National Center for Environmental Protection/NCAR reanalysis. Strengths and deficiencies of both the SUN and AS methods are identified and discussed. The AS scheme improves some aspects of the model dynamics and precipitation, especially with respect to the Pacific North America (PNA) pattern. CCM2's tendency to produce a westward bias of the 500 mbar stationary wave (time-averaged zonal anomalies) in the PNA sector is remedied apparently because of a less "locked-in" heating pattern in the tropics. The additional degree of freedom added by the prognostic calculation of cloud water in the SUN scheme produces interesting results in the modeled cloud and radiation fields compared with data. In general, too little cloud water forms in the tropics, while excessive cloud cover and cloud liquid water are simulated in midlatitudes. This results in a somewhat degraded simulation of the radiation budget. The overall simulated precipitation by the SUNAS package is, however, substantially improved over the original CCM2.

Compact, Engineered, 2-Micron Coherent Doppler Wind Lidar Prototype for Field and Airborne Validation: Doppler Aerosol WiNd Lidar (DAWN). Interim Review #1 (6 months)

NASA Technical Reports Server (NTRS)

Kavaya, Michael J.; Singh, Upendra N.; Koch, Grady J.; Yu, Jirong; Amzajerdian, Farzin; Trieu, Bo C.; Petros, Mulugeta

2006-01-01

A new project, selected in 2005 by NASA's Science Mission Directorate (SMD), under the Instrument Incubator Program (IIP), will be described. The 3-year effort is intended to design, fabricate, and demonstrate a packaged, rugged, compact, space-qualifiable coherent Doppler wind lidar (DWL) transceiver capable of future validation in an aircraft and/or Unmanned Aerial Vehicle (UAV). The state-of-the-art 2-micron coherent DWL breadboard at NASA/LaRC will be engineered and compactly packaged consistent with future aircraft flights. The packaged transceiver will be integrated into a coherent DWL system test bed at LaRC. Atmospheric wind measurements will be made to validate the packaged technology. This will greatly advance the coherent part of the hybrid DWL solution to the need for global tropospheric wind measurements.

A System of Systems Approach for Martian Exploration

NASA Astrophysics Data System (ADS)

Semrud, E. B.; Evans, B. W.; Fredericks, B.; Wells, D.

2012-06-01

A system of systems is designed for characterization of the Martian atmosphere and exploration of lava tubes in preparation for human colonization. Multiple expendable deployable sensor packages ensure mission success with a high level of redundancy.

Modified technique for processing multiangle lidar data measured in clear and moderately polluted atmospheres

Treesearch

Vladimir Kovalev; Cyle Wold; Alexander Petkov; Wei Min Hao

2011-01-01

We present a modified technique for processing multiangle lidar data that is applicable for relatively clear atmospheres, where the utilization of the conventional Kano-Hamilton method meets significant issues. Our retrieval algorithm allows computing the two-way transmission and the corresponding extinction-coefficient profile in any slope direction searched during...

Thermal testing techniques for space shuttle thermal protection system panels

NASA Technical Reports Server (NTRS)

Cox, B. G.

1972-01-01

An experimental system was developed for evaluation of the effects of aerodynamic heating and cooling, vacuum, and pressure loading on candidate insulation packages proposed for use on the space shuttle. The system includes a number of design features which facilitate rapid recycle times. This is necessary to efficiently conduct extensive thermal cycling tests on these insulation packages to determine their reuse capabilities. The heart of the system is a 26-inch graphite element radiant heater. A susceptor plate functions as a uniform-temperature intermediate radiating surface. The susceptor also forms the lid of an inert atmosphere enclosure which separates the heater from the oxidizing test atmosphere. In some tests the plate properly simulates the heating from an actual flight heat-shield panel. Although other materials were used at lower required test temperatures, 2500 F was routinely achieved using a coated columbium susceptor plate.

Atmospheric-Pressure Cold Plasmas Used to Embed Bioactive Compounds in Matrix Material for Active Packaging of Fruits and Vegetables

NASA Astrophysics Data System (ADS)

Fernandez, Sulmer; Pedrow, Patrick; Powers, Joseph; Pitts, Marvin

2009-10-01

Active thin film packaging is a technology with the potential to provide consumers with new fruit and vegetable products-if the film can be applied without deactivating bioactive compounds.Atmospheric pressure cold plasma (APCP) processing can be used to activate monomer with concomitant deposition of an organic plasma polymerized matrix material and to immobilize a bioactive compound all at or below room temperature.Aims of this work include: 1) immobilize an antimicrobial in the matrix; 2) determine if the antimicrobial retains its functionality and 3) optimize the reactor design.The plasma zone will be obtained by increasing the voltage on an electrode structure until the electric field in the feed material (argon + monomer) yields electron avalanches. Results will be described using Red Delicious apples.Prospective matrix precursors are vanillin and cinnamic acid.A prospective bioactive compound is benzoic acid.

Comparison of effects of copropagated and precomputed atmosphere profiles on Monte Carlo trajectory simulation

NASA Technical Reports Server (NTRS)

Queen, Eric M.; Omara, Thomas M.

1990-01-01

A realization of a stochastic atmosphere model for use in simulations is presented. The model provides pressure, density, temperature, and wind velocity as a function of latitude, longitude, and altitude, and is implemented in a three degree of freedom simulation package. This implementation is used in the Monte Carlo simulation of an aeroassisted orbital transfer maneuver and results are compared to those of a more traditional approach.

DART: Instrument Package Developed for Investigating Atmospheric Dust on Mars

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.

2001-01-01

Mars' dust-filled atmosphere could be a significant problem for photovoltaic array operation during long missions on the surface of Mars. Measurements made by Pathfinder showed a 0.3-percent loss of solar array performance per day due to dust obscuration. Thus, dust deposition is the limiting factor in the lifetime of solar arrays for Martian power systems, and developing design tools to mitigate this deposition is important for long missions.

Non-LTE model atmospheres for supersoft X-ray sources

NASA Astrophysics Data System (ADS)

Rauch, T.; Werner, K.

2010-02-01

In the last decade, X-ray observations of hot stellar objects became available with unprecedented resolution and S/N ratio. For an adequate interpretation, fully metal-line blanketed Non-LTE model-atmospheres are necessary. The Tübingen Non-LTE Model Atmosphere Package (TMAP) can calculate such model atmospheres at a high level of sophistication. Although TMAP is not especially designed for the calculation of spectral energy distributions (SEDs) at extreme photospheric parameters, it can be employed for the spectral analysis of burst spectra of novae like V4743 Sgr or line identifications in observations of neutron stars with low magnetic fields in low-mass X-ray binaries (LMXBs) like EXO 0748-676.

21 CFR 176.130 - Anti-offset substances.

Code of Federal Regulations, 2014 CFR

2014-04-01

... paperboard used for food packaging in accordance with the provisions of this section: (a) The substances are... Methyl hydrogen polysiloxanes Industrial starch—modified Complying with § 178.3520 of this chapter...

Computer assisted learning (CAL) of oral manifestations of HIV disease.

PubMed

Porter, S R; Telford, A; Chandler, K; Furber, S; Williams, J; Price, S; Scully, C; Triantos, D; Bain, L

1996-09-07

General dental practitioners (GDPs) in the UK may wish additional education on relevant aspects of human immunodeficiency virus (HIV) disease. The aim of the present study was to develop and assess a computer assisted learning package on the oral manifestations of HIV disease of relevance to GDPs. A package was developed using a commercially-available software development tool and assessed by a group of 75 GDPs interested in education and computers. Fifty-four (72%) of the GDPs completed a self-administered questionnaire of their opinions of the package. The majority reported the package to be easy to load and run, that it provided clear instructions and displays, and that it was a more effective educational tool than videotapes, audiotapes, professional journals and textbooks, and of similar benefit as post-graduate courses. The GDPs often commented favourably on the effectiveness of the clinical images and use of questions and answers, although some had criticisms of these and other aspects of the package. As a consequence of this investigation the package has been modified and distributed to GDPs in England and Wales.

Atmospheric science facility pallet-only mode space transportation system payload (feasibility study), Volume 1

NASA Technical Reports Server (NTRS)

1975-01-01

The economic and technical feasibility is assessed of employing a pallet-only mode for conducting Atmospheric Magnetospheric Plasmas-in-Space experiments. A baseline design incorporating the experiment and instrument descriptions is developed. The prime instruments are packaged into four pallets in a physical and functional manner compatible with the Space Transportation System capabilities and/or constraints and an orbiter seven-day mission timeline. Operational compatibility is verified between the orbiter/payload and supporting facilities. The development status and the schedule requirements applicable to the Atmospheric Science Facility mission are identified. Conclusions and recommendations are presented and discussed.

IONIZING RADIATION AND PACKAGING EFFECTS ON RESPIRATORY BEHAVIOR, FUNGAL GROWTH, AND STORAGE-LIFE OF PEACHES, PRUNUS PERSICA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dhaliwal, A.S.; Salunkhe, D.K.

1963-01-01

Investigations were conducted in 1960 to study effects of fast electron and gamma radiations and packaging films on respiratory rate, control of fungal deterioration, and subsequent refrigeration life of peaches. The fungi responsible for deterioration of peaches were also studied in vitro to determine if they were susceptible or resistant to ionizing (fast electron and gamma) radiations. Respiratory behavior of the fruits under normal as well as modified conditions was assessed with a Claypool and Keefer-type respirometer and Orsat- type gas analyzer. Two kinds of polyethylene films were used for packaging fruits. The fruits after treatments and packaging were storedmore » at 40 un. Concent 85% F and 85 per cent relative humidity and at 75 un. Concent 85% F and 35 per cent relative humidity. (auth)« less

Atmospheric oxygen and other conditions affecting the production of cereulide by Bacillus cereus in food.

PubMed

Jääskeläinen, E L; Häggblom, M M; Andersson, M A; Salkinoja-Salonen, M S

2004-10-01

Factors influencing the production of cereulide, the emetic toxin of Bacillus cereus in food and laboratory media were investigated, using liquid chromatography-ion trap mass spectrometry and sperm motility inhibition bioassay for detection and quantitation. Oxygen was essential for production of the emetic toxin by B. cereus. When beans, rice or tryptic soy broth were inoculated with cereulide producing strains B203, B116 (recent food isolates) or the strain F-4810/72, high amounts (2 to 7 microg ml(-1) or g(-1) wet wt) of cereulide accumulated during 4-day storage at room temperature. In parallel cultures and foods, stored under nitrogen atmosphere (> 99.5% N2), less than 0.05 microg of cereulide ml(-1) or g(-1) wet wt accumulated. The outcome of the bioassay matched that of the chemical assay, with no indication of interference by substances in the rice or beans. Boiling for 20 to 30 min did not inactivate cereulide or cereulide producing strains in rice or the beans. Adding l-leucine and l-valine (0.3 g l(-1)) stimulated cereulide production 10- to 20-fold in R2A and in rice water agar. When the B. cereus strains were grown on agar media under permissive conditions (air, room temperature), cereulide was produced overnight with little or no increase when the incubation was extended to 4 days. In broth culture, the production of cereulide started later than 16-24 h. Anoxic storage prevented cereulide production also when the amino acids had been supplied. Packaging with modified atmosphere low in oxygen may thus be used to reduce the risk of cereulide formation during storage of food. Copyright 2004 Elsevier B.V.

Chitosan boosts the antimicrobial activity of Origanum vulgare essential oil in modified atmosphere packaged pork.

PubMed

Paparella, Antonello; Mazzarrino, Giovanni; Chaves-López, Clemencia; Rossi, Chiara; Sacchetti, Giampiero; Guerrieri, Oana; Serio, Annalisa

2016-10-01

The potential of chitosan as a possible booster of the antimicrobial activity of Origanum vulgare EO (OEO) against spoilage bacteria and Listeria monocytogenes was investigated in fresh pork meat. Pork fillets were inoculated with 3 L. monocytogenes strains, dipped either in Origanum vulgare (oregano) Essential Oil (OEO) at 2 and 4%, or in chitosan 1% alone or added with 2 and 4% OEO, then packed under modified atmosphere (70% O2, 20% CO2, 10% N2) and stored at 4 °C for 15 days. OEO did not reduce L. monocytogenes growth, while 2 Log decrease was obtained after 2 days of storage in treatments with chitosan alone or with OEO, with growth inhibition up to day 15 in samples with chitosan and OEO 4%. When OEO was combined with chitosan, total viable counts and spoilage bacteria were reduced and contained over time, particularly Pseudomonas (2.0 Log CFU/g at day 15) and Brochothrix thermosphacta (undetectable). All the treatments applied extended meat shelf-life with respect to control, whose commercial shelf-life was 10 days. Chitosan treatments enhanced L* and maintained a* values almost stable during storage. Chitosan and OEO singly applied reduced lipid oxidation (0.62-0.75 mg malondialdehyde/Kg meat) compared to control (0.99 mg malondialdehyde/Kg meat). Finally, chitosan treated samples were not recognized with respect to the control, whereas OEO gave bitter taste; chitosan with OEO instead mitigated the effect of OEO addition to meat. Chitosan combined with OEO boosts its antimicrobial activity and shows a potential for application in industrial production of fresh pork in MAP, to achieve shelf-life extension, control of L. monocytogenes growth, stability of color and protective effect from oxidation, with low sensory impact. Copyright © 2016 Elsevier Ltd. All rights reserved.