Science.gov

Sample records for bread spoilage fungi

  1. Study of kefir grains application in sourdough bread regarding rope spoilage caused by Bacillus spp.

    PubMed

    Mantzourani, I; Plessas, S; Saxami, G; Alexopoulos, A; Galanis, A; Bezirtzoglou, E

    2014-01-15

    Sourdough breads prepared with kefir grains resulted in appearance of rope spoilage at the 15th day of bread storage, while the control samples (sourdough breads prepared with wild microflora) were spoiled approximately at the 7th day. Denaturing Gradient Gel Electrophoresis (DGGE) analysis confirmed the above macroscopic observation since Bacillus spp. were detected on sourdough breads prepared with kefir grains at the 15th day of bread storage. The content of organic acids that play synergistic role regarding the enhancement of bread self life was also determined. Lactic acid concentration of sourdough breads prepared with kefir grains were approximately 41-82% higher than the control samples, while acetic acid concentration was about 0.5-1-fold higher respectively. The concentration of some other organic acids studied was also found in higher levels (up to 0.06μg/g) than the control samples. These findings could probably explain the stability of breads prepared with kefir grains against rope spoilage.

  2. Mould spoilage of bread and its biopreservation: A review of current strategies for bread shelf life extension.

    PubMed

    Axel, Claudia; Zannini, Emanuele; Arendt, Elke K

    2016-03-15

    Microbial spoilage of bread and the consequent waste problem causes large economic losses for both the bakery industry and the consumer. Furthermore the presence of mycotoxins due to fungal contamination in cereals and cereal products remains a significant issue. The use of conventional chemical preservatives has several drawbacks, necessitating the development of clean-label alternatives. In this review, we describe current research aiming to extend the shelf life of bread through the use of more consumer friendly and ecologically sustainable preservation techniques as alternatives to chemical additives. Studies on the in situ-production/-expression of antifungal compounds are presented, with special attention given to recent developments over the past decade. Sourdough fermented with antifungal strains of lactic acid bacteria is an area of increasing focus and serves as a high-potential biological ingredient to produce gluten-containing and gluten-free breads with improved nutritional value, quality and safety due to shelf-life extension, and is in-line with consumer's demands for more products containing less additives. Other alternative biopreservation techniques include the utilization of antifungal peptides, ethanol and plant extracts. These can be added to bread formulations or incorporated in antimicrobial films for active packaging of bread. This review outlines recent progress that has been made in the area of bread biopreservation and future perspectives in this important area.

  3. Diversity of spoilage fungi associated with various French dairy products.

    PubMed

    Garnier, Lucille; Valence, Florence; Pawtowski, Audrey; Auhustsinava-Galerne, Lizaveta; Frotté, Nicolas; Baroncelli, Riccardo; Deniel, Franck; Coton, Emmanuel; Mounier, Jérôme

    2017-01-16

    Yeasts and molds are responsible for dairy product spoilage, resulting in significant food waste and economic losses. Yet, few studies have investigated the diversity of spoilage fungi encountered in dairy products. In the present study, 175 isolates corresponding to 105 from various spoiled dairy products and 70 originating from dairy production environments, were identified using sequencing of the ITS region, the partial β-tubulin, calmodulin and/or EFα genes, and the D1-D2 domain of the 26S rRNA gene for filamentous fungi and yeasts, respectively. Among the 41 species found in spoiled products, Penicillium commune and Penicillium bialowiezense were the most common filamentous fungi, representing around 10% each of total isolates while Meyerozyma guilliermondii and Trichosporon asahii were the most common yeasts (4.8% each of total isolates). Several species (e.g. Penicillium antarcticum, Penicillium salamii and Cladosporium phyllophilum) were identified for the first time in dairy products or their environment. In addition, numerous species were identified in both spoiled products and their corresponding dairy production environment suggesting that the latter acts as a primary source of contamination. Secondly, the resistance to chemical preservatives (sodium benzoate, calcium propionate, potassium sorbate and natamycin) of 10 fungal isolates representative of the observed biodiversity was also evaluated. Independently of the fungal species, natamycin had the lowest minimum inhibitory concentration (expressed in gram of preservative/l), followed by potassium sorbate, sodium benzoate and calcium propionate. In the tested conditions, Cladosporium halotolerans and Didymella pinodella were the most sensitive fungi while Yarrowia lipolytica and Candida parapsilosis were the most resistant towards the tested preservatives. This study provides interesting information on the occurrence of fungal contaminants in dairy products and environments that may help developing

  4. Spoilage fungi and their mycotoxins in commercially marketed chestnuts.

    PubMed

    Overy, David P; Seifert, Keith A; Savard, Marc E; Frisvad, Jens C

    2003-11-15

    A nationwide survey was carried out to assess mould spoilage of Castanea sativa nuts sold in Canadian grocery stores in 1998-99. Morphological and cultural characters, along with secondary metabolite profiles derived from thin-layer chromatography, were used to sort and identify fungi cultured from nut tissue. Three mycotoxigenic fungi dominated (Penicillium crustosum, Penicillium glabrum/spinulosum and Penicillium discolor) and were isolated at frequencies of 67.1%, 18.6% and 17.7%, respectively, from a total sample size of 350 nuts. Another mycotoxin producer, Aspergillus ochraceus was also isolated, but at a much lower frequency. HPLC and diode array detection were used to confirm the suspected presence of the mycotoxins penitrem A, chaetoglobosin A and C, emodin and ochratoxin A in extracts prepared from naturally infected nut tissue. To the best of our knowledge, this is the first time emodin has been found in a naturally contaminated food source.

  5. Comparison of three Bacillus amyloliquefaciens strains growth behaviour and evaluation of the spoilage risk during bread shelf-life.

    PubMed

    Valerio, F; Di Biase, M; Huchet, V; Desriac, N; Lonigro, S L; Lavermicocca, P; Sohier, D; Postollec, F

    2015-02-01

    This study aims at the characterisation of growth behaviour of three strains of Bacillus amyloliquefaciens, isolated from ropy bread (ATCC8473), wheat grain (ISPA-S109.3) and semolina (ISPA-N9.1) to estimate rope spoilage risk in pan bread during shelf-life using the Sym'Previus tool. Cardinal values and growth/no growth boundaries were determined in broth, while artificial spore inoculations were performed in dough for various pan bread recipes to compare experimental counts with in silico growth simulations. Finally, two storage scenarios were tested to determine the probability to reach a spoilage threshold during bread shelf-life. Similarly to the safety criteria fixed for Listeria monocytogenes contamination in foodstuff complying with EC regulation, a potential rope spoilage threshold was arbitrary fixed at 5 log CFU/g for B. amyloliquefaciens. This study further underlines a higher rope spoilage potential of the ISPA strains as compared to the ATCC strain, thus emphasizing the interest to characterise both wild strains and reference strain to account for biological variability. In conclusion, this study showed that available decision making tools which are largely recognized to predict behaviour of pathogenic strains, shall also be used with spoilage strains to help maintain food quality and extend shelf-life.

  6. Effect of weak acid preservatives on growth of bakery product spoilage fungi at different water activities and pH values.

    PubMed

    Suhr, K I; Nielsen, P V

    2004-08-15

    Inhibition of spoilage organisms from bakery products by weak acid preservatives in concentrations of 0%, 0.003%, 0.03% and 0.3% (w/v) was investigated experimentally on a substrate media with water activity (a(w)) and pH ranging from sourdough-fermented acidic rye bread to alkaline intermediate moisture sponge cake types (a(w) 0.80-0.95, pH 4.7-7.4). Initially, rye bread conditions (a(w) 0.94-0.97 and pH 4.4-4.8) in combination with calcium propionate were investigated. Results showed that the highest concentration of propionate (0.3%) at all conditions apart from high a(w) (0.97) and high pH (4.8) totally inhibited fungal growth for a 2-week period, with the exception of Penicillium roqueforti, Penicillium commune and Eurotium rubrum. Characteristically for the major spoiler of rye bread, P. roqueforti, all three isolates tested were stimulated by propionate and the stimulation was significantly enhanced at high water activity levels. The effect of propionate on production of secondary metabolites (mycophenolic acid, rugulovasine, echinulin, flavoglaucin) was also studied, and variable or isolate dependent results were found. Subsequently, a screening experiment representing a wider range of bakery products was conducted using calcium propionate, potassium sorbate and sodium benzoate. The obtained data was modelled using survival analysis to determine 'spoilage-free time' for the fungi. At the low a(w) level (0.80) only Eurotium species grew within the test period of 30 days. Higher water activity levels as well as higher pH values decreased spoilage-free times of the fungi. The preservative calcium propionate was less effective than potassium sorbate and sodium benzoate.

  7. Fungicide contamination reduces beneficial fungi in bee bread based on an area-wide field study in honey bee, Apis mellifera, colonies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fermentation by fungi converts stored pollen into bee bread that is fed to and eaten by honey bee larvae, Apis mellifera. To explore the relationship between fungicide spraying and bee bread fungi, samples of bee bread collected from bee colonies pollinating orchards from seven locations over two y...

  8. Fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungi are seldom encountered in the archaeological record of foodstuffs but there are exceptions, especially for yeast. Excavated vessels contained identifiable residues of fermented beverages. Ancient ovens allow inferences on leavened breads. Mesopotamian clay tablets contain references to truffle...

  9. Differences Among Commonly Sprayed Orchard Fungicides in Targeting the Beneficial Fungi Associated with Honey Bee Colony and Bee Bread Provisions (In Vitro)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our studies evaluated the effects of representative fungicides, boscalid and pyraclostrobin, propiconazole, and chlorothalonil, alone and in combination, on 12 fungi species isolated from bee bread. Chlorothalonil was fungicidal (slowed growth without killing) and was least effective on Aspergillus...

  10. Impact of Orchard Fungicide Spraying on Lowering the Amount of Symbiotic Fungi in Bee Bread and Its Implications for Reduced Colony Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bee larvae depend on fungi to produce food (bee bread) from stored pollen as a developmental requirement. In the absence of or lower amounts of such fungi, chalkbrood disease (Ascosphaera apis) occurs, which is the highlight observation and the purpose for this chapter. Beebread is a competitive e...

  11. Fungicide contamination reduces beneficial fungi in bee bread based on an area-wide field study in honey bee, Apis mellifera, colonies.

    PubMed

    Yoder, Jay A; Jajack, Andrew J; Rosselot, Andrew E; Smith, Terrance J; Yerke, Mary Clare; Sammataro, Diana

    2013-01-01

    Fermentation by fungi converts stored pollen into bee bread that is fed to honey bee larvae, Apis mellifera, so the diversity of fungi in bee bread may be related to its food value. To explore the relationship between fungicide exposure and bee bread fungi, samples of bee bread collected from bee colonies pollinating orchards from 7 locations over 2 years were analyzed for fungicide residues and fungus composition. There were detectable levels of fungicides from regions that were sprayed before bloom. An organic orchard had the highest quantity and variety of fungicides, likely due to the presence of treated orchards within bees' flight range. Aspergillus, Penicillium, Rhizopus, and Cladosporium (beneficial fungi) were the primary fungal isolates found, regardless of habitat differences. There was some variation in fungal components amongst colonies, even within the same apiary. The variable components were Absidia, Alternaria, Aureobasidium, Bipolaris, Fusarium, Geotrichum, Mucor, Nigrospora, Paecilomyces, Scopulariopsis, and Trichoderma. The number of fungal isolates was reduced as an effect of fungicide contamination. Aspergillus abundance was particularly affected by increased fungicide levels, as indicated by Simpson's diversity index. Bee bread showing fungicide contamination originated from colonies, many of which showed chalkbrood symptoms.

  12. Stereo and scanning electron microscopy of in-shell Brazil nut (Bertholletia excelsa H.B.K.): part two-surface sound nut fungi spoilage susceptibility.

    PubMed

    Scussel, Vildes M; Manfio, Daniel; Savi, Geovana D; Moecke, Elisa H S

    2014-11-01

    This work reports the in-shell Brazil nut spoilage susceptible morpho-histological characteristics and fungi infection (shell, edible part, and brown skin) through stereo and scanning electron microscopies (SEM). The following characteristics related to shell (a) morphology-that allow fungi and insects' entrance to inner nut, and (b) histology-that allow humidity absorption, improving environment conditions for living organisms development, were identified. (a.1) locule in testae-the nut navel, which is a cavity formed during nut detaching from pods (located at 1.0 to 2.0/4th of the shell B&C nut faces linkage). It allows the nut brown skin (between shell and edible part) first contact to the external environment, through the (a.2) nut channel-the locule prolongation path, which has the water/nutrients cambium function for their transport and distribution to the inner seed (while still on the tree/pod). Both, locule followed by the channel, are the main natural entrance of living organisms (fungi and insects), including moisture to the inner seed structures. In addition, the (a.3) nut shell surface-which has a crinkled and uneven surface morphology-allows water absorption, thus adding to the deterioration processes too. The main shell histological characteristic, which also allows water absorption (thus improving environment conditions for fungi proliferation), is the (b.1) cell wall porosity-the multilayered wall and porous rich cells that compose the shell faces double tissue layers and the (b.2) soft tissue-the mix of tissues 2 faces corner/linkage. This work also shows in details the SEM nut spoilage susceptible features highly fungi infected with hyphae and reproductive structures distribution.

  13. Antifungal properties of gliadin films incorporating cinnamaldehyde and application in active food packaging of bread and cheese spread foodstuffs.

    PubMed

    Balaguer, Mari Pau; Lopez-Carballo, Gracia; Catala, Ramon; Gavara, Rafael; Hernandez-Munoz, Pilar

    2013-09-16

    Gliadin films incorporating 1.5, 3 and 5% cinnamaldehyde (g/100g protein) were tested against food-spoilage fungi Penicillium expansum and Aspergillus niger in vitro, and were employed in an active food packaging system for sliced bread and cheese spread. Gliadin films incorporating cinnamaldehyde were highly effective against fungal growth. P. expansum and A. niger were completely inhibited after storage in vitro for 10 days in the presence of films incorporating 3% cinnamaldehyde. Indeed 1.5% cinnamaldehyde was sufficient in the case of P. expansum. The amount of cinnamaldehyde retained in films after storage for 45 days at 20 °C and 0% RH was also sufficient in most cases to prevent fungal growth in vitro. Active food packaging with gliadin films incorporating 5% cinnamaldehyde increased the shelf-life of both sliced bread and cheese spread. Mold growth was observed on sliced bread after 27 days of storage at 23 °C with active packaging, whereas in the control bread packaged without the active film fungal growth appeared around the fourth day. In the cheese spread, no fungi were observed after 26 days of storage at 4 °C when the product was packaged with the active film. However, growth of fungi was observed in control packaged cheese after 16 days of storage. This work demonstrates a noteworthy potential of these novel bioplastics incorporating natural antimicrobial compounds as innovative solutions to be used in active food packaging to extend shelf-life of food products.

  14. Potential of Lactobacillus reuteri from Spontaneous 
Sourdough as a Starter Additive for Improving Quality Parameters of Bread

    PubMed Central

    Vaičiulytė-Funk, Lina; Šalomskienė, Joana; Alenčikienė, Gitana; Mieželienė, Aldona

    2016-01-01

    Summary Retardation of microbial spoilage of bread can be achieved by the use of spontaneous sourdough with an antimicrobial activity. This study was undertaken to identify lactic acid bacteria naturally occurring in spontaneous sourdough and use them for quality improvement and prolonging shelf life of rye, wheat and rye with wheat bread. Identification of isolates from spontaneous sourdough by pyrosequencing assay showed that Lactobacillus reuteri were dominant lactic acid bacteria. The isolates showed a wide range of antimicrobial activity and displayed a synergistic activity against other lactobacilli, some lactococci and foodborne yeasts. The best application of spontaneous sourdough was noticed in the rye bread with the lowest crumb firmness of the final product, although the sensory results of wheat and rye with wheat bread did not statistically differ from control bread. L. reuteri showed a high preserving capacity against fungi during storage. This may be due to bacteriocins and various fatty acids secreted into the growth medium that were identified by agar well diffusion assay and gas chromatography. L. reuteri showing high antimicrobial activity have the potential to be used as a starter additive that could improve safety and/or shelf life of bread. PMID:27956866

  15. Low Water Activity Packaged White Bread.

    DTIC Science & Technology

    1985-12-31

    Penicillium expansum , Aspergillus niger, and Clostridium sporogenes cultures were obtained from the cultL-e col tHon of the Department of Food Science...mcrobial spoilage. Therefore, a series of studies were conducted to challenge the bread with Penicillium expansum , Aspergillus niger, Clostridium sporogenes... Penicillium expansum and Aspergillus niger did not grow in the humectant breads containing 5% sorbitol, 2% propylene glycol and 2% glycerol (5-2-2) when

  16. Fractal Bread.

    ERIC Educational Resources Information Center

    Esbenshade, Donald H., Jr.

    1991-01-01

    Develops the idea of fractals through a laboratory activity that calculates the fractal dimension of ordinary white bread. Extends use of the fractal dimension to compare other complex structures as other breads and sponges. (MDH)

  17. Inhibition of fungal growth on bread by volatile components from spices and herbs, and the possible application in active packaging, with special emphasis on mustard essential oil.

    PubMed

    Nielsen, P V; Rios, R

    2000-09-25

    The effect of modified atmosphere packaging (MAP) on the most important spoilage fungi of bread was investigated. Penicillium commune, P. roqueforti, Aspergillus flavus and Endomyces fibuliger were able to grow at oxygen levels down to 0.03%, while the chalk mould E. fibuliger was capable of growing even in the presence of an oxygen absorber. High levels of carbon dioxide retarded growth but not completely. As an alternative to MAP active packaging (AP) using volatile essential oils (EO) and oleoresins (OL) from spices and herbs were tested against a range of fungi commonly found on bread. Concentrations of 1, 10 or 100 microl EO or OL were added to a filter paper placed in the lid of a Petri dish inoculated with one of the test fungi. The Petri dish was sealed hermetically to avoid the exchange of gases. Mustard essential oil showed the strongest effect. Cinnamon, garlic and clove also had high activity, while oregano oleoresin only inhibited growth weakly. Vanilla showed no inhibitory effect towards the tested microorganisms at the applied concentrations. A. flavus was more resistant than the other microorganisms while P. roqueforti was the most sensitive. Mustard essential oil was investigated in greater detail. The minimal inhibitory concentration (MIC) for the active component, allyl isothiocyanate (AITC), was determined for the same species and an additional three moulds and one yeast. MIC values ranged from 1.8 to 3.5 microg/ml gas phase. Results showed that whether AITC was fungistatic or fungicidal depended on its concentration, and the concentration of spores. When the gas phase contained at least 3.5 microg/ml, AITC was fungicidal to all tested fungi. Results of sensory evaluation showed, that hot-dog bread was more sensitive to AITC than rye bread. The minimal recognisable concentration of AITC was 2.4 microg/ml gas phase for rye bread and between 1.8 and 3.5 microg/ml gas phase for hot-dog bread. These findings showed that the required shelf-life of

  18. Spoilage of fruit juices by filamentous fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Contamination of molds in fruit juices has risen in recent years. Even though there are many critical control points in the processing protocols that are noted and maintained, there remains a problem with dairy and juices packed in paperboard cartons. This talk discusses the work involved in the dis...

  19. Post harvest spoilage of sweetpotato in tropics and control measures.

    PubMed

    Ray, R C; Ravi, V

    2005-01-01

    Sweetpotato storage roots are subjected to several forms of post harvest spoilage in the tropical climate during transportation from farmers' field to market and in storage. These are due to mechanical injury, weight loss, sprouting, and pests and diseases. Sweetpotato weevil is the single most important storage pest in tropical regions for which no control measures or resistant variety are yet available. Several microorganisms (mostly fungi) have been found to induce spoilage in stored sweetpotatoes. The most important among them are Botryodiplodia theobromae, Ceratocystis fimbriata, Fusarium spp., and Rhizopus oryzae. The other less frequently occurring spoilage microorganisms include Cochliobolus lunatus (Curvularia lunata), Macrophomina phaseolina, Sclerotium rolfsii, Rhizoctonia solani, Plenodomus destruens. Microbial spoilage of sweetpotato is found associated with decrease in starch, total sugar, organic acid (ascorbic acid and oxalic acid) contents with concomitant increase in polyphenols, ethylene, and in some instances phytoalexins. Several methods are used to control microbial spoilage. Curing to promote wound healing is found as the most suitable method to control microbial spoilage. Curing naturally occurs in tropical climates where mean day temperature during sweetpotato harvesting season (February-April) invariably remains at 32-35 degrees C and relative humidity at 80-95%. Sweetpotato varieties varied in their root dry matter content, and low root dry matter content attributed for their high curing efficiency. Curing efficiency of varieties also differed in response to curing periods. Fungicide treatment, bio-control, gamma irradiation, hydro warming, and storage in sand and saw dust were found to have intermediate impacts in controlling spoilage and enhancing shelf life of sweetpotato roots. Breeding program has to be chalked out to develop new varieties suitable to curing under tropical conditions in addition to developing varieties having multi

  20. Stability of sterigmatocystin during the bread making process and its occurrence in bread from the Latvian market.

    PubMed

    Veršilovskis, Aleksandrs; Bartkevičs, Vadims

    2012-05-01

    Sterigmatocystin (STC) is a carcinogenic and mutagenic mycotoxin produced by fungi of many Aspergillus species. The aim of this research was to test the stability of STC during the bread making process and to check bread samples from the Latvian market for STC contamination, using a previously developed electrospray positive ionisation (ESI(+)) liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Wheat grain naturally contaminated with STC was used for bread baking. STC was found to be stable during the bread-making process. In the food survey 17% of the analysed breads were positive for STC, with concentration levels of 2-7 μg kg(-1). One out of six rye bread samples, one out of nine rye-wheat bread samples and three out of 14 wheat bread samples were contaminated with STC. Four out of five contaminated samples contained whole grains as the main ingredient. We conclude that whole grain bread may be a possible source of STC, although even STC-positive bread samples identified in this study contained quite low toxin levels.

  1. Microbiological Spoilage of Cereal Products

    NASA Astrophysics Data System (ADS)

    Cook, Frederick K.; Johnson, Billie L.

    A wide range of cereal products, including bakery items, refrigerated dough, fresh pasta products, dried cereal products, snack foods, and bakery mixes, are manufactured for food consumption. These products are subject to physical, chemical, and microbiological spoilage that affects the taste, aroma, leavening, appearance, and overall quality of the end consumer product. Microorganisms are ubiquitous in nature and have the potential for causing food spoilage and foodborne disease. However, compared to other categories of food products, bakery products rarely cause food poisoning. The heat that is applied during baking or frying usually eliminates pathogenic and spoilage microorganisms, and low moisture contributes to product stability. Nevertheless, microbiological spoilage of these products occurs, resulting in substantial economic losses.

  2. Effects of bread making and wheat germ addition on the natural deoxynivalenol content in bread.

    PubMed

    Giménez, Isabel; Blesa, Jesús; Herrera, Marta; Ariño, Agustín

    2014-01-21

    Deoxynivalenol (DON, vomitoxin) is a type-B trichothecene mycotoxin produced by several field fungi such as Fusarium graminearum and Fusarium culmorum and known to have various toxic effects. This study investigated the effect of the bread making process on the stability of DON in common bread and wheat germ-enriched bread using naturally contaminated ingredients at the level of 560 µg/kg. The concentration of DON and its evolution during bread making were determined by immunoaffinity column cleanup followed by liquid chromatography with diode array detection (HPLC-DAD). During the bread making process, DON was reduced by 2.1% after fermentation and dropped by 7.1% after baking, reaching a maximum reduction of 19.8% in the crust as compared with a decrease of 5.6% in the crumb. The addition of 15% wheat germ to the dough did not affect DON stability during bread making, showing an apparent increase of 3.5% after fermentation and a reduction by 10.2% after baking.

  3. Rope-producing strains of Bacillus spp. from wheat bread and strategy for their control by lactic acid bacteria.

    PubMed

    Pepe, Olimpia; Blaiotta, Giuseppe; Moschetti, Giancarlo; Greco, Teresa; Villani, Francesco

    2003-04-01

    Two types of white wheat bread (high- and low-type loaves) were investigated for rope spoilage. Thirty of the 56 breads tested developed rope spoilage within 5 days; the high-type loaves were affected by rope spoilage more than the low-type loaves. Sixty-one Bacillus strains were isolated from ropy breads and were characterized on the basis of their phenotypic and genotypic traits. All of the isolates were identified as Bacillus subtilis by biochemical tests, but molecular assays (randomly amplified polymorphic DNA PCR assay, denaturing gradient gel electrophoresis analysis, and sequencing of the V3 region of 16S ribosomal DNA) revealed greater Bacillus species variety in ropy breads. In fact, besides strains of B. subtilis, Bacillus licheniformis, Bacillus cereus, and isolates of Bacillus clausii and Bacillus firmus were also identified. All of the ropy Bacillus isolates exhibited amylase activity, whereas only 32.4% of these isolates were able to produce ropiness in bread slices after treatment at 96 degrees C for 10 min. Strains of lactic acid bacteria previously isolated from sourdough were first selected for antirope activity on bread slices and then used as starters for bread-making experiments. Prevention of growth of approximately 10(4) rope-producing B. subtilis G1 spores per cm(2) on bread slices for more than 15 days was observed when heat-treated cultures of Lactobacillus plantarum E5 and Leuconostoc mesenteroides A27 were added. Growth of B. subtilis G1 occurred after 7 days in breads started with Saccharomyces cerevisiae T22, L. plantarum E5, and L. mesenteroides A27.

  4. Production of wheat bread without preservatives using sourdough starters

    PubMed Central

    Denkova, Rositsa; Ilieva, Svetla; Denkova, Zapryana; Georgieva, Ljubka; Yordanova, Mariya; Nikolova, Dilyana; Evstatieva, Yana

    2014-01-01

    In order for the beneficial effects of sourdough application in breadmaking to take place a proper selection of lactic acid bacteria species and strains, an appropriate technology and effective control of the purity and activity of the selected cultures. Four symbiotic starters for sourdough for the production of bread were developed and probated in a production laboratory using the selected strains Lactobacillus brevis LBRZ7, L. buchneri LBRZ6, L. plantarum X2, L. paracasei RN5, L. sanfranciscensis R and L. fermentum LBRH10 and the probiotic strain Propionibacterium freudenreichii ssp. shermanii NBIMCC 327. The starter sourdoughs that include Propionibacterium freudenreichii ssp. shermanii NBIMCC 327 had greater antimicrobial activity against saprophytic microorganisms: Bacillus subtilis, B. mesentericus, Aspergillus niger, Penicillium sp. and Rhizopus sp., but none of them inhibited the growth of bakery yeasts Saccharomyces cerevisiae. It was established that in order to prevent bacterial spoilage 10% of the selected starter sourdoughs had to be added in the breadmaking process, while for prevention of mold spoilage the necessary amount of starter sourdough had to be between 15% and 20%.The application of the developed starters for the production of wheat bread guarantees longer shelf life and no adverse alterations in the features of the final bread. PMID:26019574

  5. Production of wheat bread without preservatives using sourdough starters.

    PubMed

    Denkova, Rositsa; Ilieva, Svetla; Denkova, Zapryana; Georgieva, Ljubka; Yordanova, Mariya; Nikolova, Dilyana; Evstatieva, Yana

    2014-09-03

    In order for the beneficial effects of sourdough application in breadmaking to take place a proper selection of lactic acid bacteria species and strains, an appropriate technology and effective control of the purity and activity of the selected cultures. Four symbiotic starters for sourdough for the production of bread were developed and probated in a production laboratory using the selected strains Lactobacillus brevis LBRZ7, L. buchneri LBRZ6, L. plantarum X2, L. paracasei RN5, L. sanfranciscensis R and L. fermentum LBRH10 and the probiotic strain Propionibacterium freudenreichii ssp. shermanii NBIMCC 327. The starter sourdoughs that include Propionibacterium freudenreichii ssp. shermanii NBIMCC 327 had greater antimicrobial activity against saprophytic microorganisms: Bacillus subtilis, B. mesentericus, Aspergillus niger, Penicillium sp. and Rhizopus sp., but none of them inhibited the growth of bakery yeasts Saccharomyces cerevisiae. It was established that in order to prevent bacterial spoilage 10% of the selected starter sourdoughs had to be added in the breadmaking process, while for prevention of mold spoilage the necessary amount of starter sourdough had to be between 15% and 20%.The application of the developed starters for the production of wheat bread guarantees longer shelf life and no adverse alterations in the features of the final bread.

  6. Modeling food spoilage in microbial risk assessment.

    PubMed

    Koutsoumanis, Konstantinos

    2009-02-01

    In this study, I describe a systematic approach for modeling food spoilage in microbial risk assessment that is based on the incorporation of kinetic spoilage modeling in exposure assessment by combining data and models for the specific spoilage organisms (SSO: fraction of the total microflora responsible for spoilage) with those for pathogens. The structure of the approach is presented through an exposure assessment application for Escherichia coli O157:H7 in ground beef. The proposed approach allows for identifying spoiled products at the time of consumption by comparing the estimated level of SSO (pseudomonads) with the spoilage level (level of SSO at which spoilage is observed). The results of the application indicate that ignoring spoilage in risk assessment could lead to significant overestimations of risk.

  7. Breads of Native cultures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The sight and scent of a freshly baked loaf of bread has the romantic appeal that transcends all other culinary achievements of mankind! Bread, whether made of the flour of wheat, barley, rye, oats, millet, maize, sorghum, or rice, is a food enjoyed by people in all parts of the world. The virtually...

  8. Solving Microbial Spoilage Problems in Processed Foods

    NASA Astrophysics Data System (ADS)

    Clavero, Rocelle

    This chapter surveys common microbial food spoilage processes. The chapter is organized by food products and includes sections addressing spoilage in meat, poultry, fish; dairy products (milk, butter, cheese); beverage products; bakery products; canned foods; fruit and confectionery products; and emulsions. It addresses the isolation and identification of spoilage organisms and provides several case studies as examples. It introduces various organisms responsible for spoilage including Gram-positive lactic acid bacteria, Gram-negative aerobic bacteria, yeasts, molds, and fungal contaminants. Throughout the chapter, attention is given to when, where, and how spoilage organisms enter the food processing chain. Troubleshooting techniques are suggested. The effect (or lack of effect) of heating, dehydration, pH change, cooling, and sealing on various organisms is explained throughout. The chapter contains four tables that connect specific organisms to various spoilage manifestations in a variety of food products.

  9. Kefir immobilized on corn grains as biocatalyst for lactic acid fermentation and sourdough bread making.

    PubMed

    Plessas, Stavros; Alexopoulos, Athanasios; Bekatorou, Argyro; Bezirtzoglou, Eugenia

    2012-12-01

    The natural mixed culture kefir was immobilized on boiled corn grains to produce an efficient biocatalyst for lactic acid fermentation with direct applications in food production, such as sourdough bread making. The immobilized biocatalyst was initially evaluated for its efficiency for lactic acid production by fermentation of cheese whey at various temperatures. The immobilized cells increased the fermentation rate and enhanced lactic acid production compared to free kefir cells. Maximum lactic acid yield (68.8 g/100 g) and lactic acid productivity (12.6 g/L per day) were obtained during fermentation by immobilized cells at 37 °C. The immobilized biocatalyst was then assessed as culture for sourdough bread making. The produced sourdough breads had satisfactory specific loaf volumes and good sensory characteristics. Specifically, bread made by addition of 60% w/w sourdough containing kefir immobilized on corn was more resistant regarding mould spoilage (appearance during the 11(th) day), probably due to higher lactic acid produced (2.86 g/Kg of bread) compared to the control samples. The sourdough breads made with the immobilized biocatalyst had aroma profiles similar to that of the control samples as shown by headspace SPME GC-MS analysis.

  10. Inactivation of food spoilage fungi by ultra violet (UVC) irradiation.

    PubMed

    Begum, Mariam; Hocking, Ailsa D; Miskelly, Di

    2009-01-31

    The effect of ultraviolet irradiation (254 nm, UVC) on Aspergillus flavus, Aspergillus niger, Penicillium corylophilum and Eurotium rubrum was investigated using three different exposure techniques. Survival was determined for spores suspended in liquid medium after 1, 2 and 3 min UVC exposure at 4644 J/m(2)/min. The same UVC dose was applied to spores on the surface of agar plates for 5, 10, 15, 30, 60 and 120 s. Spores of A. niger were dried onto a membrane filter, then exposed to UVC treatment. In the liquid medium, treatments from 1-3 min significantly (P<0.001) reduce the number of viable spores. On the surface of agar plates, after a 15 s exposure, a 80-99% reduction of viable spores was observed for all species except A. niger, for which the reduction was only 62%. For spores dried onto filter membranes, a 3.5 log(10) reduction was achieved for A. niger after 180 s exposure. These observations suggest that UVC irradiation can effectively inactivate spores of A. flavus, P. corylophilum, E. rubrum and A. niger but the efficacy of UVC radiation against fungal spores varies significantly according to methods of exposure to the irradiation, and among genera.

  11. Consumer perception of bread quality.

    PubMed

    Gellynck, Xavier; Kühne, Bianka; Van Bockstaele, Filip; Van de Walle, Davy; Dewettinck, Koen

    2009-08-01

    Bread contains a wide range of important nutritional components which provide a positive effect on human health. However, the consumption of bread is declining during the last decades. This is due to factors such as changing eating patterns and an increasing choice of substitutes like breakfast cereals and fast foods. The aim of this study is to investigate consumer's quality perception of bread towards sensory, health and nutrition attributes. Four consumer segments are identified based on these attributes. The different consumer segments comprise consumers being positive to all three quality aspects of bread ("enthusiastic") as wells as consumers perceiving bread strongly as "tasteless", "non-nutritious" or "unhealthy". Moreover, factors are identified which influence the consumers' quality perception of bread. The results of our study may help health professionals and policy makers to systematically inform consumers about the positive effects of bread based on its components. Furthermore, firms can use the results to build up tailor-made marketing strategies.

  12. Microbiological Spoilage of Meat and Poultry Products

    NASA Astrophysics Data System (ADS)

    Cerveny, John; Meyer, Joseph D.; Hall, Paul A.

    Humankind has consumed animal protein since the dawn of its existence. The archaeological record shows evidence of animal protein consumption as early as 12,500 BC (Mann, 2005). Raw meat and poultry are highly perishable commodities subject to various types of spoilage depending on handling and storage conditions. Because of this high potential for spoilage, the historical record reveals that early civilizations used techniques such as salting, smoking, and drying to preserve meat (Mack, 2001; Bailey, 1986). Today, more than ever, because of the globalization of the food supply, and increasing demands from exacting consumers, the control of meat and poultry spoilage is essential.

  13. Quality of and mold growth on white enriched bread for military rations following directional microwave treatment.

    PubMed

    Lakins, D G; Echeverry, A; Alvarado, C Z; Brooks, J C; Brashears, M T; Brashears, M M

    2008-04-01

    Meals ready-to-eat (MRE) are self-contained and flexible packages used by military personnel while in the field to store food for an extended period of time; however, inclusion of white bread is not a common practice because of short shelf life stability and spoilage. The objective of this study was to determine mold inhibition and quality attributes over a 60-d period after applying directional microwaves. Different bread loaves were used for quality and for microbiological experiments. For microbiological analysis, bread was exposed to 0-, 5-, 6-, 7-, 8-, 9-, and 10-s directional microwave treatments after inoculation with a 3 strain cocktail of common bread mold, stored at 25 degrees C for 60 d, and monitored for mold growth. For quality analysis, bread was exposed to 0- and 10-s treatments, stored at 25 degrees C, and moisture, water activity (a(w)), softness, and sensory analysis were analyzed on 0, 7, 14, 28, 45, and 60 d. There was no quantifiable mold present at day 0 when treated for 10 s (P < 0.05). By day 60, the 10-s treatment had significantly lower counts (< 3 CFU/g) than the remaining treatments. Directional microwave treatment significantly decreased the moisture content of the bread but was not detectable by consumers. There was no difference in a(w) through day 45 but differences were detected at day 60. There were no differences in softness (mm) of the treated and untreated bread through day 60. No differences were detected by sensory analysis. Directional microwaves can be used to extend the shelf life of white enriched bread up 2 mo with minimal mold growth and without detrimental effect to quality.

  14. Bread Baking Contest.

    ERIC Educational Resources Information Center

    Blanchette, Amy; And Others

    1995-01-01

    Describes a classroom project in which elementary students bake homemade bread to learn about the settlement period in Canadian history and the early history of the students' community. Maintains that students learn to compare the lifestyle of the past with the present. (CFR)

  15. 9 CFR 319.880 - Breaded products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... CERTIFICATION DEFINITIONS AND STANDARDS OF IDENTITY OR COMPOSITION Miscellaneous § 319.880 Breaded products. The amount of batter and breading used as a coating for breaded product shall not exceed 30 percent of...

  16. 9 CFR 319.880 - Breaded products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... CERTIFICATION DEFINITIONS AND STANDARDS OF IDENTITY OR COMPOSITION Miscellaneous § 319.880 Breaded products. The amount of batter and breading used as a coating for breaded product shall not exceed 30 percent of...

  17. 9 CFR 319.880 - Breaded products.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CERTIFICATION DEFINITIONS AND STANDARDS OF IDENTITY OR COMPOSITION Miscellaneous § 319.880 Breaded products. The amount of batter and breading used as a coating for breaded product shall not exceed 30 percent of...

  18. A ready-to-use antifungal starter culture improves the shelf life of packaged bread.

    PubMed

    Gerez, C L; Torino, M I; Obregozo, M D; Font de Valdez, G

    2010-04-01

    Fungal spoilage is the main cause of economic loss in the baking industry. In this study, we developed a ready-to-use biopreserver (slurry [SL]) for nonsliced packed bread by using selected antifungal lactic acid bacteria (LAB) and low-cost ingredients that are compatible with the food matrix. Four LAB strains (Lactobacillus brevis CRL 772, L. brevis CRL 796, L. plantarum CRL 778, and L. reuteri CRL 1100) tested in bread preservation were able to inhibit Penicillium sp. growth and lengthen shelf life twofold with respect to breads prepared using only Saccharomyces cerevisiae (2 days shelf life). The best biopreservation effect (5 days shelf life) was obtained with 40% antifungal slurry SL778 containing L. plantarum CRL 778; this was as effective as 0.2% calcium propionate (PCa). The antifungal effect of SL778 was related to the synthesis of acetic and phenyllactic acid as well as lactic acid, which was produced at a high concentration (31.2 mmol/kg) and lowered the pH of the dough, favoring the undissociated fraction of the organic acids. The combination of the starter SL778 with 0.4% PCa extended the shelf life of packaged bread to 24 days, 2.6-fold longer than breads prepared with only 0.4% PCa.

  19. In situ control of food spoilage fungus using Lactobacillus acidophilus NCDC 291.

    PubMed

    Garcha, Seema; Natt, Navdeep Kaur

    2012-10-01

    A challenge for food industry today is to produce minimally processed food, without use of chemical preservatives and little compromise on nutritional status. Lactobacillus acidophilus NCDC 291 can be directly added to food where it enhances shelf life by competing with other microflora (both bacterial and fungal) for food and also by production of antimicrobial metabolites as bacteriocins. Comprehensive studies have demonstrated the in vitro activity of bacteriocins. However their role in preventing fresh food spoilage needs more elucidation. The present study was conducted to evaluate the efficacy of the whole cells of this organism as biopreservative agent against fungi. Four most commonly occurring spoilage fungi were isolated and were identified as Fusarium, Alternaria, Penicillium and Aspergillus. Growth of all of them was inhibited in in vitro studies, (approximately 33-43% decrease in mycelial dry weight basis between test and control). In situ biopreservation of Indian cheese and raw poultry meat was attempted and the colony count of Alternaria was significantly (p < 0.05, Bonferroni Holm) reduced in presence of L. acidophilus. Dip and Keep approach of preservation for Mangifera and Momordica were carried out in which microbial spoilage was not observed up to 6 days.

  20. Relationship between bread and obesity.

    PubMed

    Serra-Majem, Luis; Bautista-Castaño, Inmaculada

    2015-04-01

    Some studies have indicated that promoting the Mediterranean diet pattern as a model of healthy eating may help to prevent weight gain and the development of overweight/obesity. Bread consumption, which has been part of the traditional Mediterranean diet, has continued to decline in Spain and in the rest of the world, because the opinion of the general public is that bread fattens. The present study was conducted to assess whether or not eating patterns that include bread are associated with obesity and excess abdominal adiposity, both in the population at large or in subjects undergoing obesity management. The results of the present review indicate that reducing white bread, but not whole-grain bread, consumption within a Mediterranean-style food pattern setting is associated with lower gains in weight and abdominal fat. It appears that the different composition between whole-grain bread and white bread varies in its effect on body weight and abdominal fat. However, the term 'whole-grain bread' needs to be defined for use in epidemiological studies. Finally, additional studies employing traditional ways of bread production should analyse this effect on body-weight and metabolic regulation.

  1. Microbiological Spoilage of Canned Foods

    NASA Astrophysics Data System (ADS)

    Evancho, George M.; Tortorelli, Suzanne; Scott, Virginia N.

    Nicolas Appert (1749-1841) developed the first commercial process that kept foods from spoiling in response to an offer from the French government for a method of preserving food for use by the army and navy. Appert, a confectioner and chef, began to experiment in his workshop in Massy, near Paris, but since little was known about bacteriology and the causes of spoilage (Louis Pasteur had yet to formulate the germ theory), much of his work involved trial and error. In 1810, after years of experimenting, he was awarded the prize of 12,000 francs for his method of preservation, which involved cooking foods in sealed jars at high temperatures. He described his method of preserving food in a book published in 1811, "L'Art De Conserver, Pendant Plusiers Annes, Toutes les Substances Animales et Végétales," which translated means "The Art of Preserving All Kinds of Animal and Vegetable Substances for Several Years." He later built a bottling factory and began to produce preserved foods for the people of France and is credited with being the "Father of Canning."

  2. [Fungal spoilage of foods and its risk assessment].

    PubMed

    Udagawa, Shun-ichi

    2005-01-01

    From the second half of the 1990s, an increased regard has been given to the fungal spoilage of foods as follows: 1) post-harvest diseases and losses of fruits and vegetables, 2) deterioration of low water activity foods by xerophilic fungi, 3) contamination of psychrotolerant or psychrophilic fungi on foodstuffs and processed foods during storage and distribution at low temperature, and 4) spoilage of heat processed foods and soft drinks by heat-resistant fungi. In accordance with an international concern about food safety, mycotoxin contamination of foods has gained much global attention in recent times owing to its potential health hazards. The evaluation of mycotoxin hazards is principally based on the determination of a no-observed effect level (NOEL) in long-term toxicological studies, and the application of a safety factor (usually 100). In addition to hazard assessment, data on the natural occurrence of mycotoxins in various commodities and food intake data are needed to enable exposure assessment. Thus risk assessment of mycotoxins is, in fact, the product of hazard assessment and exposure assessment. In 1997, the FAO/WHO Joint Expert Committee on Food Additives (JECFA) considered estimates of the carcinogenic potency of aflatoxins and the potential risks associated with their intake. Recently the Codex Alimentarius Commission (Codex) has established standards for aflatoxin M1 in milk and for patulin in apple juice. The Codex is an international organization, supported by FAO/WHO, aiming at facilitating world trade and protecting the health of the consumer by developing international standards for food and feeds. Apart from aflatoxins, the JECFA has measured a provisional tolerable daily intake (TDI) for ochratoxin A, patulin, deoxynivalenol, T-2/HT-2 toxins, zearalenone and fumonisins. In 2001, the mycotoxins evaluated or re-evaluated at the JECFA meeting included ochratoxin A, deoxynivalenol, T-2/HT-2 toxins, fumonisins, and aflatoxin M1. In Japan

  3. Breaking the Bread of Life.

    ERIC Educational Resources Information Center

    Mineo, Thomas M.; Royce, Christine A.

    2000-01-01

    Describes Bishop Hannan High School's (Pennsylvania) retreat program, in which students learn to develop a spiritual element in their lives. Discusses the theme, "The Bread of Life," and how the process of baking bread for communion helped unite and nourish students. Reports that, through a variety of fellowship activities, students gained a sense…

  4. Undergraduate Laboratory Exercises Specific to Food Spoilage Microbiology

    ERIC Educational Resources Information Center

    Snyder, Abigail B.; Worobo, Randy W.; Orta-Ramirez, Alicia

    2016-01-01

    Food spoilage has an enormous economic impact, and microbial food spoilage plays a significant role in food waste and loss; subsequently, an equally significant portion of undergraduate food microbiology instruction should be dedicated to spoilage microbiology. Here, we describe a set of undergraduate microbiology laboratory exercises that focus…

  5. Can bread processing conditions alter glycaemic response?

    PubMed

    Lau, Evelyn; Soong, Yean Yean; Zhou, Weibiao; Henry, Jeyakumar

    2015-04-15

    Bread is a staple food that is traditionally made from wheat flour. This study aimed to compare the starch digestibility of western baked bread and oriental steamed bread. Four types of bread were prepared: western baked bread (WBB) and oriental steamed bread (OSB), modified baked bread (MBB) made with the OSB recipe and WBB processing, and modified steamed bread (MSB) made with the WBB recipe and OSB processing. MBB showed the highest starch digestibility in vitro, followed by WBB, OSB and MSB. A similar trend was observed for glycaemic response in vivo. MBB, WBB, OSB and MSB had a glycaemic index of 75±4, 71±5, 68±5 and 65±4, respectively. Processing differences had a more pronounced effect on starch digestibility in bread, and steamed bread was healthier in terms of glycaemic response. The manipulation of processing conditions could be an innovative route to alter the glycaemic response of carbohydrate-rich foods.

  6. Gamma radiation effects on commercial Mexican bread making wheat flour

    NASA Astrophysics Data System (ADS)

    Agúndez-Arvizu, Z.; Fernández-Ramírez, M. V.; Arce-Corrales, M. E.; Cruz-Zaragoza, E.; Meléndrez, R.; Chernov, V.; Barboza-Flores, M.

    2006-04-01

    Gamma irradiation is considered to be an alternative method for food preservation to prevent food spoilage, insect infestation and capable of reducing the microbial load. In the present investigation, commercial Mexican bread making wheat flour was irradiated at 1.0 kGy using a 60C Gammabeam 651 PT irradiator facility. No changes were detected in moisture, protein and ashes in gamma irradiated samples as compared to those of non-irradiated samples. Slight radiation effects were observed in the alveogram values and farinograph properties; the falling number decreased 11%, the absorption as well as the mixing tolerance were practically unchanged by irradiation. An increase of 15% in the stability value and a 29% in the dough development time were observed. Also the deformation energy decreased 7% with no change at all in the tenacity/extensibility factor. Total aerobic, yeast and mold counts were reduced 96%, 25% and 75%; respectively by the irradiation process. The obtained results confirm that gamma irradiation is effective in reducing the microbial load in bread making wheat flour without a significant change in the physicochemical and baking properties.

  7. Spoilage yeasts in the wine industry.

    PubMed

    Loureiro, V; Malfeito-Ferreira, M

    2003-09-01

    Yeasts play a central role in the spoilage of foods and beverages, mainly those with high acidity and reduced water activity (a(w)). A few species are capable of spoiling foods produced according to good manufacturing practices (GMPs). These can survive and grow under stress conditions where other microorganisms are not competitive. However, many of the aspects determining yeast spoilage have yet to be clarified. This critical review uses the wine industry as a case study where serious microbiological problems are caused by yeasts. First, the limitations of the available tools to assess the presence of spoilage yeasts in foods are discussed. Next, yeasts and factors promoting their colonisation in grapes and wines are discussed from the ecological perspective, demonstrating that a deeper knowledge of vineyard and winery ecosystems is essential to establish the origin of wine spoilage yeasts, their routes of contamination, critical points of yeast infection, and of course, their control. Further, zymological indicators are discussed as important tools to assess the microbiological quality of wines, although they are rarely used by the wine industry. The concepts of the susceptibility of wine to spoilage yeasts and wine stability are addressed based on scientific knowledge and industrial practices for monitoring yeast contamination. A discussion on acceptable levels of yeasts and microbiological criteria in the wine industry is supported by data obtained from wineries, wholesalers, and the scientific literature.Finally, future directions for applied research are proposed, involving collaboration between scientists and industry to improve the quality of wine and methods for monitoring the presence of yeast.

  8. The effect of sourdough and calcium propionate on the microbial shelf-life of salt reduced bread.

    PubMed

    Belz, Markus C E; Mairinger, Regina; Zannini, Emanuele; Ryan, Liam A M; Cashman, Kevin D; Arendt, Elke K

    2012-10-01

    The consumption of low-salt bread represents an efficient way to improve public health by decreasing cardiovascular health issues related to increased intakes of sodium chloride (NaCl). The reduction of NaCl influences the bread quality characteristics, in particular the shelf-life. Calcium propionate (CP) is commonly used in bread as an antifungal agent. Alternatively, sourdough can be used as a natural preservative. This work addresses the feasibility of NaCl reduction in wheat bread focussing on shelf-life and the compensation using sourdough as well as chemical preservatives. The impact of NaCl reduction and the addition of preservative agents in conjunction with different NaCl concentrations on the shelf-life of bread were tested under 'environmental' conditions in a bakery as well as using challenge tests against selected fungi. The challenge tests were performed using fungi commonly found in the bakery environment such as Penicillium expansum, Fusarium culmorum and Aspergillus niger. NaCl reduction decreased the shelf-life by 1-2 days. The addition of sourdough with antifungal activity prolonged the shelf-life to 12-14 days whereas the addition of 0.3 % calcium propionate prolonged the shelf-life to 10-12 days only. The fungal challenge tests revealed differences in the determined shelf-life between the different fungi based on their resistance. Similar antifungal performance was observed in sourdough breads and calcium propionate breads when tested against the different indicator moulds. The findings of this study indicate that addition of sourdough fermented using a specifically selected antifungal Lactobacillus amylovorus DSM 19280 can replace the chemical preservative calcium propionate addition and compensate for the reduced level and, therefore, guarantee the product safety of low-salt bread.

  9. 9 CFR 381.166 - Breaded products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition § 381... breading or a batter and breading in an amount not to exceed 30 percent of the weight of the...

  10. 9 CFR 381.166 - Breaded products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition § 381... breading or a batter and breading in an amount not to exceed 30 percent of the weight of the...

  11. 9 CFR 381.166 - Breaded products.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition § 381... breading or a batter and breading in an amount not to exceed 30 percent of the weight of the...

  12. Microbiological Spoilage of High-Sugar Products

    NASA Astrophysics Data System (ADS)

    Thompson, Sterling

    The high-sugar products discussed in this chapter are referred to as chocolate, sugar confectionery (non-chocolate), liquid sugars, sugar syrups, and honey. Products grouped in the sugar confectionery category include hard candy, soft/gummy candy, caramel, toffee, licorice, marzipan, creams, jellies, and nougats. A common intrinsic parameter associated with high-sugar products is their low water activity (a w), which is known to inhibit the growth of most spoilage and pathogenic bacteria. However, spoilage can occur as a result of the growth of osmophilic yeasts and xerophilic molds (Von Richter, 1912; Anand & Brown, 1968; Brown, 1976). The a w range for high-sugar products is between 0.20 and 0.80 (Banwart, 1979; Richardson, 1987; Lenovich & Konkel, 1992; ICMSF, 1998; Jay, Loessner, & Golden, 2005). Spoilage of products, such as chocolate-covered cherries, results from the presence of yeasts in the liquid sugar brine or the cherry. Generally, the spoiled product will develop leakers. The chocolate covering the cherry would not likely be a source of yeast contamination.

  13. Synergistic effect of Aspergillus tubingensis CTM 507 glucose oxidase in presence of ascorbic acid and alpha amylase on dough properties, baking quality and shelf life of bread.

    PubMed

    Kriaa, Mouna; Ouhibi, Rabeb; Graba, Héla; Besbes, Souhail; Jardak, Mohamed; Kammoun, Radhouane

    2016-02-01

    The impact of Aspergillus tubingensis glucose oxidase (GOD) in combination with α-amylase and ascorbic acid on dough properties, qualities and shelf life of bread was investigated. Regression models of alveograph and texture parameters of dough and bread were adjusted. Indeed, the mixture of GOD (44 %) and ascorbic acid (56 %) on flour containing basal improver showed its potential as a corrective action to get better functional and rheological properties of dough and bread texture. Furthermore, wheat flour containing basal additives and enriched with GOD (63.8 %), ascorbic acid (32 %) and α- amylase (4.2 %) led to high technological bread making parameters, to decrease the crumb firmness and chewiness and to improve elasticity, adhesion, cohesion and specific volume of bread. In addition to that, the optimized formulation addition significantly reduced water activity and therefore decreased bread susceptibility to microbial spoilage. These findings demonstrated that GOD could partially substitute not only ascorbic acid but also α-amylase. The generated models allowed to predict the behavior of wheat flour containing additives in the range of values tested and to define the additives formula that led to desired rheological and baking qualities of dough. This fact provides new perspectives to compensate flour quality deficiencies at the moment of selecting raw materials and technological parameters reducing the production costs and facilitating gluten free products development. Graphical abstractᅟ.

  14. Beer spoilage bacteria and hop resistance.

    PubMed

    Sakamoto, Kanta; Konings, Wil N

    2003-12-31

    For brewing industry, beer spoilage bacteria have been problematic for centuries. They include some lactic acid bacteria such as Lactobacillus brevis, Lactobacillus lindneri and Pediococcus damnosus, and some Gram-negative bacteria such as Pectinatus cerevisiiphilus, Pectinatus frisingensis and Megasphaera cerevisiae. They can spoil beer by turbidity, acidity and the production of unfavorable smell such as diacetyl or hydrogen sulfide. For the microbiological control, many advanced biotechnological techniques such as immunoassay and polymerase chain reaction (PCR) have been applied in place of the conventional and time-consuming method of incubation on culture media. Subsequently, a method is needed to determine whether the detected bacterium is capable of growing in beer or not. In lactic acid bacteria, hop resistance is crucial for their ability to grow in beer. Hop compounds, mainly iso-alpha-acids in beer, have antibacterial activity against Gram-positive bacteria. They act as ionophores which dissipate the pH gradient across the cytoplasmic membrane and reduce the proton motive force (pmf). Consequently, the pmf-dependent nutrient uptake is hampered, resulting in cell death. The hop-resistance mechanisms in lactic acid bacteria have been investigated. HorA was found to excrete hop compounds in an ATP-dependent manner from the cell membrane to outer medium. Additionally, increased proton pumping by the membrane bound H(+)-ATPase contributes to hop resistance. To energize such ATP-dependent transporters hop-resistant cells contain larger ATP pools than hop-sensitive cells. Furthermore, a pmf-dependent hop transporter was recently presented. Understanding the hop-resistance mechanisms has enabled the development of rapid methods to discriminate beer spoilage strains from nonspoilers. The horA-PCR method has been applied for bacterial control in breweries. Also, a discrimination method was developed based on ATP pool measurement in lactobacillus cells. However

  15. Advances in gluten-free bread technology.

    PubMed

    Ngemakwe, P H Nitcheu; Le Roes-Hill, M; Jideani, V A

    2015-06-01

    The unattractive appearance of gluten-free bread still remains a challenge in gluten-free breadmaking. In response to this, additives such as dairy products, soya and eggs have been used to improve the quality of gluten-free bread, but with limited success. In recent years, enzymes (transglutaminase and cyclodextrinase) and hydrocolloids (carboxymethylcellulose and hydroxypropylmethylcellulose) have become the main focus for the improvement of gluten-free bread. Transglutaminase has been shown to improve the dough viscoelasticity and decrease crumb hardness (6.84-5.73 N) of the resulting bread. Cyclodextrinase also enhances dough viscoelasticity, resulting in an improvement of 53% in shape index and crumb firmness. Similarly, hydroxypropylmethylcellulose improves gas retention and water absorption of dough and reduces crumb hardening rate of the resulting bread, while carboxymethylcellulose significantly increases dough elasticity (60-70 BU) and bread volume (230-267 cm(3)/100 g bread).

  16. Growth dynamics of specific spoilage organisms and associated spoilage biomarkers in chicken breast stored aerobically

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was performed to identify and quantify selected volatile spoilage biomarkers in a headspace over chicken breast using solid phase microextraction (SPME) combined with gas chromatography-mass spectrometry-flame ionization detectors (GC-MS/FID). The chicken breast samples were aerobically s...

  17. Preventing spoilage of poultry meat: focus on spoilage microorganisms and their control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The shelf-life of fresh poultry meat is determined by the level of contamination of processed meat by spoilage microorganisms, storage temperature and storage atmosphere. This chapter looks at the various ways by which to extend the shelf-life of poultry meat: vacuum and modified atmosphere packagin...

  18. Microbiological Spoilage of Acidified Specialty Products

    NASA Astrophysics Data System (ADS)

    Sperber, William H.

    Acidified specialty products or condiments are among the most microbiologically stable and safe food products. Often formulated, packaged, and distributed without heat treatments, they are microbiologically stable indefinitely at ambient temperatures in unopened containers. The packaged, acidified products are often intended for multiple uses, exposing them at the points of consumption to numerous opportunities for contamination with microorganisms. Nonetheless, they remain resistant to microbiological spoilage for many months, often under refrigerated conditions that are used to retard chemical reactions, flavor changes, and yeast growth.

  19. Microbiological Spoilage of Fish and Seafood Products

    NASA Astrophysics Data System (ADS)

    Gram, Lone

    Fish and seafood products are some of the most important protein sources in human nutrition. At the same time, these products are perishable and, if left unpreserved, spoil rapidly. Some fish products are heavily cured (salted, dried) and shelf stable at ambient temperature. An increasing number of fish products are preserved by low levels of salt, cooling, packaging in modified atmosphere, and/or addition of low levels of preservatives. The microflora of these products is often complex; however, spoilage is mostly caused by microbial action.

  20. Microbiological, Nutritional, and Sensory Quality of Bread Produced from Wheat and Potato Flour Blends

    PubMed Central

    Ijah, Udeme Joshua Josiah; Aduloju, Mercy Oluwayemisi; Aransiola, Sesan Abiodun

    2014-01-01

    Dehydrated uncooked potato (Irish and sweet) flour was blended by weight with commercial wheat flour at 0 to 10% levels of substitution to make bread. Comparative study of the microbial and nutritional qualities of the bread was undertaken. The total aerobic bacterial counts ranged from 3.0 × 105 cfu/g to 1.09 × 106 cfu/g while the fungal counts ranged from 8.0 × 101 cfu/g to 1.20 × 103 cfu/g of the sample. Coliforms were not detected in the bread. Bacteria isolated were species of Bacillus, Staphylococcus, and Micrococcus while fungi isolates were species of Aspergillus, Penicillium, Rhizopus, and Mucor. The mean sensory scores (color, aroma, taste, texture, and general acceptability) were evaluated. The color of the bread baked from WF/IPF2 (wheat/Irish potato flour, 95 : 5%) blend was preferred to WF (wheat flour, 100%) while WF/SPF1 (wheat/sweet potato flour, 100%) and WF/IPF1 (wheat/Irish potato flour, 90 : 10%) aroma were preferred to WF. However, the bread baked from WF, WF/IPF2 (wheat flour/Irish potato flour, 95 : 5%), and WF/SPF2 (wheat/sweet potato flour, 95 : 5%) was more acceptable than other blends. The use of hydrated potato flour in bread making is advantageous due to increased nutritional value, higher bread yield, and reduced rate of staling. PMID:26904642

  1. Biodiversity of spoilage lactobacilli: phenotypic characterisation.

    PubMed

    Sanders, J W; Oomes, S J C M; Membré, J-M; Wegkamp, A; Wels, M

    2015-02-01

    Preventing food spoilage is a challenge for the food industry, especially when applying mild preservation methods and when avoiding the use of preservatives. Therefore, it is essential to explore the boundaries of preservation by better understanding the causative microbes, their phenotypic behaviour and their genetic makeup. Traditionally in food microbiology, single strains or small sets of selected strains are studied. Here a collection of 120 strains of 6 different spoilage related Lactobacillus species and a multitude of sources was prepared and their growth characteristics determined in 384-well plates by optical density measurements (OD) over 20 days, for 20 carbon source-related phenotypic parameters and 25 preservation-related phenotypic parameters. Growth under all conditions was highly strain specific and there was no correlation of phenotypes at the species level. On average Lactobacillus brevis strains were amongst the most robust whereas Lactobacillus fructivorans strains had a much narrower growth range. The biodiversity data allowed the definition of preservation boundaries on the basis of the number of Lactobacillus strains that reached a threshold OD, which is different from current methods that are based on growth ability or growth rate of a few selected strains. Genetic information on these microbes and a correlation study will improve the mechanistic understanding of preservation resistance and this will support the future development of superior screening and preservation methods.

  2. An Automated Field Bakery System for Bread

    DTIC Science & Technology

    1983-10-01

    the bakery demonstrated to be able to make, proof and bake bread dough , continuously, at a rate of approximately 850 lbs of dough per hour. I Depanning...with continuous dough -making machinery, a total bread -making process of about one hour was demonstrated. It became clear that a continuous baking system...E), and divider/panner (F). 5 Artist concept of continuous proofer (A) and bake oven (B). Bread 17 from the dough maker enters proofer at the left. 6

  3. The Production of Synbiotic Bread by Microencapsulation

    PubMed Central

    Sharifan, Anousheh; Tarzi, Babak Ghiassi

    2016-01-01

    Summary Bread is a global staple food. Despite attempts to develop functional breads containing viable microorganisms, this has not been done yet because of the high temperature during baking. The aim of this study is to obtain synbiotic bread, hence hamburger bun and white pan bread were selected. Lactobacillus acidophilus LA-5 and L. casei 431 were encapsulated with calcium alginate and Hi-maize resistant starch via emulsion technique and coated with chitosan. The morphology and size of microcapsules were measured by scanning electron microscopy and particle size analyser. Inulin was added at 5% wheat flour mass basis for prebiotic effect. The encapsulated probiotics were inoculated into the bread dough and bread loaves were baked. The survival of encapsulated probiotics was determined after baking; also sensory evaluation was performed. Both types of bread met the standard criteria for probiotic products. The probiotic survival was higher in hamburger bun. L. casei 431 was more resistant to high temperature than L. acidophilus LA-5. A significant increase in probiotic survival was observed when the protective coating of chitosan was used in addition to calcium alginate and Hi-maize resistant starch. Storage for 4 days did not have any effect on the viability of encapsulated bacteria. The addition of encapsulated bacteria did not have any effect on flavour and texture; however, 5% inulin improved the texture of bread significantly. Results show that microencapsulation used in the production of synbiotic bread can enhance the viability and thermal resistance of the probiotic bacteria. PMID:27904393

  4. A loaf of bread: Price and value.

    PubMed

    Pearn, J

    1998-03-01

    In the Western world, the basic staple of nutrition is bread. It evolved, from Neolithic times in Mesopotamia and the Levant, from flour made from natural hybrids of emmer and einkorn. Its form has changed from that of a dark, coarse and heavy loaf, baked in the ashes, to the enriched artistic breads of the late twentieth century. Its variety of forms conferred status on those who ate its refined and whitened form. The wheel of fashion and nutrition has turned full circle to the quality-controlled, vitamin and mineral-enriched wholemeal loaf of the new millennium to come. Bread has changed from a staple not simply of nutrition itself, but to that of a 'functional food' whose fibre confers protection against preventible disease. The bread of the new century thus will be both a food and a medicine. So fundamental to Western life is bread, that its price has long been the last item to remain controlled, when all else is left to the dictates of a free market economy. Bread is the fundamental unit of exchange and forms the last link in a chain of commodities which starts from items of luxury to those of survival itself. The price of bread can thus be used as a currency datum. As such, the price of a loaf of bread, and the minutes of labour needed to produce it, can be used to measure the economy, and to give a measured perspective of its influence on a community's history. Costs, throughout history, can be expressed in 'bread units'. As such, the latter forms an absolute index of the worth of other items, particularly a person's labour. As such, bread and its value forms a partly independent measure of inflationary and other social influences. Bread remains a fundamental part not only of nutrition, but of life itself.

  5. Technological and chemical characters of bread prepared from irradiated wheat flour.

    PubMed

    Zaied, S E; Abdel-Hamid, A A; Attia, E A

    1996-02-01

    The present work is a part of research programme aimed to use gamma irradiation to decrease the growth of fungi and the concentration of mycotoxines which present naturally in collected samples of wheat flour from Egyptian markets (first part). To follow the technological, rheological and chemical characters of bread "Balady" common type in Egypt, same samples of wheat flour were irradiated with 2, 4 and 8 kGy for these purposes. The Egyptian bread type (Balady) had been prepared from irradiated and non-irraidated samples. The chemical analysis proved a significant induction in reducing sugars (RS) which increased gradually with increasing doses as 16.75%, 30.30%, 43.24% after using 2, 4 and 8 kGy respectively. Same trend was observed with total sugars (TS), less changes were observed in non-reducing sugars (NRS) and starch content. Results obtained showed that an actual reduction in dough development time, stability, weaking of dough and height of bread especially for irradiated samples at 4 and 8 kGy but 2 kGy was less effective. The reduction of Alkaline Water Retention Capacity (AWRC) was clear at high doses whereas 2.0 kGy improved the freshness of aged "balady" bread. Concerning, the evaluation of organoleptic characters of bread as judged by the panelists, all the samples were accepted either irradiated or not. But, the lowest values of acceptance resulted from irradiated samples with 4 and 8 kGy. Therefore, using 2 kGy can be recommended for keeping quality of wheat flour to avoid the infestation or pathogenic infection. Whereas high doses (4-8 kGy) can be use for eliminating the mycotoxins with some changes of quality which can be overcome by using some additional matters to get more acceptable bread and less changes in technological characters.

  6. Microbiological Spoilage of Spices, Nuts, Cocoa, and Coffee

    NASA Astrophysics Data System (ADS)

    Pinkas, Joan M.; Battista, Karen; Morille-Hinds, Theodora

    Spices, nuts, cocoa, and coffee are raw materials that may be used alone or as ingredients in the manufacture of processed food products. The control of microbiological spoilage of these raw materials at the ingredient stage will enable the food processor to better assure the production of high-quality foods with an acceptable shelf life. While this chapter is limited to four materials, many of the spoilage control procedures recommended can also be applied to other raw materials of a similar nature.

  7. Fungi and mycotoxins in silage: an overview.

    PubMed

    Alonso, V A; Pereyra, C M; Keller, L A M; Dalcero, A M; Rosa, C A R; Chiacchiera, S M; Cavaglieri, L R

    2013-09-01

    The present revision shows the early and current knowledge in the field of silage fungi and mycotoxins explaining the relevance of fungi and mycotoxins in silage. The problem does not end in animal disease or production losses as mycotoxins in feed can lead to the presence of their metabolic products in dairy products, which will be eventually affecting human health, mainly infants. Silage is green forage preserved by lactic fermentation under anaerobic conditions. This ecosystem maintains its quality and nutritional value depending on interactions among physical, chemical and biological agents. Forages used for ensilage are naturally in contact with yeasts and filamentous fungi, and the contamination often occurs in the field and can also occur during harvesting, transport, storage. Moreover, postharvest poor management can lead to a rapid spoilage. Studies on fungal contamination of dairy cattle feed have shown how corn silage influences the contamination degree of feed supplied to livestock. Increasing knowledge in this area will help elucidate the influence that this microbiota exerts on production and/or degradation of mycotoxins present in silage. Some of these fungi, although opportunist pathogens, are relevant epidemiologically and represent a high risk of contamination to farm workers who handle them improperly.

  8. 9 CFR 319.880 - Breaded products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... CERTIFICATION DEFINITIONS AND STANDARDS OF IDENTITY OR COMPOSITION Miscellaneous § 319.880 Breaded products. The... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Breaded products. 319.880 Section 319.880 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE...

  9. Xylanases from fungi: properties and industrial applications.

    PubMed

    Polizeli, M L T M; Rizzatti, A C S; Monti, R; Terenzi, H F; Jorge, J A; Amorim, D S

    2005-06-01

    Xylan is the principal type of hemicellulose. It is a linear polymer of beta-D-xylopyranosyl units linked by (1-4) glycosidic bonds. In nature, the polysaccharide backbone may be added to 4-O-methyl-alpha-D-glucuronopyranosyl units, acetyl groups, alpha-L-arabinofuranosyl, etc., in variable proportions. An enzymatic complex is responsible for the hydrolysis of xylan, but the main enzymes involved are endo-1,4-beta-xylanase and beta-xylosidase. These enzymes are produced by fungi, bacteria, yeast, marine algae, protozoans, snails, crustaceans, insect, seeds, etc., but the principal commercial source is filamentous fungi. Recently, there has been much industrial interest in xylan and its hydrolytic enzymatic complex, as a supplement in animal feed, for the manufacture of bread, food and drinks, textiles, bleaching of cellulose pulp, ethanol and xylitol production. This review describes some properties of xylan and its metabolism, as well as the biochemical properties of xylanases and their commercial applications.

  10. Breadings - What they are and how they are used

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three themes form the basis of this chapter for the Book of Batters and Breadings in Food Processing, 2nd edition published by AACC International. The first is the functional attributes of breadings - the relationships among physical characteristics of a breading to create breaded or "coated" foods...

  11. Antibiosis of vineyard ecosystem fungi against food-borne microorganisms.

    PubMed

    Cueva, Carolina; Moreno-Arribas, M Victoria; Bartolomé, Begoña; Salazar, Óscar; Vicente, M Francisca; Bills, Gerald F

    2011-12-01

    Fermentation extracts from fungi isolated from vineyard ecosystems were tested for antimicrobial activities against a set of test microorganisms, including five food-borne pathogens (Staphylococcus aureus EP167, Acinetobacter baumannii (clinically isolated), Pseudomonas aeruginosa PAO1, Escherichia coli O157:H7 (CECT 5947) and Candida albicans MY1055) and two probiotic bacteria (Lactobacillus plantarum LCH17 and Lactobacillus brevis LCH23). A total of 182 fungi was grown in eight different media, and the fermentation extracts were screened for antimicrobial activity. A total of 71 fungi produced extracts active against at least one pathogenic microorganism, but not against any probiotic bacteria. The Gram-positive bacterium S. aureus EP167 was more susceptible to antimicrobial fungi broth extracts than Gram-negative bacteria and pathogenic fungi. Identification of active fungi based on internal transcribed spacer rRNA sequence analysis revealed that species in the orders Pleosporales, Hypocreales and Xylariales dominated. Differences in antimicrobial selectivity were observed among isolates from the same species. Some compounds present in the active extracts were tentatively identified by liquid chromatography-mass spectrometry. Antimicrobial metabolites produced by vineyard ecosystem fungi may potentially limit colonization and spoilage of food products by food-borne pathogens, with minimal effect on probiotic bacteria.

  12. BREAD LOAF ROADLESS AREA, VERMONT.

    USGS Publications Warehouse

    Slack, John F.; Bitar, Richard F.

    1984-01-01

    On the basis of mineral-resource survey the Bread Loaf Roadless Area, Vermont, is considered to have probable resource potential for the occurrence of volcanogenic massive sulfide deposits of copper, zinc, and lead, particularly in the north and northeastern section of the roadless area. Nonmetallic commodities include minor deposits of sand and gravel, and abundant rock suitable for crushing. However, large amounts of these materials in more accessible locations are available outside the roadless area. A possibility exists that oil or natural gas resources may be present at great depth.

  13. Molecular identification of isolated fungi from stored apples in Riyadh, Saudi Arabia

    PubMed Central

    Alwakeel, Suaad S.

    2013-01-01

    Fungi causes most plant disease. When fruits are stored at suboptimal conditions, fungi grows, and some produce mycotoxin which can be dangerous for human consumption. Studies have shown that the Penicillium and Monilinia species commonly cause spoilage of fruits, especially apples. Several other genera and species were reported to grow to spoil fruits. This study was conducted to isolate and identify fruit spoilage by fungi on apples collected in Riyadh, Saudi Arabia and conduct a molecular identification of the fungal isolates. Thus, we collected 30 samples of red delicious and Granny Smith apples with obvious spoilage from different supermarkets between February and March of 2012 in Riyadh, Saudi Arabia. Each apple was placed in a sterile plastic bag in room temperature (25–30 °C) for six days or until fungal growth was evident all over the sample. Growth of fungal colonies on PDA was counted and sent for molecular confirmation by PCR. Six fruit spoilage fungi were isolated, including Penicillium chrysogenum, Penicillium adametzii, Penicillium chrysogenum, Penicillium steckii, Penicillium chrysogenum, and Aspergillus oryzae. P. chrysogenum was the most frequent isolate which was seen in 14 of a total of 34 isolates (41.2%), followed by P. adametzii and A. oryzae with seven isolates each (20.6%) and the least was P. steckii with six isolates (17.6%). Penicillium species comprised 27 of the total 34 (79.4%) isolates. Sequence analysis of the ITS regions of the nuclear encoded rDNA showed significant alignments for P. chrysogenum, P. adametzii and A. oryzae. Most of these fungal isolates are useful and are rarely pathogenic; however they can still produce severe illness in immune-compromised individuals, and sometimes otherwise healthy people may also become infected. It is therefore necessary to evaluate the possible production of mycotoxins by these fungi to determine a potential danger and to establish its epidemiology in order to develop adequate methods of

  14. Maillard reaction products in bread: A novel semi-quantitative method for evaluating melanoidins in bread.

    PubMed

    Helou, Cynthia; Jacolot, Philippe; Niquet-Léridon, Céline; Gadonna-Widehem, Pascale; Tessier, Frédéric J

    2016-01-01

    The aim of this study was to test the methods currently in use and to develop a new protocol for the evaluation of melanoidins in bread. Markers of the early and advanced stages of the Maillard reaction were also followed in the crumb and the crust of bread throughout baking, and in a crust model system. The crumb of the bread contained N(ε)-fructoselysine and N(ε)-carboxymethyllysine but at levels 7 and 5 times lower than the crust, respectively. 5-Hydroxymethylfurfural was detected only in the crust and its model system. The available methods for the semi-quantification of melanoidins were found to be unsuitable for their analysis in bread. Our new method based on size exclusion chromatography and fluorescence measures soluble fluorescent melanoidins in bread. These melanoidin macromolecules (1.7-5.6 kDa) were detected intact in both crust and model system. They appear to contribute to the dietary fibre in bread.

  15. Application of model bread baking in the examination of arabinoxylan-protein complexes in rye bread.

    PubMed

    Buksa, Krzysztof

    2016-09-05

    The changes in molecular mass of arabinoxylan (AX) and protein caused by bread baking process were examined using a model rye bread. Instead of the normal flour, the dough contained starch, water-extractable AX and protein which were isolated from rye wholemeal. From the crumb of selected model breads, starch was removed releasing AX-protein complexes, which were further examined by size exclusion chromatography. On the basis of the research, it was concluded that optimum model mix can be composed of 3-6% AX and 3-6% rye protein isolate at 94-88% of rye starch meaning with the most similar properties to low extraction rye flour. Application of model rye bread allowed to examine the interactions between AX and proteins. Bread baked with a share of AX, rye protein and starch, from which the complexes of the highest molar mass were isolated, was characterized by the strongest structure of the bread crumb.

  16. Identification of food and beverage spoilage yeasts from DNA sequence analyses.

    PubMed

    Kurtzman, Cletus P

    2015-11-20

    Detection, identification and classification of yeasts have undergone major changes in the last decade and a half following application of gene sequence analyses and genome comparisons. Development of a database (barcode) of easily determined DNA sequences from domains 1 and 2 (D1/D2) of the nuclear large subunit rRNA gene and from ITS now permits many laboratories to identify species quickly and accurately, thus replacing the laborious and often inaccurate phenotypic tests previously used. Phylogenetic analysis of gene sequences has resulted in a major revision of yeast systematics resulting in redefinition of nearly all genera. This new understanding of species relationships has prompted a change of rules for naming and classifying yeasts and other fungi, and these new rules are presented in the recently implemented International Code of Nomenclature for algae, fungi, and plants (Melbourne Code). The use of molecular methods for species identification and the impact of Code changes on classification will be discussed, especially in the context of food and beverage spoilage yeasts.

  17. Enhancing arabic bread quality and shelf life stability using bread improvers.

    PubMed

    Aleid, S M; Al-Hulaibi, A A; Ghoush, M Abu; Al-Shathri, A A

    2015-08-01

    Arabic breads is produced mainly from hard red winter wheat (HRWW) and have relatively little crumb, dense texture, form pocket and are often round with golden brown crust color. The objectives of this research were to investigate the effect of different bread improvers combinations addition in enhancing the quality parameters of Arabic bread. Therefore, the ability of Arabic bread for rolling, folding and overall quality were evaluated during the Arabic bread storage period for 2 days. It was found that there was significant effect of bread improvers combinations (Arabic gum "AG" * Mongglycerides "MG" *alpha-amylase) addition on the ability of Arabic bread for rolling and folding on the second day (P ≤ 0.1). The highest white Arabic bread quality was obtained significantly from addition of low AG, high of MG and high alpha-amylase combination and high AG, low of MG and high alpha-amylase combination. While, low of AG, high of MG and low alpha-amylase combination and high of AG, high of MG and low alpha-amylase combination significantly exhibited the highest overall quality for the Arabic bread made from whole flour.

  18. Non-Botrytis grape-rotting fungi responsible for earthy and moldy off-flavors and mycotoxins.

    PubMed

    Rousseaux, Sandrine; Diguta, Camelia Filofteia; Radoï-Matei, Florentina; Alexandre, Hervé; Guilloux-Bénatier, Michèle

    2014-04-01

    The grape microflora is complex and includes filamentous fungi, yeasts and bacteria with different physiological characteristics and effects on wine production. Most studies have focused on the wine microbiota, but a few studies have reported the ecology of grape microorganisms. Some of these organisms - such as non-Botrytis bunch rotting fungi, which greatly influence the safety or sensory quality of wine, due to the production of mycotoxins and off-flavors, respectively - are considered to be spoilage agents. We review here the diversity of filamentous fungi on grapes and the factors influencing their development, such as grape ripening stage, environmental factors (climate, rain and cultivation practices), grape variety and grape health status. We also discuss the pathways by which mycotoxins and off-flavors are produced, the control of the population, the metabolites responsible for wine spoilage and the methods for detecting and characterizing the microorganisms involved.

  19. Bacterial populations and the volatilome associated to meat spoilage.

    PubMed

    Casaburi, Annalisa; Piombino, Paola; Nychas, George-John; Villani, Francesco; Ercolini, Danilo

    2015-02-01

    Microbial spoilage of meat is a complex event to which many different bacterial populations can contribute depending on the temperature of storage and packaging conditions. The spoilage can derive from microbial development and consumption of meat nutrients by bacteria with a consequent release of undesired metabolites. The volatile organic compounds (VOCs) that are generated during meat storage can have an olfactory impact and can lead to rejection of the product when their concentration increase significantly as a result of microbial development. The VOCs most commonly identified in meat during storage include alcohols, aldehydes, ketones, fatty acids, esters and sulfur compounds. In this review, the VOCs found in fresh meat during storage in specific conditions are described together with the possible bacterial populations responsible of their production. In addition, on the basis of the data available in the literature, the sensory impact of the VOCs and their dynamics during storage is discussed to highlight their possible contribution to the spoilage of meat.

  20. Acetic acid bacteria spoilage of bottled red wine -- a review.

    PubMed

    Bartowsky, Eveline J; Henschke, Paul A

    2008-06-30

    Acetic acid bacteria (AAB) are ubiquitous organisms that are well adapted to sugar and ethanol rich environments. This family of Gram-positive bacteria are well known for their ability to produce acetic acid, the main constituent in vinegar. The oxidation of ethanol through acetaldehyde to acetic acid is well understood and characterised. AAB form part of the complex natural microbial flora of grapes and wine, however their presence is less desirable than the lactic acid bacteria and yeast. Even though AAB were described by Pasteur in the 1850s, wine associated AAB are still difficult to cultivate on artificial laboratory media and until more recently, their taxonomy has not been well characterised. Wine is at most risk of spoilage during production and the presence of these strictly aerobic bacteria in grape must and during wine maturation can be controlled by eliminating, or at least limiting oxygen, an essential growth factor. However, a new risk, spoilage of wine by AAB after packaging, has only recently been reported. As wine is not always sterile filtered prior to bottling, especially red wine, it often has a small resident bacterial population (<10(3) cfu/mL), which under conducive conditions might proliferate. Bottled red wines, sealed with natural cork closures, and stored in a vertical upright position may develop spoilage by acetic acid bacteria. This spoilage is evident as a distinct deposit of bacterial biofilm in the neck of the bottle at the interface of the wine and the headspace of air, and is accompanied with vinegar, sherry, bruised apple, nutty, and solvent like off-aromas, depending on the degree of spoilage. This review focuses on the wine associated AAB species, the aroma and flavour changes in wine due to AAB metabolism, discusses the importance of oxygen ingress into the bottle and presents a hypothesis for the mechanism of spoilage of bottled red wine.

  1. Development and analysis of composite flour bread.

    PubMed

    Menon, Lakshmi; Majumdar, Swarnali Dutta; Ravi, Usha

    2015-07-01

    The study elucidates the effect of utilizing cereal-pulse-fruit seed composite flour in the development and quality analysis of leavened bread. The composite flour was prepared using refined wheat flour (WF), high protein soy flour (SF), sprouted mung bean flour (MF) and mango kernel flour (MKF). Three variations were formulated such as V-I (WF: SF: MF: MKF = 85:5:5:5), V-II (WF: SF: MF: MKF = 70:10:10:10), and V-III (WF: SF: MF: MKF = 60:14:13:13). Pertinent functional, physico-chemical and organoleptic attributes were studied in composite flour variations and their bread preparations. Physical characteristics of the bread variations revealed a percentage decrease in loaf height (14 %) and volume (25 %) and 20 % increase in loaf weight with increased substitution of composite flour. The sensory evaluation of experimental breads on a nine-point hedonic scale revealed that V-I score was 5 % higher than the standard bread. Hence, the present study highlighted the nutrient enrichment of bread on incorporation of a potential waste material mango kernel, soy and sprouted legume. Relevant statistical tests were done to analyze the significance of means for all tested parameters.

  2. Home-Made Breads [and] Home-Baked Breads for Busy People.

    ERIC Educational Resources Information Center

    Kirk, John

    This packet contains two lesson plans for a class on making bread to be taught in an adult literacy program. Developed by a teacher who has taught the classes to 175 people, the lesson plans each contain complete directions for working with students while baking bread. One lesson plan is for experienced home bakers, and the other is a simpler…

  3. Spoilage of chicken skin at 2 degrees C: electron microscopic study.

    PubMed Central

    Thomas, C J; McMeekin, T A

    1981-01-01

    Microscopic techniques were used in conjunction with normal microbiological procedures to examine the development of the spoilage microflora on the skin of chicken carcasses held at 2 degrees C. Pigmented and nonpigmented psychrotrophic pseudomonads were the major spoilage bacteria isolated at all stages of storage examined. The spoilage microflora grow within a liquid film covering the skin surface, as well as in feather follicle shafts. Penetration and disruption of skin tissue were not observed even after onset of organoleptic spoilage. Bacteria were not attached to the skin by extracellular bridging substances. These data suggest a nonspecific histological-microbiological relationship between he spoilage association and the skin substrate. Images PMID:7195190

  4. Metabolic strategies of beer spoilage lactic acid bacteria in beer.

    PubMed

    Geissler, Andreas J; Behr, Jürgen; von Kamp, Kristina; Vogel, Rudi F

    2016-01-04

    Beer contains only limited amounts of readily fermentable carbohydrates and amino acids. Beer spoilage lactic acid bacteria (LAB) have to come up with metabolic strategies in order to deal with selective nutrient content, high energy demand of hop tolerance mechanisms and a low pH. The metabolism of 26 LAB strains of 6 species and varying spoilage potentialwas investigated in order to define and compare their metabolic capabilities using multivariate statistics and outline possible metabolic strategies. Metabolic capabilities of beer spoilage LAB regarding carbohydrate and amino acids did not correlate with spoilage potential, but with fermentation type (heterofermentative/homofermentative) and species. A shift to mixed acid fermentation by homofermentative (hof) Pediococcus claussenii and Lactobacillus backii was observed as a specific feature of their growth in beer. For heterofermentative (hef) LAB a mostly versatile carbohydrate metabolism could be demonstrated, supplementing the known relevance of organic acids for their growth in beer. For hef LAB a distinct amino acid metabolism, resulting in biogenic amine production, was observed, presumably contributing to energy supply and pH homeostasis.

  5. Characteristics of spoilage-associated secondary cucumber fermentation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Secondary fermentations during the bulk storage of fermented cucumbers can result in spoilage that causes a total loss of the fermented product, at an estimated cost of $6,000 to $15,000 per affected tank. Previous research has suggested that such fermentations are the result of microbiological util...

  6. Turning Bread into Rocks: A Multisensory Unit Opener.

    ERIC Educational Resources Information Center

    Smith, Shaw

    2000-01-01

    Presents an earth science activity on rocks to demonstrate the vital links between minerals and rocks. Uses different kinds of breads to demonstrate that rocks, like breads, are composed of various ingredients in different proportions. (ASK)

  7. Formation of Guaiacol by Spoilage Bacteria from Vanillic Acid, a Product of Rice Koji Cultivation, in Japanese Sake Brewing.

    PubMed

    Ito, Toshihiko; Konno, Mahito; Shimura, Yoichiro; Watanabe, Seiei; Takahashi, Hitoshi; Hashizume, Katsumi

    2016-06-08

    The formation of guaiacol, a potent phenolic off-odor compound in the Japanese sake brewing process, was investigated. Eight rice koji samples were analyzed, and one contained guaiacol and 4-vinylguaiacol (4-VG) at extraordinarily high levels: 374 and 2433 μg/kg dry mass koji, respectively. All samples contained ferulic and vanillic acids at concentrations of mg/kg dry mass koji. Guaiacol forming microorganisms were isolated from four rice koji samples. They were identified as Bacillus subtilis, B. amyloliquefaciens/subtilis, and Staphylococcus gallinarum using 16S rRNA gene sequence. These spoilage bacteria convert vanillic acid to guaiacol and ferulic acid to 4-VG. However, they convert very little ferulic acid or 4-VG to guaiacol. Nine strains of koji fungi tested produced vanillic acid at the mg/kg dry mass koji level after cultivation. These results indicated that spoilage bacteria form guaiacol from vanillic acid, which is a product of koji cultivation in the sake brewing process.

  8. Quality of Bread Supplemented with Antrodia
salmonea-Fermented Grains

    PubMed Central

    Chien, Rao-Chi; Ulziijargal, Enkhjargal

    2016-01-01

    Summary Fermented grains of buckwheat, oat, embryo rice and wheat, which were prepared by solid-state fermentation with Antrodia salmonea, and the mycelium was used to substitute 7% of wheat flour to make bread. No difference in proximate composition, texture profile and contents of non-volatile taste components was observed among bread samples. White bread and bread supplemented with mycelium and fermented grains looked different. Bread supplemented with fermented grains had similar thermal properties, which differed from those of white bread and bread supplemented with mycelium. Bread supplemented with fermented grains contained substantial mass fractions (on dry mass basis) of adenosine (0.92–1.96 µg/g), ergosterol (24.53–30.12 µg/g), ergothioneine (2.16–3.18 µg/g) and γ-aminobutyric acid (2.20–2.45 µg/g). In addition, bread supplemented with mycelium contained lovastatin (0.43 µg/g). White bread and bread supplemented with fermented grains had similar sensory results. Overall, fermented grains could be incorporated into bread to provide beneficial effects. PMID:27904408

  9. Manufacture of gluten-free specialty breads and confectionery products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    People suffering from celiac disease, wheat allergies or wheat intolerances require breads not containing any wheat or related cereals like rye and barley. The manufacture of these so-called gluten-free breads is not well understood and much less literature is available than on wheat breads. On the ...

  10. BreadNet: An On-Line Community.

    ERIC Educational Resources Information Center

    Walker, Susan

    1987-01-01

    Describes BreadNet, a computer network linking Middlebury College English teachers, their associates, and students. Network extends to rural English teachers and their K-8 students. BreadNet used for student pen pal program, teacher teleconferencing, information access. Also describes BreadNet's problems and future possibilities. (TES)

  11. Quality of Bread Supplemented with Antrodia
salmonea-Fermented Grains.

    PubMed

    Chien, Rao-Chi; Ulziijargal, Enkhjargal; Mau, Jeng-Leun

    2016-06-01

    Fermented grains of buckwheat, oat, embryo rice and wheat, which were prepared by solid-state fermentation with Antrodia salmonea, and the mycelium was used to substitute 7% of wheat flour to make bread. No difference in proximate composition, texture profile and contents of non-volatile taste components was observed among bread samples. White bread and bread supplemented with mycelium and fermented grains looked different. Bread supplemented with fermented grains had similar thermal properties, which differed from those of white bread and bread supplemented with mycelium. Bread supplemented with fermented grains contained substantial mass fractions (on dry mass basis) of adenosine (0.92-1.96 µg/g), ergosterol (24.53-30.12 µg/g), ergothioneine (2.16-3.18 µg/g) and γ-aminobutyric acid (2.20-2.45 µg/g). In addition, bread supplemented with mycelium contained lovastatin (0.43 µg/g). White bread and bread supplemented with fermented grains had similar sensory results. Overall, fermented grains could be incorporated into bread to provide beneficial effects.

  12. Everyone Eats Bread: A Multicultural Unit for First Graders.

    ERIC Educational Resources Information Center

    Belanus, Betty J.; Kerst, Catherine H.

    This multicultural teaching unit was developed and tested with the first grade classes of Glenhaven Elementary School, Wheaton, Maryland. The lessons focus on bread as a common food in the world but explores the many types of bread and its symbolism. The unit is divided into four parts. Part 1, "Introduction to Bread," contains lessons…

  13. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with the provisions of § 161.175, except that it contains not less than 65 percent of shrimp material, as...

  14. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with the provisions of § 161.175, except that it contains not less than 65 percent of shrimp material, as...

  15. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with the provisions of § 161.175, except that it contains not less than 65 percent of shrimp material, as...

  16. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with the provisions of § 161.175, except that it contains not less than 65 percent of shrimp material, as...

  17. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  18. 21 CFR 161.176 - Frozen raw lightly breaded shrimp.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Frozen raw lightly breaded shrimp. 161.176 Section 161.176 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Shellfish § 161.176 Frozen raw lightly breaded shrimp. Frozen raw lightly breaded shrimp complies with...

  19. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  20. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  1. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  2. 21 CFR 136.130 - Milk bread, rolls, and buns.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., buttermilk product, cheese whey, cheese whey product, or milk protein is used. (b) The name of the food is... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Milk bread, rolls, and buns. 136.130 Section 136....130 Milk bread, rolls, and buns. (a) Each of the foods milk bread, milk rolls, and milk buns...

  3. Chemical ecology of fungi.

    PubMed

    Spiteller, Peter

    2015-07-01

    Fungi are widespread in nature and have conquered nearly every ecological niche. Fungi occur not only in terrestrial but also in freshwater and marine environments. Moreover, fungi are known as a rich source of secondary metabolites. Despite these facts, the ecological role of many of these metabolites is still unknown and the chemical ecology of fungi has not been investigated systematically so far. This review intends to present examples of the various chemical interactions of fungi with other fungi, plants, bacteria and animals and to give an overview of the current knowledge of fungal chemical ecology.

  4. Characterization and control of Mucor circinelloides spoilage in yogurt.

    PubMed

    Snyder, Abigail B; Churey, John J; Worobo, Randy W

    2016-07-02

    Consumer confidence in the food industry is severely affected by large-scale spoilage incidents. However, relatively little research exists on spoilage potential of members of the fungal subphylum Mucormycotina (e.g. Mucor), which includes dimorphic spoilage organisms that can switch between a yeast-like and hyphal phase depending on environmental conditions. The presence of Mucor circinelloides in yogurt may not cause spoilage, but growth and subsequent changes in quality (e.g. container bloating) can cause spoilage if not controlled. The purpose of this study was to evaluate the effects on M. circinelloides of pasteurization regimen, natamycin concentrations, and storage temperature in yogurt production, as measured by fungal proliferation and carbon dioxide production. A strain of M. circinelloides isolated from commercially spoiled yogurt showed greater yogurt-spoilage potential than clinical isolates and other industrial strains. D-values and z-values were determined for the spoilage isolate in milk as an evaluation of the fungus' ability to survive pasteurization. Natamycin was added to yogurt at 0, 5, 10, 15, and 20ppm (μg/ml) to determine its ability to inhibit M. circinelloides over the course of month-long challenge studies at 4°C, 15°C, and 25°C. Survivors were recovered on acidified PDA and carbon dioxide levels were recorded. The D-values at 54°C, 56°C, and 58°C for hyphae/sporangiospores were (in min) 38.31±0.02, 10.17±0.28, and 1.94±0.53, respectively, which yielded a z-value of 3.09°C. The D-values at 51°C, 53°C, and 55°C for yeast-like cells were (in min) 14.25±0.12, 6.87±1.19, and 2.44±0.35, respectively, which yielded a z-value of 0.34°C. These results indicated that M. circinelloides would not survive fluid milk pasteurization if contamination occurred prior to thermal treatment. CO2 production was only observed when M. circinelloides was incubated under low-oxygen conditions, and occurred only at temperatures above 4

  5. Volatiles produced by microorganisms isolated from refrigerated chicken at spoilage.

    PubMed Central

    Freeman, L R; Silverman, G J; Angelini, P; Merritt, C; Esselen, W B

    1976-01-01

    Volatile components present at spoilage of refrigerated chicken breasts were identified using high-vacuum-low-temperature distillation techniques followed by analysis with combined temperature-programmed gas chromatography and mass spectrometry. A comparison was made of the compounds detected from both irradiated and non-irradiated muscle stored at 2 and 10 degrees C under both aerobic and anaerobic conditions. Isolates were randomly selected from the spoiled poultry, identified, and evaluated for their ability to produce volatile spoilage noted when grown on radiation-sterilized chicken. Several isolates that produced off-odors on sterile chicken breasts were examined. Twenty-two compounds were associated with spoilage. Some of the compounds found on both irradiated and unirradiated samples were considered to play only a minor role in the spoilage aroma or were present in low concentrations, since the aroma of spoiled irradiated chicken lacked the harsh odor notes typical of spoiled unirradiated chicken. Fifteen of the 22 compounds were considered to be unique to unirradiated, aerobically spoiled samples. Nine of these compounds, hydrogen sulfide, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, methyl acetate, ethyl acetate, heptadiene, methanol, and ethanol, were found on chicken spoiled at both 2 and 10 degrees C. xylene, benzaldehyde, and 2,3-dithiahexane were detected only in samples stored at 2 degrees C and methyl thiolacetate, 2-butanone, and ethyl propionate were associated with 10 degrees C spoilage. Fifty-eight isolates randomly selected from fresh, radiation-pasteurized, and unirradiated spoiled poultry were classified taxonomically, and 10 of them, which produced spoilage odors on sterilized chicken breasts, were selected for subsequent analysis of their volatiles. Isolates identified as Pseudomonas putrefaciens and Pseudomonas species that were members of groups I and II of Shewan's classification, as well as Flavobacterium and oxidative

  6. Terpenoids from endophytic fungi.

    PubMed

    de Souza, Jucimar Jorgeane; Vieira, Ivo José Curcino; Rodrigues-Filho, Edson; Braz-Filho, Raimundo

    2011-12-19

    This work reviews the production of terpenoids by endophytic fungi and their biological activities, in period of 2006 to 2010. Sixty five sesquiterpenes, 45 diterpenes, five meroterpenes and 12 other terpenes, amounting to 127 terpenoids were isolated from endophytic fungi.

  7. "Green preservatives": combating fungi in the food and feed industry by applying antifungal lactic acid bacteria.

    PubMed

    Pawlowska, Agata M; Zannini, Emanuele; Coffey, Aidan; Arendt, Elke K

    2012-01-01

    Fungal food spoilage plays a pivotal role in the deterioration of food and feed systems and some of them are also able to produce toxic compounds for humans and animals. The mycotoxins produced by fungi can cause serious health hazards, including cancerogenic, immunotoxic, teratogenic, neurotoxic, nephrotoxic and hepatotoxic effects, and Kashin-Beck disease. In addition to this, fungal spoilage/pathogens are causing losses of marketable quality and hygiene of foodstuffs, resulting in major economic problem throughout the world. Nowadays, food spoilage can be prevented using physical and chemical methods, but no efficient strategy has been proposed so far to reduce the microbial growth ensuring public health. Therefore, lactic acid bacteria (LAB) can play an important role as natural preservatives. The protection of food products using LAB is mainly due to the production of antifungal compounds such as carboxylic acids, fatty acids, ethanol, carbon dioxide, hydrogen peroxide, and bacteriocins. In addition to this, LAB can also positively contribute to the flavor, texture, and nutritional value of food products. This review mainly focuses on the use of LAB for food preservation given their extensive industrial application in a wide range of foods and feeds. The attention points out the several industrial patents concerning the use of antifungal LAB as biocontrol agent against spoilage organisms in different fermented foods and feeds.

  8. Long-Term Fungal Inhibition by Pisum sativum Flour Hydrolysate during Storage of Wheat Flour Bread

    PubMed Central

    Lavecchia, Anna; Gramaglia, Valerio; Gobbetti, Marco

    2015-01-01

    In order to identify antifungal compounds from natural sources to be used as ingredients in the bakery industry, water/salt-soluble extracts (WSE) from different legume flour hydrolysates obtained by the use of a fungal protease were assayed against Penicillium roqueforti DPPMAF1. The agar diffusion assays allowed the selection of the pea (Pisum sativum) hydrolysate as the most active. As shown by the hyphal radial growth rate, the WSE had inhibitory activity towards several fungi isolated from bakeries. The MIC of the WSE was 9.0 mg/ml. Fungal inhibition was slightly affected by heating and variations in pH. The antifungal activity was attributed to three native proteins (pea defensins 1 and 2 and a nonspecific lipid transfer protein [nsLTP]) and a mixture of peptides released during hydrolysis. The three proteins have been reported previously as components of the defense system of the plant. Five peptides were purified from WSE and were identified as sequences encrypted in leginsulin A, vicilin, provicilin, and the nsLTP. To confirm antifungal activity, the peptides were chemically synthesized and tested. Freeze-dried WSE were used as ingredients in leavened baked goods. In particular, breads made by the addition of 1.6% (wt/wt) of the extract and fermented by baker's yeast or sourdough were characterized for their main chemical, structural, and sensory features, packed in polyethylene bags, stored at room temperature, and compared to controls prepared without pea hydrolysate. Artificially inoculated slices of a bread containing the WSE did not show contamination by fungi until at least 21 days of storage and behaved like the bread prepared with calcium propionate (0.3%, wt/wt). PMID:25862230

  9. Composition and antimicrobial properties of Sardinian Juniperus essential oils against foodborne pathogens and spoilage microorganisms.

    PubMed

    Cosentino, Sofia; Barra, Andrea; Pisano, Barbara; Cabizza, Maddalena; Pirisi, Filippo Maria; Palmas, Francesca

    2003-07-01

    In this work, the chemical compositions and antimicrobial properties of Juniperus essential oils and of their main components were determined. Five berry essential oils obtained from different species of Juniperus growing wild in Sardinia were analyzed. The components of the essential oils were identified by gas chromatography-mass spectrometry (GC-MS) analysis. The antimicrobial activities of the oils and their components against food spoilage and pathogenic microorganisms were determined by a broth microdilution method. The GC-MS analysis showed a certain variability in the concentrations of the main constituents of the oils. Alpha-pinene was largely predominant in the oils of the species J. phoenicea subsp. turbinata and J. oxycedrus. Alpha-pinene and myrcene constituted the bulk (67.56%) of the essential oil of J. communis. Significant quantitative differences were observed for myrcene, delta-3-carene, and D-germacrene. The results of the antimicrobial assay show that the oils of J. communis and J. oxycedrus failed to inhibit any of the microorganisms at the highest concentrations tested (MLC > or = 900 microg/ml), while the oils extracted from J. turbinata specimens were active against fungi, particularly against a strain of Aspergillus flavus (an aflatoxin B1 producer). Of the single compounds tested, delta-3-carene was found to possess the broadest spectrum of activity and appeared to contribute significantly to the antifungal activity observed for J. turbinata oils. This activity may be helpful in the prevention of aflatoxin contamination for many foods.

  10. Predicting and preventing mold spoilage of food products.

    PubMed

    Dagnas, Stéphane; Membré, Jeanne-Marie

    2013-03-01

    This article is a review of how to quantify mold spoilage and consequently shelf life of a food product. Mold spoilage results from having a product contaminated with fungal spores that germinate and form a visible mycelium before the end of the shelf life. The spoilage can be then expressed as the combination of the probability of having a product contaminated and the probability of mold growth (germination and proliferation) up to a visible mycelium before the end of the shelf life. For products packed before being distributed to the retailers, the probability of having a product contaminated is a function of factors strictly linked to the factory design, process, and environment. The in-factory fungal contamination of a product might be controlled by good manufacturing hygiene practices and reduced by particular processing practices such as an adequate air-renewal system. To determine the probability of mold growth, both germination and mycelium proliferation can be mathematically described by primary models. When mold contamination on the product is scarce, the spores are spread on the product and more than a few spores are unlikely to be found at the same spot. In such a case, models applicable for a single spore should be used. Secondary models can be used to describe the effect of intrinsic and extrinsic factors on either the germination or proliferation of molds. Several polynomial models and gamma-type models quantifying the effect of water activity and temperature on mold growth are available. To a lesser extent, the effect of pH, ethanol, heat treatment, addition of preservatives, and modified atmospheres on mold growth also have been quantified. However, mold species variability has not yet been properly addressed, and only a few secondary models have been validated for food products. Once the probability of having mold spoilage is calculated for various shelf lives and product formulations, the model can be implemented as part of a risk management

  11. Identification of beer spoilage microorganisms using the MALDI Biotyper platform.

    PubMed

    Turvey, Michelle Elizabeth; Weiland, Florian; Meneses, Jon; Sterenberg, Nick; Hoffmann, Peter

    2016-03-01

    Beer spoilage microorganisms present a major risk for the brewing industry and can lead to cost-intensive recall of contaminated products and damage to brand reputation. The applicability of molecular profiling using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) in combination with Biotyper software was investigated for the identification of beer spoilage microorganisms from routine brewery quality control samples. Reference mass spectrum profiles for three of the most common bacterial beer spoilage microorganisms (Lactobacillus lindneri, Lactobacillus brevis and Pediococcus damnosus), four commercially available brewing yeast strains (top- and bottom-fermenting) and Dekkera/Brettanomyces bruxellensis wild yeast were established, incorporated into the Biotyper reference library and validated by successful identification after inoculation into beer. Each bacterial species could be accurately identified and distinguished from one another and from over 5600 other microorganisms present in the Biotyper database. In addition, wild yeast contaminations were rapidly detected and distinguished from top- and bottom-fermenting brewing strains. The applicability and integration of mass spectrometry profiling using the Biotyper platform into existing brewery quality assurance practices within industry were assessed by analysing routine microbiology control samples from a local brewery, where contaminating microorganisms could be reliably identified. Brewery-isolated microorganisms not present in the Biotyper database were further analysed for identification using LC-MS/MS methods. This renders the Biotyper platform a promising candidate for biological quality control testing within the brewing industry as a more rapid, high-throughput and cost-effective technology that can be tailored for the detection of brewery-specific spoilage organisms from the local environment.

  12. Estimation of bacteriological spoilage of pork cutlets by electronic nose.

    PubMed

    Horváth, Kinga M; Seregély, Zs; Dalmadi, I; Andrássy, Eva; Farkas, J

    2007-06-01

    The utility of chemosensor array (EN) signals of head-space volatiles of aerobically stored pork cutlets as a non-invasive technique for monitoring their microbiological load was studied during storage at 4, 8 and 12 degrees C, respectively. The bacteriological quality of the meat samples was determined by standard total aerobic plate counts (TAPC) and colony count of selectively estimated Pseudomonas (PS) spp., the predominant aerobic spoilage bacteria. Statistical analysis of the electronic nose measurements were principal component analysis (PCA), and canonical discriminant analysis (CDA). Partial least squares (PLS) regression was used to model correlation between microbial loads and EN signal responses, the degree of bacteriological spoilage, independently of the temperature of the refrigerated storage. Sensor selection techniques were applied to reduce the dimensionality and more robust calibration models were computed by determining few individual sensors having the smallest cross correlations and highest correlations with the reference data. Correlations between the predicted and "real" values were given on cross-validated data from both data reduced models and for full calibrations using the 23 sensor elements. At the same time, sensorial quality of the raw cutlets was noted subjectively on faultiness of the odour and colour, and drip formation of the samples. These preliminary studies indicated that the electronic nose technique has a potential to detect bacteriological spoilage earlier or at the same time as olfactory quality deterioration.

  13. Leuconostoc spoilage of vacuum-packaged vegetable sausages.

    PubMed

    Vihavainen, Elina J; Murros, Anna E; Björkroth, K Johanna

    2008-11-01

    The present study was conducted to assess the role of lactic acid bacteria (LAB) in spoilage of a vacuum-packaged vegetable sausage product. This spoilage problem was characterized by formation of gas and slime, and was limiting the shelf life of the product. To investigate the LAB populations, LAB were enumerated in vegetable sausages graded as either spoiled or acceptable. From these vegetable sausages, 110 prevailing LAB isolates were recovered and identified using an LAB ribotyping database, which uses HindIII restriction fragment length polymorphism patterns of the 16S and 23S rRNA genes as operational taxonomic units. Finally, to determine the effects of the prevailing LAB on the sensory properties of the product, fresh vegetable sausages were inoculated with six LAB strains. The results revealed that Leuconostoc gelidum, Leuconostoc gasicomitatum, and Leuconostoc mesenteroides were the predominant LAB in the commercial vegetable sausages. The inoculation of these LAB onto vegetable sausages resulted in the formation of gas, slime, and a sour off-odor. Based on these findings, L. gelidum, L gasicomitatum, and L. mesenteroides were responsible for spoilage of the vegetable sausage product.

  14. 9 CFR 381.166 - Breaded products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Breaded products. 381.166 Section 381.166 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION POULTRY PRODUCTS INSPECTION REGULATIONS Definitions and Standards of Identity or Composition §...

  15. Staling white pan bread: fundamental causes.

    PubMed

    Kulp, K; Ponte, J G

    1981-01-01

    Staling, as it is applied to bakery foods, is a generic term covering a number of changes that occur in the products during normal storage. Consumers judge staleness by direct perception, which provides a subjective estimate that represents an unconscious integration of many factors. This review will discuss the main components of staling: (1) physicochemical changes of bread and related products (firming and texture deterioration of crumb and loss of crispness of crust) and (2) flavor changes. Section I will cover current theories of changes of firming and textural changes. The starch component of flour is generally considered to be responsible for these staling reactions. Consequently, the physicochemical involvement of amylose, amylopectin in these reactions will be fully discussed and current evidence supporting these theories (rheological, chemical, X-rays) will be given. Interactions of starch and surface active agents and other complexing compounds will be presented in Section II. In Section III, contribution of minor flour components and bakery food ingredients will be evaluated. Section IV will focus on organoleptic deterioration of products, presenting flavor changes that were observed during staling bread. Section V will discuss structural changes of breads caused by enzymolysis during bread production and storage as related to staling. Following the theoretical section (Sections I to V), Section VI will focus on practical control of staling. This discussion will cover the following factors: formulation, surfactants, enzymes, storage, freezing, and packaging.

  16. Developments in bread-making processes.

    PubMed

    Belderok, B

    2000-01-01

    An introduction to the evolutionary history of wheat is followed by a description of the origin and distribution of the modern hexaploid wheat varieties in Europe. Next, the influence of cultural (the way of bread making), social and economic (i.e. the great influence of the United States and Canada) factors on wheat growing in Europe are considered (Section 1). The anatomy and chemical composition of wheat grains and the fundamental differences between hard and soft wheat are described in Section 2. The process of flour making is treated in Section 3. Section 4 contains a study of gluten proteins and wheat starches in relation to the making of bread (Section 5) and of other wheat products (Section 6). Section 7 deals with the genetic bread-wheat properties: grain hardness, milling quality, production of (unwanted) sticky doughs, alpha-amylase levels, and contains an extensive study of genetics and the role of gliadins and glutenins. A concluding section contains the description and evaluation of assay methods to identify the characteristics of bread wheats for the use of millers, arbiters, and especially for growers.

  17. The Bread Loaf Writing Grants Program.

    ERIC Educational Resources Information Center

    Middlebury Coll., VT. Bread Loaf School of English

    Illustrating that the Bread Loaf Grants Program is cost-effective and beneficial, this collection presents reports and articles by and about teachers and students involved in staff and curriculum development projects funded by the program. The collection concludes that the projects demonstrate that literacy flourishes in settings where children…

  18. Whole grain gluten-free flat breads

    Technology Transfer Automated Retrieval System (TEKTRAN)

    USDA food guide recommends that at least ½ of all the grains eaten should be whole grains. FDA allows label health claims for food containing 11 g and 51% whole grains. This is the only report demonstrating innovative whole grain products. Whole grain gluten-free flat breads were prepared with cor...

  19. Exopolysaccharides from co-cultures of Weissella confusa 11GU-1 and Propionibacterium freudenreichii JS15 act synergistically on wheat dough and bread texture.

    PubMed

    Tinzl-Malang, Saskia Katharina; Rast, Peter; Grattepanche, Franck; Sych, Janice; Lacroix, Christophe

    2015-12-02

    The storage of bread is limited by both physical (staling) and microbial (mainly fungal) spoilage. Exopolysaccharides (EPS) produced by lactic acid bacteria (LAB) and organic acids from propionibacteria (PAB) have been used to enhance texture and extend shelf-life of bakery products. In this study the functionality of EPS of Weissella confusa A3/2-1 (dextran), W. confusa F3/2-2 (dextran and levan), W. confusa 11GU-1 (dextran and ropy capsular polysaccharide) was evaluated in wheat bread. Two strains of Propionibacterium freudenreichii (Pf), shown to produce a heteropolysaccharide (Pf JS15) or a β-glucan (Pf DF30), were tested in single and mixed cultures with W. confusa (Wc). The EPS fermentates were prepared by batch fermentation of cereal- or malt-based medium using sucrose (Wc) or lactic acid (Pf) as carbon source. Incorporation of EPS from single culture fermentates and 1:1 Weissella-Propionibacterium fermentate mixtures revealed strong positive effects of dextran and ropy capsular polysaccharide produced by Wc 11GU-1 on bread staling retardation, with synergistic effects of EPS mixture from Wc 11GU-1 and Pf JS15. A co-fermentation of Wc 11GU-1 and Pf JS15 was developed to produce EPS together with antifungal organic acid mixture (acetate and propionate) in a single step process. The addition of 15% (w/w flour base) co-culture, yielding EPS, acetate and propionate concentrations of 1.5, 0.5 and 1g/kg dough, respectively, resulted in improved bread texture, increased loaf volume and decreased crumb firming during storage for 3days compared with control breads and breads supplemented with equivalent levels of chemical organic acids. Our data showed that EPS could compensate for the negative effects of chemical acetate and propionate in a concentration range exerting antifungal effects. The natural bioingredient produced by Wc 11GU-1 and Pf JS15 has potential for applications as antifungal, texture-building and anti-staling agent in breads, consistent with

  20. Extreme resistance to weak-acid preservatives in the spoilage yeast Zygosaccharomyces bailii☆

    PubMed Central

    Stratford, Malcolm; Steels, Hazel; Nebe-von-Caron, Gerhard; Novodvorska, Michaela; Hayer, Kimran; Archer, David B.

    2013-01-01

    Weak-acid preservatives, such as sorbic acid and acetic acid, are used in many low pH foods to prevent spoilage by fungi. The spoilage yeast Zygosaccharomyces bailii is notorious for its extreme resistance to preservatives and ability to grow in excess of legally-permitted concentrations of preservatives. Extreme resistance was confirmed in 38 strains of Z. bailii to several weak-acid preservatives. Using the brewing yeast Saccharomyces cerevisiae as a control, tests showed that Z. bailii was ~ 3-fold more resistant to a variety of weak-acids but was not more resistant to alcohols, aldehydes, esters, ethers, ketones, or hydrophilic chelating acids. The weak acids were chemically very diverse in structure, making it improbable that the universal resistance was caused by degradation or metabolism. Examination of Z. bailii cell populations showed that extreme resistance to sorbic acid, benzoic acid and acetic acid was limited to a few cells within the population, numbers decreasing with concentration of weak acid to < 1 in 1000. Re-inoculation of resistant sub-populations into weak-acid-containing media showed that all cells now possessed extreme resistance. Resistant sub-populations grown in any weak-acid preservative also showed ~ 100% cross-resistance to other weak-acid preservatives. Tests using 14C-acetic acid showed that weak-acid accumulation was much lower in the resistant sub-populations. Acid accumulation is caused by acid dissociation in the higher pH of the cytoplasm. Tests on intracellular pH (pHi) in the resistant sub-population showed that the pH was much lower, ~ pH 5.6, than in the sensitive bulk population. The hypothesis is proposed that extreme resistance to weak-acid preservatives in Z. bailii is due to population heterogeneity, with a small proportion of cells having a lower intracellular pH. This reduces the level of accumulation of any weak acid in the cytoplasm, thus conferring resistance to all weak acids, but not to other inhibitors

  1. Extreme resistance to weak-acid preservatives in the spoilage yeast Zygosaccharomyces bailii.

    PubMed

    Stratford, Malcolm; Steels, Hazel; Nebe-von-Caron, Gerhard; Novodvorska, Michaela; Hayer, Kimran; Archer, David B

    2013-08-16

    Weak-acid preservatives, such as sorbic acid and acetic acid, are used in many low pH foods to prevent spoilage by fungi. The spoilage yeast Zygosaccharomyces bailii is notorious for its extreme resistance to preservatives and ability to grow in excess of legally-permitted concentrations of preservatives. Extreme resistance was confirmed in 38 strains of Z. bailii to several weak-acid preservatives. Using the brewing yeast Saccharomyces cerevisiae as a control, tests showed that Z. bailii was ~3-fold more resistant to a variety of weak-acids but was not more resistant to alcohols, aldehydes, esters, ethers, ketones, or hydrophilic chelating acids. The weak acids were chemically very diverse in structure, making it improbable that the universal resistance was caused by degradation or metabolism. Examination of Z. bailii cell populations showed that extreme resistance to sorbic acid, benzoic acid and acetic acid was limited to a few cells within the population, numbers decreasing with concentration of weak acid to <1 in 1000. Re-inoculation of resistant sub-populations into weak-acid-containing media showed that all cells now possessed extreme resistance. Resistant sub-populations grown in any weak-acid preservative also showed ~100% cross-resistance to other weak-acid preservatives. Tests using (14)C-acetic acid showed that weak-acid accumulation was much lower in the resistant sub-populations. Acid accumulation is caused by acid dissociation in the higher pH of the cytoplasm. Tests on intracellular pH (pHi) in the resistant sub-population showed that the pH was much lower, ~ pH5.6, than in the sensitive bulk population. The hypothesis is proposed that extreme resistance to weak-acid preservatives in Z. bailii is due to population heterogeneity, with a small proportion of cells having a lower intracellular pH. This reduces the level of accumulation of any weak acid in the cytoplasm, thus conferring resistance to all weak acids, but not to other inhibitors.

  2. Breads Fortified with Freeze-Dried Vegetables: Quality and Nutritional Attributes. Part II: Breads Not Containing Oil as an Ingredient

    PubMed Central

    Ranawana, Viren; Campbell, Fiona; Bestwick, Charles; Nicol, Phyllis; Milne, Lesley; Duthie, Garry; Raikos, Vassilios

    2016-01-01

    The present article describes the second part of a study investigating the effect of adding vegetables on the nutritional, physico-chemical, and oxidative properties of wheat bread, and specifically focuses on bread that does not contain oil as an added ingredient. Wheat flour breads fortified with freeze-dried carrot, tomato, beetroot or broccoli were developed and assessed for their nutritional composition, antioxidant potential, oxidative stability, and storage properties. Using a simulated in vitro model, the study also examined the impact of vegetable addition on the oxidative stability of macronutrients during gastro-intestinal digestion. Adding vegetables improved the nutritional and functional attributes of the oil-free breads. However, they demonstrated a lower antioxidant potential compared to their oil-containing counterparts. Similarly, the textural and storage properties of the oil-free vegetable breads were poorer compared to the oil-containing breads. As expected, in the absence of oil the oil-free breads were associated with lower lipid oxidation both in their fresh form and during gastro-intestinal digestion. Adding vegetables reduced protein oxidation in the fresh oil-free breads but had no effect during gastro-intestinal digestion. The impact of vegetables on macronutrient oxidation in the oil-free breads during digestion appears to be vegetable-specific with broccoli exacerbating it and the others having no effect. Of the evaluated vegetables, beetroot showed the most promising nutritional and physico-chemical benefits when incorporated into bread that does not contain added oil. PMID:28231157

  3. Utilization of enzyme mixtures to retard bread crumb firming.

    PubMed

    León, Alberto E; Durán, Encarna; Benedito De Barber, Carmen

    2002-03-13

    The influence of enzyme mixtures containing amylase and lipase activities on straight dough bread staling was studied. Amylopectin retrogradation, crumb firming, amylose-lipid complexes, and dextrin production were analyzed in bread samples supplemented with two enzyme mixtures. The addition of enzyme mixtures to bread formula causes a beneficial effect on bread keeping properties and the formation of a more thermostable amylose-lipid complex than the one found in control bread. Amylopectin retrogradation was inhibited by the use of the enzyme; the effect was accompanied by reduced crumb-firming rates. The enzymatically generated water-soluble dextrins (maltose and DP3, DP4, DP5, and DP6 dextrins) are the most effective in preserving crumb softness during bread storage.

  4. Kinetics of the crust thickness development of bread during baking.

    PubMed

    Soleimani Pour-Damanab, Alireza; Jafary, A; Rafiee, Sh

    2014-11-01

    The development of crust thickness of bread during baking is an important aspect of bread quality and shelf-life. Computer vision system was used for measuring the crust thickness via colorimetric properties of bread surface during baking process. Crust thickness had a negative and positive relationship with Lightness (L (*) ) and total color change (E (*) ) of bread surface, respectively. A linear negative trend was found between crust thickness and moisture ratio of bread samples. A simple mathematical model was proposed to predict the development of crust thickness of bread during baking, where the crust thickness was depended on moisture ratio that was described by the Page moisture losing model. The independent variables of the model were baking conditions, i.e. oven temperature and air velocity, and baking time. Consequently, the proposed model had well prediction ability, as the mean absolute estimation error of the model was 7.93 %.

  5. Draft Genome Sequence of the Beer Spoilage Bacterium Megasphaera cerevisiae Strain PAT 1T

    PubMed Central

    Kutumbaka, Kirthi K.; Pasmowitz, Joshua; Mategko, James; Reyes, Dindo; Friedrich, Alex; Han, Sukkyun; Martens-Habbena, Willm; Neal-McKinney, Jason; Janagama, Harish K.; Nadala, Cesar

    2015-01-01

    The genus Megasphaera harbors important spoilage organisms that cause beer spoilage by producing off flavors, undesirable aroma, and turbidity. Megasphaera cerevisiae is mainly found in nonpasteurized low-alcohol beer. In this study, we report the draft genome of the type strain of the genus, M. cerevisiae strain PAT 1T. PMID:26358606

  6. Metabolic footprinting of Lactobacillus buchneri strain LA1147 during anaerobic spoilage of fermented cucumbers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lactobacillus buchneri has recently been associated with anaerobic spoilage of fermented cucumbers due to its ability to metabolize lactic acid into acetic acid and 1,2-propanediol. However, we have limited knowledge of other chemical components in fermented cucumber that may be related to spoilage ...

  7. Characteristics of Spoilage-Associated Secondary Cucumber Fermentation

    PubMed Central

    Franco, Wendy; Johanningsmeier, Suzanne D.; McFeeters, Roger F.

    2012-01-01

    Secondary fermentations during the bulk storage of fermented cucumbers can result in spoilage that causes a total loss of the fermented product, at an estimated cost of $6,000 to $15,000 per affected tank. Previous research has suggested that such fermentations are the result of microbiological utilization of lactic acid and the formation of acetic, butyric, and propionic acids. The objectives of this study were to characterize the chemical and environmental conditions associated with secondary cucumber fermentations and to isolate and characterize potential causative microorganisms. Both commercial spoilage samples and laboratory-reproduced secondary fermentations were evaluated. Potential causative agents were isolated based on morphological characteristics. Two yeasts, Pichia manshurica and Issatchenkia occidentalis, were identified and detected most commonly concomitantly with lactic acid utilization. In the presence of oxygen, yeast metabolic activities lead to lactic acid degradation, a small decline in the redox potential (Eh, Ag/AgCl, 3 M KCl) of the fermentation brines, and an increase in pH to levels at which bacteria other than the lactic acid bacteria responsible for the primary fermentation can grow and produce acetic, butyric, and propionic acids. Inhibition of these yeasts by allyl isothiocyanate (AITC) resulted in stabilization of the fermented medium, while the absence of the preservative resulted in the disappearance of lactic and acetic acids in a model system. Additionally, three Gram-positive bacteria, Lactobacillus buchneri, a Clostridium sp., and Pediococcus ethanolidurans, were identified as potentially relevant to different stages of the secondary fermentation. The unique opportunity to study commercial spoilage samples generated a better understanding of the microbiota and environmental conditions associated with secondary cucumber fermentations. PMID:22179234

  8. Viability and heat resistance of murine norovirus on bread.

    PubMed

    Takahashi, Michiko; Takahashi, Hajime; Kuda, Takashi; Kimura, Bon

    2016-01-04

    Contaminated bread was the cause of a large-scale outbreak of norovirus disease in Japan in 2014. Contamination of seafood and uncooked food products by norovirus has been reported several times in the past; however the outbreak resulting from the contamination of bread products was unusual. A few reports on the presence of norovirus on bread products are available; however there have been no studies on the viability and heat resistance of norovirus on breads, which were investigated in this study. ce:italic>/ce:italic> strain 1 (MNV-1), a surrogate for human norovirus, was inoculated directly on 3 types of bread, but the infectivity of MNV-1 on bread samples was almost unchanged after 5days at 20°C. MNV-1 was inoculated on white bread that was subsequently heated in a toaster for a maximum of 2min. The results showed that MNV-1 remained viable if the heating period was insufficient to inactivate. In addition, bread dough contaminated with MNV-1 was baked in the oven. Our results indicated that MNV-1 may remain viable on breads if the heating duration or temperature is insufficient.

  9. Characterization by volatile compounds of microbial deep spoilage in Iberian dry-cured ham.

    PubMed

    Martín, Alberto; Benito, María J; Aranda, Emilio; Ruiz-Moyano, Santiago; Córdoba, Juan J; Córdoba, María G

    2010-08-01

    In the present study, volatile compounds of spoiled dry-cured Iberian ham with deep spoilage or "bone taint" were analyzed and correlated with level of spoilage and the microorganisms detected. Volatile compounds extracted by a solid phase micro-extraction technique were assayed by gas chromatography/mass spectrometry. The spoiled hams were evaluated sensorially, and the correlations among volatile compounds, spoilage level, and microbial counts were studied. The spoiled hams had higher concentrations of hydrocarbons, alcohols, acids, esters, pyrazines, sulfur compounds, and other minor volatile compounds than unspoiled hams. The sensorial analysis showed that the spoilage level of hams correlated with several volatile compounds, most of them associated with Gram-positive catalase positive cocci and Enterobacteriaceae counts. Cyclic compounds such as cyclohexanone, some ethers, and pyrazines should be considered as indicators to monitor incipient microbial deep spoilage in the elaboration of this meat product.

  10. The impact of baking time and bread storage temperature on bread crumb properties.

    PubMed

    Bosmans, Geertrui M; Lagrain, Bert; Fierens, Ellen; Delcour, Jan A

    2013-12-15

    Two baking times (9 and 24 min) and storage temperatures (4 and 25 °C) were used to explore the impact of heat exposure during bread baking and subsequent storage on amylopectin retrogradation, water mobility, and bread crumb firming. Shorter baking resulted in less retrogradation, a less extended starch network and smaller changes in crumb firmness and elasticity. A lower storage temperature resulted in faster retrogradation, a more rigid starch network with more water inclusion and larger changes in crumb firmness and elasticity. Crumb to crust moisture migration was lower for breads baked shorter and stored at lower temperature, resulting in better plasticized biopolymer networks in crumb. Network stiffening, therefore, contributed less to crumb firmness. A negative relation was found between proton mobilities of water and biopolymers in the crumb gel network and crumb firmness. The slope of this linear function was indicative for the strength of the starch network.

  11. A prototype sensor system for the early detection of microbially linked spoilage in stored wheat grain

    NASA Astrophysics Data System (ADS)

    de Lacy Costello, B. P. J.; Ewen, R. J.; Gunson, H.; Ratcliffe, N. M.; Sivanand, P. S.; Spencer-Phillips, P. T. N.

    2003-04-01

    Sensors based on composites of metal oxides were fabricated and tested extensively under high-humidity and high-flow conditions with exposure to vapours reported to increase in the headspace of wheat grain (Triticum aestivum cv Hereward) colonized by fungi. The sensors that exhibited high sensitivity to target vapours combined with high stability were selected for inclusion into a four-sensor array prototype system. A sampling protocol aligned to parallel gas chromatography-mass spectrometry and human olfactory assessment studies was established for use with the sensor system. The sensor system was utilized to assess irradiated wheat samples that had been conditioned to 25% moisture content and inoculated with pathogens known to cause spoilage of grain in storage. These included the fungi Penicillium aurantiogriseum, Penicillium vulpinum, Penicillium verrucosum, Fusarium culmorum, Aspergillus niger, and Aspergillus flavus and the actinomycete, Streptomyces griseus. The sensor system successfully tracked the progress of the infections from a very early stage and the results were compared with human olfactory assessment panels run concurrently. A series of dilution studies were undertaken using previously infected grain mixed with sound grain, to improve the sensitivity and maximize the differentiation of the sensor system. An optimum set of conditions including incubation temperature, incubation time, sampling time, and flow rate were ascertained utilizing this method. The sensor system differentiated samples of sound grain from samples of sound grain with 1% (w/w) fungus infected grain added. Following laboratory trials, the prototype sensor system was evaluated in a commercial wheat grain intake facility. Thresholds calculated from laboratory tests were used to differentiate between sound and infected samples (classified by intake laboratory technicians) collected routinely from trucks delivering grain for use in food manufacture. All samples identified as having

  12. Molecular characterization of lactic acid populations associated with wine spoilage.

    PubMed

    Beneduce, L; Spano, G; Vernile, A; Tarantino, D; Massa, S

    2004-01-01

    We have investigated the prevalence of spoilage lactic acid bacteria (LAB) in table wines produced in the Apulia region. The occurrence of LAB was evaluated in wines produced with low sulphur dioxide doses and not supplemented with selected malolactic starters such as Oenococcus oeni. About 150 strains were isolated from wine must and a molecular characterization was performed using PCR-based techniques. Most of the strains analysed belonged to Lactobacillus plantarum species. However, some of the strains were identified as Pediococcus damnosus and Leuconostoc sp. The amplified fragments of Pediococcus damnosus were cloned and sequenced. The coding sequence was highly homologous to that of the ropy plasmid confirming that the isolated strain was a ropy(+) Pediococcus damnosus. In all the samples analysed, the final must pH value reached was relatively high (from 3.78 to 3.90). The high pH values had probably negatively influenced (counteracted) the activity of sulphur dioxide added, allowing proliferation of spoilage wine microorganisms.

  13. The influence of bacterial inoculants on the microbial ecology of aerobic spoilage of barley silage.

    PubMed

    Inglis, G D; Yanke, L J; Kawchuk, L M; McAllister, T A

    1999-01-01

    The aerobic decomposition of barley silage treated with two inoculants (LacA and LacB) containing mixtures of Lactobacillus plantarum and Enterococcus faecium was investigated over a 28-day period. Initially, yeast and bacterial populations were larger in silage inoculated with LacA than in silage treated with LacB or water alone (control). Differences in the succession of yeasts in silage treated with LacA were observed relative to the other two treatments. From silage treatment with LacA, Issatchenkia orientalis was the most prevalent yeast taxon over all of the sample times, and the filamentous fungus Microascus brevicaulis was also frequently isolated at later sample dates (> or = 14 days). In contrast, Saccharomyces exiguus was the most prominent yeast recovered from silage treated with LacB and water alone on days 2 and 4, although it was supplanted by I. orientalis at later sample times. Successional trends of bacteria were similar for all three treatments. Lactobacillus spp. were initially the most prevalent bacteria isolated, followed by Bacillus spp. (primarily Bacillus pumilus). However, the onset of Bacillus spp. prominence was faster in LacA silage, and Klebsiella planticola was frequently recovered at later sample times (> or = 14 days). More filamentous fungi were recovered from LacA silage on media containing carboxylmethylcellulose, pectin, or xylan. The most commonly isolated taxa were Absidia sp., Aspergillus flavus, Aspergillus fumigatus, Byssochlamys nivea, Monascus ruber, Penicillium brevicompactum, Pseudoallescheria boydii, and M. brevicaulis. The results of this study indicated that the two bacterial inoculants incorporated into barley at the time of ensilage affected the microbial ecology of silage decomposition following exposure to air. However, neither of the microbial inoculants effectively delayed aerobic spoilage of barley silage, and the rate of decomposition of silage treated with one of the inoculants (LacA) was actually enhanced.

  14. Synergized antimicrobial activity of eugenol incorporated polyhydroxybutyrate films against food spoilage microorganisms in conjunction with pediocin.

    PubMed

    Narayanan, Aarthi; Neera; Mallesha; Ramana, Karna Venkata

    2013-07-01

    Biopolymers and biopreservatives produced by microorganisms play an essential role in food technology. Polyhydroxyalkanoates and bacteriocins produced by bacteria are promising components to safeguard the environment and for food preservation applications. Polyhydroxybutyrate (PHB)-based antimicrobial films were prepared incorporating eugenol, from 10 to 200 μg/g of PHB. The films were evaluated for antimicrobial activity against foodborne pathogens, spoilage bacteria, and fungi such as Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Bacillus cereus, Aspergillus flavus, Aspergillus niger, Penicillium sp., and Rhizopus sp. The synergistic antimicrobial activity of the films in the presence of crude pediocin was also investigated. The broth system containing pediocin (soluble form) as well as antimicrobial PHB film demonstrated an extended lag phase and a significant growth reduction at the end of 24 h against the bacteria. Crude pediocin alone could not elicit antifungal activity, while inhibition of growth and sporulation were observed in the presence of antimicrobial PHB film containing eugenol (80 μg/g) until 7 days in the case of molds, i.e., A. niger, A. flavus, Penicillium sp., and Rhizopus sp. in potato dextrose broth. In the present study, we identified that use of pediocin containing broth in conjunction with eugenol incorporated PHB film could function in synergized form, providing effective hurdle toward food contaminating microorganisms. Furthermore, tensile strength, percent crystallinity, melting point, percent elongation to break, glass transition temperature, and seal strength of the PHB film with and without eugenol incorporation were investigated. The migration of eugenol on exposure to different liquid food simulants was also analyzed using Fourier transform infrared spectroscopy. The study is expected to provide applications for pediocin in conjunction with eugenol containing PHB film to enhance the shelf life of foods in the

  15. RICE BREAD QUALITY AS AFFECTED BY YEAST AND BRAN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whole rice bread (WRB) has been developed in our laboratory for people suffering from Celiac disease and other food allergies. The WRB has texture and related qualities comparable with white or whole wheat breads. This paper reports the results of three levels of yeast, defatted rice bran on the t...

  16. Bread Loaf Rural Teacher Network: A Portable Community.

    ERIC Educational Resources Information Center

    Active Learner: A Foxfire Journal for Teachers, 1998

    1998-01-01

    The experiences of two teachers describe how BreadNet, an online professional-development and educational conference, enables teachers with similar interests to work together and maintain a sense of community. BreadNet allowed their rural schools to participate in projects with distant schools, leading to improvements in the quantity and quality…

  17. Optimization of taro mucilage and fat levels in sliced breads.

    PubMed

    Nagata, Carina Lumie Pereira; Andrade, Luan Alberto; Pereira, Joelma

    2015-09-01

    Bread is one of the most commonly consumed foods, and much ongoing research is aimed at meeting the demand for higher quality bread products in terms of greater volume and softness with characteristic flavor, aroma and color. The goal of the present study was to optimize the amounts of lyophilized taro mucilage and hydrogenated vegetable fat added to sliced bread formulations to improve the physical characteristics of the bread while reducing lipid levels and maintaining good sensorial quality. For the analysis, a central composite rotatable design (CCRD) was used for the two factors, resulting in 11 total experiments. Physical, chemical, and sensory analyses were performed. Breads containing taro mucilage were soft and exhibited good sensorial quality. Optimal amounts of the two factors studied were determined using response surface methodology to produce breads with greater specific volume, higher bread-making quality, and lower fat levels than current formulations. The optimal levels of lyophilized taro mucilage and hydrogenated vegetable fat in the sliced bread formulation were 0.73 g 100 g(-1) and 1.58 g 100 g(-1), respectively.

  18. Characterization of Sterol Oxidation Products in Two Breaded Shrimp Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two breaded shrimp products were examined for the changes in cholesterol, phytosterols, and fatty acids that occurred during cooking. The products were analyzed by gas chromatography (GC) in the raw, baked, and fried states after separation into breading and shrimp components. Cholesterol, campest...

  19. Panis populi--bread and public health in Australia.

    PubMed

    Pearn, J

    1998-04-01

    The 'standard loaf, 680 gm, white, supermarket-purchased' as expressed in the Consumer Price Index, is but the basic form of bread sold to the Australian public. In the public health context, three themes have been intimately associated with bread--quality control, price control and bread used as a vehicle for supplementary nutritive agents important in preventive medicine. Price control, through assizing, has been a feature of bread marketing in western communities for seven centuries; and bread remains the last item on which price control (although seldom enforced) exists in Australia. Quality control, for public health, is determined both by regulation and by the force of increasingly literate consumers, of whom women occupy the most important determinant. From the preventive medicine point of view, important themes in bread quality, such as its use to reduce laxative sales on the one hand and to reduce the demographic incidence of colonic cancer on the other, remains outside formal regulation. Australia is a relatively conservative nation in the context of nutritional additives. It was not until 1953 that the National Health and Medical Research Council approved the addition of extra B vitamins to bread. Currently, folic acid is added as a discretion to selected high-premium breakfast cereals in Australia in one attempt to reduce the incidence to neural tube defects. The addition of such ingredients to bread remains an unrealised, but potentially important aspect of preventive medicine in Australia.

  20. 21 CFR 102.55 - Nonstandardized breaded composite shrimp units.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Nonstandardized breaded composite shrimp units... for Specific Nonstandardized Foods § 102.55 Nonstandardized breaded composite shrimp units. (a) The... described by § 161.175(c)(6) of this chapter, except that the food is made from comminuted shrimp and is...

  1. 21 CFR 102.55 - Nonstandardized breaded composite shrimp units.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Nonstandardized breaded composite shrimp units... for Specific Nonstandardized Foods § 102.55 Nonstandardized breaded composite shrimp units. (a) The... described by § 161.175(c)(6) of this chapter, except that the food is made from comminuted shrimp and is...

  2. 21 CFR 102.55 - Nonstandardized breaded composite shrimp units.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Nonstandardized breaded composite shrimp units... for Specific Nonstandardized Foods § 102.55 Nonstandardized breaded composite shrimp units. (a) The... described by § 161.175(c)(6) of this chapter, except that the food is made from comminuted shrimp and is...

  3. 21 CFR 102.55 - Nonstandardized breaded composite shrimp units.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Nonstandardized breaded composite shrimp units... for Specific Nonstandardized Foods § 102.55 Nonstandardized breaded composite shrimp units. (a) The... described by § 161.175(c)(6) of this chapter, except that the food is made from comminuted shrimp and is...

  4. Composition and Palatability of Breads Made with Ground Soybean Products.

    ERIC Educational Resources Information Center

    Klein, Barbara P.; And Others

    1980-01-01

    Ground soy products made from whole soybeans were used in bread as substitutes for 12 percent of the wheat flour to demonstrate that home-prepared soy products can be used to bake palatable breads and supplement their protein content. (Author/SK)

  5. 21 CFR 102.55 - Nonstandardized breaded composite shrimp units.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... largest type used in the words “breaded shrimp sticks” or the other comparable words required by this... for Specific Nonstandardized Foods § 102.55 Nonstandardized breaded composite shrimp units. (a) The common on usual name of the food product that conforms to the definition and standard of...

  6. Contamination profiles and characterisation of Bacillus species in wheat bread and raw materials for bread production.

    PubMed

    Rosenkvist, H; Hansen, A

    1995-08-01

    The Bacillus counts in white and wholemeal wheat loaves produced without preservatives or sour dough were consistently 10(6) cfu/g after two days of storage at ambient summer temperatures (25-30 degree C). Identified species were B. subtilis (70%), B. licheniformis (24%), B. pumilus (2%) and B. cereus (2%). The dominance of B. subtilis in bread could be explained by the higher resistance to heat of this species as determined by inoculation studies. Among 14 species isolated from retail bread and wheat grains, B. subtilis was the only species associated with ropiness. Samples of raw materials, particularly bran, seeds and oat products, contained low levels (10(0) - 10(2) cfu/g) of Bacillus spores, surviving a heat treatment (100 degree C, 10 min) corresponding to a baking process. Even low spore levels in raw materials with the frequently isolated species, B. licheniformis (49%) and B. subtilis (10%), resulted in 10(7) Bacillus per g bread crumb in two days as determined by test bakings. The results indicate a need for controlling growth of Bacillus in bread.

  7. The information presented on labels for bread produced in Latvia.

    PubMed

    Murniece, Irisa; Straumite, Evita

    2014-11-01

    Bakery products, particularly bread, make up a significant share of the food guide pyramid. To help consumers make more informed choices from the bread available in the market, it is essential to provide correct and appropriate information on food labels. The aim of this research was to analyse the information shown on labels for different types of bread produced in Latvia. Different types of bread were chosen from 28 bakeries located in regions throughout Latvia. For statistical analysis, the data were processed using the S-PLUS 6.1 Professional Edition. From the analysis of labels on bread in Latvian, we conclude there is an absence of information about energy; only 4.8% of labels presented energy calculated according to the Nutritional Labelling Regulation 90/496/ECC.

  8. 21 CFR 136.180 - Whole wheat bread, rolls, and buns.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... statement of ingredients prescribed for bread, rolls and buns by § 136.110, except that: (1) The dough is... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Whole wheat bread, rolls, and buns. 136.180... § 136.180 Whole wheat bread, rolls, and buns. (a) Each of the foods whole wheat bread, graham...

  9. 21 CFR 136.180 - Whole wheat bread, rolls, and buns.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... statement of ingredients prescribed for bread, rolls and buns by § 136.110, except that: (1) The dough is... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Whole wheat bread, rolls, and buns. 136.180... § 136.180 Whole wheat bread, rolls, and buns. (a) Each of the foods whole wheat bread, graham...

  10. Lactic acid bacteria and their controversial role in fresh meat spoilage.

    PubMed

    Pothakos, Vasileios; Devlieghere, Frank; Villani, Francesco; Björkroth, Johanna; Ercolini, Danilo

    2015-11-01

    Lactic acid bacteria (LAB) constitute a heterogeneous group that has been widely associated with fresh meat and cooked meat products. They represent a controversial cohort of microbial species that either contribute to spoilage through generation of offensive metabolites and the subsequent organoleptic downgrading of meat or serve as bioprotective agents with strains of certain species causing unperceivable or no alterations. Therefore, significant distinction among biotypes is substantiated by studies determining spoilage potential as a strain-specific trait corroborating the need to revisit the concept of spoilage.

  11. Advances in the control of wine spoilage by Zygosaccharomyces and Dekkera/Brettanomyces.

    PubMed

    Zuehlke, J M; Petrova, B; Edwards, C G

    2013-01-01

    Understanding the characteristics of yeast spoilage, as well as the available control technologies, is vital to producing consistent, high-quality wine. Zygosaccharomyces bailii contamination may result in refermentation and CO2 production in sweet wines or grape juice concentrate, whereas Brettanomyces bruxellensis spoilage often contributes off-odors and flavors to red wines. Early detection of these yeasts by selective/differential media or genetic methods is important to minimize potential spoilage. More established methods of microbial control include sulfur dioxide, dimethyl dicarbonate, and filtration. Current research is focused on the use of chitosan, pulsed electric fields, low electric current, and ultrasonics as means to protect wine quality.

  12. Antifungal Activity of Wickerhamomyces anomalus and Lactobacillus plantarum during Sourdough Fermentation: Identification of Novel Compounds and Long-Term Effect during Storage of Wheat Bread

    PubMed Central

    Coda, Rossana; Cassone, Angela; Rizzello, Carlo G.; Nionelli, Luana; Cardinali, Gianluigi; Gobbetti, Marco

    2011-01-01

    This study aimed at investigating the antifungal activity of Wickerhamomyces anomalus and sourdough lactic acid bacteria to extend the shelf life of wheat flour bread. The antifungal activity was assayed by agar diffusion, growth rate inhibition, and conidial germination assays, using Penicillium roqueforti DPPMAF1 as the indicator fungus. Sourdough fermented by Lactobacillus plantarum 1A7 (S1A7) and dough fermented by W. anomalus LCF1695 (D1695) were selected and characterized. The water/salt-soluble extract of S1A7 was partially purified, and several novel antifungal peptides, encrypted into sequences of Oryza sativa proteins, were identified. The water/salt-soluble extract of D1695 contained ethanol and, especially, ethyl acetate as inhibitory compounds. As shown by growth inhibition assays, both water/salt-soluble extracts had a large inhibitory spectrum, with some differences, toward the most common fungi isolated from bakeries. Bread making at a pilot plant was carried out with S1A7, D1695, or a sourdough started with a combination of both strains (S1A7-1695). Slices of the bread manufactured with S1A7-1695 did not show contamination by fungi until 28 days of storage in polyethylene bags at room temperature, a level of protection comparable to that afforded by 0.3% (wt/wt) calcium propionate. The effect of sourdough fermentation with W. anomalus LCF1695 was also assessed based on rheology and sensory properties. PMID:21441340

  13. Antifungal activity of Wickerhamomyces anomalus and Lactobacillus plantarum during sourdough fermentation: identification of novel compounds and long-term effect during storage of wheat bread.

    PubMed

    Coda, Rossana; Cassone, Angela; Rizzello, Carlo G; Nionelli, Luana; Cardinali, Gianluigi; Gobbetti, Marco

    2011-05-01

    This study aimed at investigating the antifungal activity of Wickerhamomyces anomalus and sourdough lactic acid bacteria to extend the shelf life of wheat flour bread. The antifungal activity was assayed by agar diffusion, growth rate inhibition, and conidial germination assays, using Penicillium roqueforti DPPMAF1 as the indicator fungus. Sourdough fermented by Lactobacillus plantarum 1A7 (S1A7) and dough fermented by W. anomalus LCF1695 (D1695) were selected and characterized. The water/salt-soluble extract of S1A7 was partially purified, and several novel antifungal peptides, encrypted into sequences of Oryza sativa proteins, were identified. The water/salt-soluble extract of D1695 contained ethanol and, especially, ethyl acetate as inhibitory compounds. As shown by growth inhibition assays, both water/salt-soluble extracts had a large inhibitory spectrum, with some differences, toward the most common fungi isolated from bakeries. Bread making at a pilot plant was carried out with S1A7, D1695, or a sourdough started with a combination of both strains (S1A7-1695). Slices of the bread manufactured with S1A7-1695 did not show contamination by fungi until 28 days of storage in polyethylene bags at room temperature, a level of protection comparable to that afforded by 0.3% (wt/wt) calcium propionate. The effect of sourdough fermentation with W. anomalus LCF1695 was also assessed based on rheology and sensory properties.

  14. Baking the first bread in space

    NASA Technical Reports Server (NTRS)

    1987-01-01

    This Getaway Special program is a joint venture between Spar, Monarch flour and Telesat, with Telesat being responsible for the design, manufacture and implementation of the equipment. The purpose of the experiment is to investigate the behavior of bread yeast in the absence of gravity and in the presence of normal atmospheric pressure. The proposed design mixes flour, water and yeast on-orbit, allows the mixture to prove and then bakes it. This paper outlines the development history of the experiment, the various test programs and some of the problems encountered, with their solutions.

  15. In Vitro Bioaccessibility of Phenolic Acids from a Commercial Aleurone-Enriched Bread Compared to a Whole Grain Bread.

    PubMed

    Dall'Asta, Margherita; Bresciani, Letizia; Calani, Luca; Cossu, Marta; Martini, Daniela; Melegari, Camilla; Del Rio, Daniele; Pellegrini, Nicoletta; Brighenti, Furio; Scazzina, Francesca

    2016-01-13

    Wheat aleurone, due to its potentially higher bioaccessibility and bioavailability of micronutrients and phenolic acids, could represent a useful ingredient in the production of commonly consumed cereal-based food. The aim of the present study was to investigate the in vitro bioaccessibility of phenolic acids both from an aleurone-enriched bread and from a whole grain bread. The two bread samples were firstly characterized for the phenolic acid content. An in vitro digestion was then performed in order to evaluate the release of phenolic acids. The results obtained suggest that the bioaccessibility of the phenolic acids in the aleurone-enriched bread is higher than in the whole grain bread. These in vitro results suggest the potential use of aleurone in the production of foods, and this may represent an attractive possibility to vehicle nutritionally interesting components to consumers.

  16. In Vitro Bioaccessibility of Phenolic Acids from a Commercial Aleurone-Enriched Bread Compared to a Whole Grain Bread

    PubMed Central

    Dall’Asta, Margherita; Bresciani, Letizia; Calani, Luca; Cossu, Marta; Martini, Daniela; Melegari, Camilla; Del Rio, Daniele; Pellegrini, Nicoletta; Brighenti, Furio; Scazzina, Francesca

    2016-01-01

    Wheat aleurone, due to its potentially higher bioaccessibility and bioavailability of micronutrients and phenolic acids, could represent a useful ingredient in the production of commonly consumed cereal-based food. The aim of the present study was to investigate the in vitro bioaccessibility of phenolic acids both from an aleurone-enriched bread and from a whole grain bread. The two bread samples were firstly characterized for the phenolic acid content. An in vitro digestion was then performed in order to evaluate the release of phenolic acids. The results obtained suggest that the bioaccessibility of the phenolic acids in the aleurone-enriched bread is higher than in the whole grain bread. These in vitro results suggest the potential use of aleurone in the production of foods, and this may represent an attractive possibility to vehicle nutritionally interesting components to consumers. PMID:26771635

  17. Genomic Encyclopedia of Fungi

    SciTech Connect

    Grigoriev, Igor

    2012-08-10

    Genomes of fungi relevant to energy and environment are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 150 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such parts suggested by comparative genomics and functional analysis in these areas are presented here.

  18. Moisture distribution during conventional or electrical resistance oven baking of bread dough and subsequent storage.

    PubMed

    Derde, Liesbeth J; Gomand, Sara V; Courtin, Christophe M; Delcour, Jan A

    2014-07-09

    Electrical resistance oven (ERO) baking processes bread dough with little temperature gradient in the baking dough. Heating of the dough by means of an ERO is based on the principles of Joule's first law and Ohm's law. This study compared the changes in moisture distribution and physical changes in starch of breads conventionally baked or using an ERO. The moisture contents in fresh ERO breads are generally lower than those in conventional breads. During storage of conventionally baked breads, water migrates from the crumb to the crust and moisture contents decrease throughout the bread crumb. Evidently, less moisture redistribution occurs in ERO breads. Also, the protons of ERO bread constituents were less mobile than their counterparts in conventional bread. Starch retrogradation occurs to similar extents in conventional and ERO bread. As a result, the changes in proton mobility cannot be attributed to differences in levels of retrograded starch and seem to be primarily determined by the overall lower moisture content.

  19. Co-ingestion of essence of chicken to moderate glycaemic response of bread.

    PubMed

    Sun, Lijuan; Wei Jie Tan, Kevin; Jeyakumar Henry, Christiani

    2015-01-01

    Essence of chicken (EOC) beverage is a chicken meat extract, widely consumed in Asian countries for health benefits. EOC is a rich source of peptides and amino acids. White bread has become a popular staple food in all regions of Southeast Asia. A randomized controlled, crossover, non-blind trial was performed to investigate the role of EOC on glycaemic response (GR) of white bread. Ten healthy young subjects returned on five separate days for three glucose and two bread sessions. Subjects consumed bread or bread with EOC. The 120 min incremental area under the curve was significantly lower after consuming two bottles of EOC with bread than white bread alone. The glycaemic index (GI) of white bread was 83 and white bread with EOC 57. The co-ingestion of EOC may be a practical and simple way to reduce the GR of bread and other starch-based staples.

  20. Baking quality, sensory properties and shelf life of bread with polyols.

    PubMed

    Bhise, Suresh; Kaur, A

    2014-09-01

    The polyols namely glycerol, sorbitol and mannitol were incorporated at 2, 4 and 6 % level in flour for bread making and their effect on textural properties, bread making quality and sensory acceptability of bread was studied. The effect of incorporation revealed the increased bake absorption, bread weight and decreased specific volume. The overall acceptability scores were maximum for bread prepared with glycerol at 2 % level, followed by sorbitol at 4 % level and mannitol at 4 % level. During storage of packed bread, moisture content and water activity were higher for bread prepared from polyols as compared to control and it was observed that moisture content was higher in bread packed in Polypropylene. Formation of free fatty acid content (% oleic acid) was observed to be higher in the breads stored at ambient condition and packed in Low density polyethylene packaging material. The overall acceptability of bread decreased with the increased storage period.

  1. Antioxidant contents and antioxidative properties of traditional rye breads.

    PubMed

    Michalska, Anna; Ceglinska, Alicja; Amarowicz, Ryszard; Piskula, Mariusz Konrad; Szawara-Nowak, Dorota; Zielinski, Henryk

    2007-02-07

    The purpose of this research was to find out the effect of flour extraction rate on the antioxidative properties of traditional rye bread and then to compare the bioactive compounds content and antioxidant properties of rye breads with commercial wheat roll. Four types of rye flour with different extraction rates of 100 (whole meal dark flour), 95 (brown flour), 90 (brown flour), and 70% (light flour) originated from Warko rye cultivar were used for traditional bread baking with sourdough fermentation. Four types of the respective rye breads were analyzed for their potentially beneficial components, including tocopherols and tocotrienols, total phenolics and flavonoids, reduced glutathione, and inositol hexaphosphates. Moreover, the phenolic acids profile was provided. The Trolox equivalent antioxidant capacity (TEAC) of the breads was evaluated using free radical scavenging activities of 80% methanol extracts against ABTS*+ radical cation (ABTS radical cation decolorization method) whereas radical scavenging activity (RSA) was determined against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH*). The superoxide dismutase-like activity (SOD-like activity) was evaluated as free radical scavenging activities of PBS extracts against superoxide anion radicals (O2*-). The results were compared to whole meal rye bread as well as to wheat roll taken as representative example of wheat based bakery product. The studies showed that flour extraction rates strongly affected the content of bioactive compounds and antioxidative properties of traditionally baked rye breads. The incorporation of the rye flours with extraction rates from 100 down to 70% in the formulation caused decrease in tocopherol (T), tocotrienol (T3), inositol hexaphosphate (IP6), and phenolic compound (TPC) contents in rye breads. No changes in reduced glutathione (GSH) contents were noted between each type of rye bread. A significant decrease in Trolox equivalent antioxidant capacity and radical DDPH scavenging

  2. Development of a colorimetric sensor array for squid spoilage assessment.

    PubMed

    Zaragozá, Patricia; Fuentes, Ana; Ruiz-Rico, María; Vivancos, José-Luis; Fernández-Segovia, Isabel; Ros-Lis, José V; Barat, José M; Martínez-Máñez, Ramón

    2015-05-15

    The aim of this work was to develop and evaluate a rapid, easy-to-use optoelectronic system for the shelf-life assessment of squid in cold storage. For this purpose, an optoelectronic nose was designed, which consisted of an array containing six sensing materials prepared by combining different dyes and two inorganic supports (aluminium oxide and silica gel). Samples were packaged with the colorimetric array and kept in cold storage for 12 days. Squid spoilage was monitored simultaneously by the colorimetric array and by the physico-chemical and microbial analyses during storage. Samples exceeded the acceptability limits for microbial counts on the third day. PCA analysis carried out with CIELab showed that the colorimetric array was able to discriminate between fresh squid fit for consumption and spoiled squid. The statistical models obtained by PLS, with the optoelectronic nose, successfully predicted CO2 and O2 content in the headspace as well as microbial growth.

  3. Clonal reproduction in fungi

    PubMed Central

    Taylor, John W.; Hann-Soden, Christopher; Branco, Sara; Sylvain, Iman; Ellison, Christopher E.

    2015-01-01

    Research over the past two decades shows that both recombination and clonality are likely to contribute to the reproduction of all fungi. This view of fungi is different from the historical and still commonly held view that a large fraction of fungi are exclusively clonal and that some fungi have been exclusively clonal for hundreds of millions of years. Here, we first will consider how these two historical views have changed. Then we will examine the impact on fungal research of the concept of restrained recombination [Tibayrenc M, Ayala FJ (2012) Proc Natl Acad Sci USA 109 (48):E3305–E3313]. Using animal and human pathogenic fungi, we examine extrinsic restraints on recombination associated with bottlenecks in genetic variation caused by geographic dispersal and extrinsic restraints caused by shifts in reproductive mode associated with either disease transmission or hybridization. Using species of the model yeast Saccharomyces and the model filamentous fungus Neurospora, we examine intrinsic restraints on recombination associated with mating systems that range from strictly clonal at one extreme to fully outbreeding at the other and those that lie between, including selfing and inbreeding. We also consider the effect of nomenclature on perception of reproductive mode and a means of comparing the relative impact of clonality and recombination on fungal populations. Last, we consider a recent hypothesis suggesting that fungi thought to have the most severe intrinsic constraints on recombination actually may have the fewest. PMID:26195774

  4. Water uptake mechanism in crispy bread crust.

    PubMed

    van Nieuwenhuijzen, Neleke H; Meinders, Marcel B J; Tromp, R Hans; Hamer, Rob J; van Vliet, Ton

    2008-08-13

    Crispness is an important quality characteristic of dry solid food products such as crispy rolls. Its retention is directly related to the kinetics of water uptake by the crust. In this study, a method for the evaluation of the water sorption kinetics in bread crust is proposed. Two different sorption experiments were used: an oscillatory sorption test and a sorption test in which the air relative humidity (RH) was increased stepwise. These two experiments had different time scales, which made it possible to get a better understanding of the mechanisms involved. Results show that the adsorption and desorption dynamics of the oscillatory sorption test could be described by a single exponential in time. The water uptake rate ( k) was one of the fitting parameters. A maximum in the water uptake rate was found for a RH value between 50 and 70%. The rate parameters of the experiment where RH was increased stepwise were around a factor 10 lower than those derived from oscillatory sorption experiments. This is an important factor when designing experiments for the determination of water uptake rates. In addition, also a parameter describing the time dependence of the rate parameters of the oscillatory sorption experiment was calculated (C), again by fitting a single exponential to the rate parameters. C was in the same range as the rate parameter of the isotherm experiment. This indicates that different (relaxation) processes are acting at the same time in the bread crust during water uptake.

  5. Lactobacilli and tartrazine as causative agents of red-color spoilage in cucumber pickle products.

    PubMed

    Pérez-Díaz, I M; Kelling, R E; Hale, S; Breidt, F; McFeeters, R F

    2007-09-01

    The cucumber pickling industry has sporadically experienced spoilage outbreaks in pickled cucumber products characterized by development of red color on the surface of the fruits. Lactobacillus casei and Lactobacillus paracasei were isolated from 2 outbreaks of this spoilage that occurred about 15 y apart during the last 3 decades. Both organisms were shown to produce this spoilage when inoculated into pickled cucumbers while concomitantly degrading the azo dye tartrazine (FD&C yellow nr 5). This food dye is used as a yellow coloring in the brine cover solutions of commercial pickled cucumber products. The red color does not occur in the absence of tartrazine, nor when turmeric is used as a yellow coloring in the pickles. Addition of sodium benzoate to the brine cover solutions of a pickled cucumber product, more specifically hamburger dill pickles, prevented growth of these lactic acid bacteria and the development of the red spoilage.

  6. Grape and apple wines volatile fermentation products and possible relation to spoilage.

    PubMed

    Polychroniadou, E; Kanellaki, M; Iconomopoulou, M; Koutinas, A A; Marchant, R; Banat, I M

    2003-05-01

    The main volatile by-products of the alcoholic fermentation of grape wine, cider and apple pulp wine were investigated to determine if any correlated with spoilage resistance in the latter two. Spoilage was visually detected after seven days in low-alcohol grape wine in comparison to 11 and 16 days in cider and apple pulp wine, respectively. Acetaldehyde, ethyl acetate, methanol, propanol, isobutanol and amyl alcohols were the main fermentation by-products detected in all three wines. There were highest concentrations of acetaldehyde, ethyl acetate, methanol and propanol in grape wine and, therefore, these by-products could not be implicated in spoilage resistance in apple wines. Increased concentrations of isobutanol and amyl alcohols, however, in cider and apple pulp wine in comparison to grape wine might have been the reason for spoilage resistance in the apple wines.

  7. Molecular Features of Wheat Endosperm Arabinoxylan Inclusion in Functional Bread

    PubMed Central

    Li, Weili; Hu, Hui; Wang, Qi; Brennan, Charles J.

    2013-01-01

    Arabinoxylan (AX) is a major dietary fibre component found in a variety of cereals. Numerous health benefits of arabinoxylans have been reported to be associated with their solubility and molecular features. The current study reports the development of a functional bread using a combination of AX-enriched material (AEM) and optimal commercial endoxylanase. The total AX content of bread was increased to 8.2 g per 100 g available carbohydrates. The extractability of AX in breads with and without endoxylanase was determined. The results demonstrate that water-extractable AX (WE-AX) increased progressively through the bread making process. The application of endoxylanase also increased WE-AX content. The presence of 360 ppm of endoxylanase had positive effects on the bread characteristics in terms of bread volume and firmness by converting the water unextractable (WU)-AX to WE-AX. In addition, the molecular weight (Mw) distribution of the WE-AX of bread with and without endoxylanase was characterized by size-exclusion chromatography. The results show that as the portion of WE-AX increased, the amount of high Mw WE-AX (higher than 100 kDa) decreased, whereas the amount of low Mw WE-AX (lower than 100 kDa) increased from 33.2% to 44.2% through the baking process. The low Mw WE-AX further increased to 75.5% with the application of the optimal endoxylanase (360 ppm). PMID:28239111

  8. 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-O2 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.

  9. Prevention of Yeast Spoilage in Feed and Food by the Yeast Mycocin HMK

    PubMed Central

    Lowes, K. F.; Shearman, C. A.; Payne, J.; MacKenzie, D.; Archer, D. B.; Merry, R. J.; Gasson, M. J.

    2000-01-01

    The yeast Williopsis mrakii produces a mycocin or yeast killer toxin designated HMK; this toxin exhibits high thermal stability, high pH stability, and a broad spectrum of activity against other yeasts. We describe construction of a synthetic gene for mycocin HMK and heterologous expression of this toxin in Aspergillus niger. Mycocin HMK was fused to a glucoamylase protein carrier, which resulted in secretion of biologically active mycocin into the culture media. A partial purification protocol was developed, and a comparison with native W. mrakii mycocin showed that the heterologously expressed mycocin had similar physiological properties and an almost identical spectrum of biological activity against a number of yeasts isolated from silage and yoghurt. Two food and feed production systems prone to yeast spoilage were used as models to assess the ability of mycocin HMK to act as a biocontrol agent. The onset of aerobic spoilage in mature maize silage was delayed by application of A. niger mycocin HMK on opening because the toxin inhibited growth of the indigenous spoilage yeasts. This helped maintain both higher lactic acid levels and a lower pH. In yoghurt spiked with dairy spoilage yeasts, A. niger mycocin HMK was active at all of the storage temperatures tested at which yeast growth occurred, and there was no resurgence of resistant yeasts. The higher the yeast growth rate, the more effective the killing action of the mycocin. Thus, mycocin HMK has potential applications in controlling both silage spoilage and yoghurt spoilage caused by yeasts. PMID:10698773

  10. The spoilage microflora of cured, cooked turkey breasts prepared commercially with or without smoking.

    PubMed

    Samelis, J; Kakouri, A; Rementzis, J

    2000-06-01

    Lactobacillus sakei subsp. carnosus was predominant in the spoilage flora of sliced, vacuum-packed, smoked, oven-cooked turkey breast fillets which developed mild, sour spoilage flavors after 4 weeks storage at 4 degrees C. In contrast, Leuconostoc mesenteroides subsp. mesenteroides predominated in the spoilage flora of sliced, vacuum-packed, unsmoked, boiled turkey breast fillets from the same plant which were also stored at 4 degrees C. The spoilage flora of the unsmoked breasts grew faster than that of the smoked breasts and was more diverse. Lactobacillus sakei, Weissella viridescens and an atypical group of leuconostoc-like bacteria were also members of the unsmoked turkey breasts flora. Consequently, the unsmoked breasts spoiled after 2 weeks at 4 degrees C: the packs swelled and the meat developed strong sour odors and flavors and abundant slime. Except for the unidentified leuconostocs, which apparently survived boiling of the unsmoked turkey, all the spoilage organisms contaminated the meats during the slicing and vacuum packaging operations. From their biochemical reactions and cellular fatty acid profiles, the atypical leuconostocs were more closely related to Leuconostoc carnosum than W. viridescens. Carnobacteria and Brochothrix thermosphacta were present in relatively large numbers on the raw turkey, but were not numerous in the spoilage flora of the cooked, vacuum-packed meat products.

  11. Of all foods bread is the most noble: Carl von Linné (Carl Linneaus) on bread1

    PubMed Central

    Räsänen, Leena

    2007-01-01

    Carl von Linné was interested in dietetics, which in his time covered all aspects of a healthy life. As a utilitarian he understood the importance of private economy and paid attention to bread in many of his publications. Two texts, Ceres noverca arctoum and De pane diaetetico, were wholly devoted to bread and bread-making. Linné classified different types of bread, and described their nutritional value and health-related aspects, as well as milling, baking and storing, in detail. While discussing the food habits of social classes Linné accepted as a fact that the peasants and the poor should eat less tasty bread than the rich. The less palatable bread had, however, many nutritional and health advantages. Linné paid much attention to substitutes for grain to be used in times of famine, an important topic in eighteenth century Sweden. He regarded flour made of pine bark or water arum roots as excellent famine food, was enthusiastic about the new plant, maize, but considered potato only as a poor substitute for grain. Linné and his followers praised bread not only as the core component of diet, but also for its versatile role both in health and in disease.

  12. Breads Fortified with Freeze-Dried Vegetables: Quality and Nutritional Attributes. Part 1: Breads Containing Oil as an Ingredient

    PubMed Central

    Ranawana, Viren; Raikos, Vassilios; Campbell, Fiona; Bestwick, Charles; Nicol, Phyllis; Milne, Lesley; Duthie, Garry

    2016-01-01

    There is increasing emphasis on reformulating processed foods to make them healthier. This study for the first time comprehensively investigated the effects of fortifying bread (containing oil as an ingredient) with freeze-dried vegetables on its nutritional and physico-chemical attributes. Breads fortified with carrot, tomato, beetroot or broccoli were assessed for nutrition, antioxidant potential, storage life, shelf stability, textural changes and macronutrient oxidation. Furthermore, using an in vitro model the study for the first time examined the impact of vegetable addition on the oxidative stability of macronutrients during human gastro-intestinal digestion. As expected, adding vegetables improved the nutritional and antioxidant properties of bread. Beetroot and broccoli significantly improved bread storage life. None of the vegetables significantly affected bread textural changes during storage compared to the control. Lipid oxidation in fresh bread was significantly reduced by all four types of vegetables whilst protein oxidation was lowered by beetroot, carrot and broccoli. The vegetables demonstrated varying effects on macronutrient oxidation during gastro-intestinal digestion. Beetroot consistently showed positive effects suggesting its addition to bread could be particularly beneficial. PMID:28231114

  13. Molecular monitoring of spoilage yeasts during the production of candied fruit nougats to determine food contamination sources.

    PubMed

    Martorell, Patricia; Fernández-Espinar, M Teresa; Querol, Amparo

    2005-06-15

    In the present work, we have analysed the yeast microbiota present in a manufacturing plant of candied fruits and nougats. Four yeasts species (Zygosaccharomyces bailii, Zygosaccharomyces rouxii, Sporobolomyces roseus, and Debaryomyces hansenii) and a filamentous fungi (Nectria mauriiticola) were identified according to restriction analysis of 5.8S-ITS rDNA. These identifications were subsequently confirmed by sequencing the D1/D2 domain of the 26S rRNA gene. Z. rouxii and Z. bailii were isolated at high frequency along the whole manufacturing process. Since food alteration by Z. bailii and Z. rouxii is the cause of important economic losses for the food industry, there is a need for differentiating yeasts at the strain level as an essential part of quality control programs in this industry. For this purpose, we have tested the performance of three molecular techniques (RFLP mtDNA, RAPD-PCR, and microsatellite with (GAC)5 and (GTG)5 primers) to differentiate strains belonging to these two Zygosaccharomyces species. Those techniques with the best discriminatory power were applied to differentiate Zygosaccharomyces species isolates. The results of this analysis indicate that one strain of Z. bailii and two strains of Z. rouxii were involved in the spoilage of candied fruits. Moreover, the Z. bailii strain was also present in the spoiled nougat, hence being responsible of this alteration.

  14. Antifungal activity of sourdough fermented wheat germ used as an ingredient for bread making.

    PubMed

    Rizzello, Carlo Giuseppe; Cassone, Angela; Coda, Rossana; Gobbetti, Marco

    2011-08-01

    This study aimed at investigating the antifungal activity of sourdough fermented (Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5) wheat germ (SFWG). Preliminarily, methanol and water/salt-soluble extracts from SFWG were assayed by agar diffusion towards Penicillium roqueforti DPPMAF1. As shown by hyphal radial growth rate, the water/salt-soluble extract showed the inhibition of various fungi isolated from bakeries. The antifungal activity was attributed to a mixture of organic acids and peptides which were synthesized during fermentation. Formic (24.7mM) acid showed the highest antifungal activity. Four peptides, having similarities with well known antifungal sequences, were identified and chemically synthesized. The minimal inhibitory concentration was 2.5-15.2mg/ml. Slices of bread made by addition of 4% (wt/wt) of freeze dried SFWG were packed in polyethylene bags and stored at room temperature. Slices did not show contamination by fungi until at least 28days of storage and behaved as the calcium propionate (0.3%, wt/wt).

  15. PIXE analysis of Nigerian flour and bread samples

    NASA Astrophysics Data System (ADS)

    Olise, Felix S.; Fernandes, Adriana M.; Cristina Chaves, P.; Taborda, Ana; Reis, Miguel A.

    2014-01-01

    The alleged use of potassium bromate (KBrO3) in bread baking led a few authors to report on the chemical methods for the determination of KBrO3 levels in bread. In order to examine the potentials of a non chemical particle induced X-ray emission (PIXE) method for this purpose, six sets of samples, each composed of flour, dough and bread from a production batch were analysed. The samples were obtained from six different bakers of bread at Ile-Ife, Nigeria. The flour samples were air-dried while others were freeze dried at about -16 °C. The samples were homogenised in an agate mortar and then pelletised. Samples were analysed at the CTN standard PIXE setup and standard procedures for thick target samples analysis were followed. In some samples significant concentrations of bromine were found. In the present work we present possible explanations for the presence of this potentially dangerous contaminant in the samples.

  16. Quality changes during frozen storage and thawing of mixed bread.

    PubMed

    Fik, M; Macura, R

    2001-04-01

    In the present work investigations of the dependence between frozen storage time, the method of thawing (air blast at 50 degrees C and microwave), organoleptic and physico-chemical changes in bread are reported. The quality of the thawed product was analysed directly after thawing and after two days of storage at room temperature. It was found that changes in quality of bread are more affected by frozen storage than by the employed thawing method. The thawing methods had a significant (p < or = 0.01) effect on the investigated physico-chemical parameters of the product, however, their statistically significant (p < or = 0.01) effect on the sensory quality could only be revealed after two days of storage of the previously thawed bread at room temperature rather than directly after thawing. The results obtained in the present study suggest that bread which underwent microwave thawing had generally better quality in comparison with air blast thawing.

  17. New data on the bioavailability of bread magnesium.

    PubMed

    Lopez, H W; Leenhardt, F; Remesy, C

    2004-12-01

    Whole cereal products are the main source of magnesium in human nutrition. Even if wholemeal bread is an important source of Mg, it also contains considerable amounts of phytic acid (PA), a natural chelator that lowers the absorption of trace elements such as Fe or Zn as well as Ca or Mg in cereal products. Significant Mg bioavailability improvement in bread could be supplied by the choice of raw materials and the baking processes of cereals. Improvement in the Mg content of wheat grain was proved possible by traditional plant selection. Bread making using sourdough improves the nutritional properties of bread by reducing the amounts of phytic acid and phytate breakdown, which is mainly explained by the acidity level in the sourdough process that promotes greater efficiency in the wheat phytase activity. A slight acidification due to sourdough effectively reduces the phytate content and improves Mg bioavaibility.

  18. 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

  19. Contamination of salmon fillets and processing plants with spoilage bacteria.

    PubMed

    Møretrø, Trond; Moen, Birgitte; Heir, Even; Hansen, Anlaug Å; Langsrud, Solveig

    2016-11-21

    The processing environment of salmon processing plants represents a potential major source of bacteria causing spoilage of fresh salmon. In this study, we have identified major contamination routes of important spoilage associated species within the genera Pseudomonas, Shewanella and Photobacterium in pre-rigor processing of salmon. Bacterial counts and culture-independent 16S rRNA gene analysis on salmon fillet from seven processing plants showed higher levels of Pseudomonas spp. and Shewanella spp. in industrially processed fillets compared to salmon processed under strict hygienic conditions. Higher levels of Pseudomonas spp. and Shewanella spp. were found on fillets produced early on the production day compared to later processed fillets. The levels of Photobacterium spp. were not dependent on the processing method or time of processing. In follow-up studies of two plants, bacterial isolates (n=2101) from the in-plant processing environments (sanitized equipment/machines and seawater) and from salmon collected at different sites in the production were identified by partial 16S rRNA gene sequencing. Pseudomonas spp. dominated in equipment/machines after sanitation with 72 and 91% of samples from the two plants being Pseudomonas-positive. The phylogenetic analyses, based on partial 16S rRNA gene sequencing, showed 48 unique sequence profiles of Pseudomonas of which two were dominant. Only six profiles were found on both machines and in fillets in both plants. Shewanella spp. were found on machines after sanitation in the slaughter department while Photobacterium spp. were not detected after sanitation in any parts of the plants. Shewanella spp. and Photobacterium spp. were found on salmon in the slaughter departments. Shewanella was frequently present in seawater tanks used for bleeding/short term storage. In conclusion, this study provides new knowledge on the processing environment as a source of contamination of salmon fillets with Pseudomonas spp. and

  20. Spoilage potential of Pseudomonas species isolated from goat milk.

    PubMed

    Scatamburlo, T M; Yamazi, A K; Cavicchioli, V Q; Pieri, F A; Nero, L A

    2015-02-01

    Pseudomonas spp. are usually associated with spoilage microflora of dairy products due to their proteolytic potential. This is of particular concern for protein-based products, such as goat milk cheeses and fermented milks. Therefore, the goal of the present study was to characterize the proteolytic activity of Pseudomonas spp. isolated from goat milk. Goat milk samples (n=61) were obtained directly from bulk tanks on dairy goat farms (n=12), and subjected to a modified International Organization for Standardization (ISO) protocol to determine the number and proteolytic activity of Pseudomonas spp. Isolates (n=82) were obtained, identified by PCR, and subjected to pulsed-field gel electrophoresis with XbaI macro-restriction. Then, the isolates were subjected to PCR to detect the alkaline protease gene (apr), and phenotypic tests were performed to check proteolytic activity at 7°C, 25°C, and 35°C. Mean Pseudomonas spp. counts ranged from 2.9 to 4.8 log cfu/mL, and proteolytic Pseudomonas spp. counts ranged from 1.9 to 4.6 log cfu/mL. All isolates were confirmed to be Pseudomonas spp., and 41 were identified as Pseudomonas fluorescens, which clustered into 5 groups sharing approximately 82% similarity. Thirty-six isolates (46.9%) were positive for the apr gene; and 57 (69.5%) isolates presented proteolytic activity at 7°C, 82 (100%) at 25°C, and 64 (78%) at 35°C. The isolates were distributed ubiquitously in the goat farms, and no relationship among isolates was observed when the goat farms, presence of apr, pulsotypes, and proteolytic activity were taken into account. We demonstrated proteolytic activity of Pseudomonas spp. present in goat milk by phenotypic and genotypic tests and indicated their spoilage potential at distinct temperatures. Based on these findings and the ubiquity of Pseudomonas spp. in goat farm environments, proper monitoring and control of Pseudomonas spp. during production are critical.

  1. A micromechanics model for bread dough

    NASA Astrophysics Data System (ADS)

    Mohammed, M. A. P.; Tarleton, E.; Charalambides, M. N.; Williams, J. G.

    2015-01-01

    The mechanical behaviour of dough and gluten was studied in an effort to investigate whether bread dough can be treated as a two phase (starch and gluten) composite material. The dough and gluten show rate dependent behaviour under tension, compression and shear tests, and non-linear unloading-reloading curves under cyclic compression tests. There is evidence from cryo-Scanning Electron Microscopy (SEM) that damage in the form of debonding between starch and gluten occurs when the sample is stretched. A composite finite element model was developed using starch as filler and gluten as matrix. The interaction between the starch and gluten was modelled as cohesive contact. The finite element analysis predictions agree with trends seen in experimental test data on dough and gluten, further evidence that debonding of starch and gluten is a possible damage mechanism in dough.

  2. A micromechanics model for bread dough

    SciTech Connect

    Mohammed, M. A. P; Tarleton, E.; Charalambides, M. N.; Williams, J. G.

    2015-01-22

    The mechanical behaviour of dough and gluten was studied in an effort to investigate whether bread dough can be treated as a two phase (starch and gluten) composite material. The dough and gluten show rate dependent behaviour under tension, compression and shear tests, and non-linear unloading-reloading curves under cyclic compression tests. There is evidence from cryo-Scanning Electron Microscopy (SEM) that damage in the form of debonding between starch and gluten occurs when the sample is stretched. A composite finite element model was developed using starch as filler and gluten as matrix. The interaction between the starch and gluten was modelled as cohesive contact. The finite element analysis predictions agree with trends seen in experimental test data on dough and gluten, further evidence that debonding of starch and gluten is a possible damage mechanism in dough.

  3. Fungi and mycotoxins in cocoa: from farm to chocolate.

    PubMed

    Copetti, Marina V; Iamanaka, Beatriz T; Pitt, John I; Taniwaki, Marta H

    2014-05-16

    Cocoa is an important crop, as it is the raw material from which chocolate is manufactured. It is grown mainly in West Africa although significant quantities also come from Asia and Central and South America. Primary processing is carried out on the farm, and the flavour of chocolate starts to develop at that time. Freshly harvested pods are opened, the beans, piled in heaps or wooden boxes, are fermented naturally by yeasts and bacteria, then dried in the sun on wooden platforms or sometimes on cement or on the ground, where a gradual reduction in moisture content inhibits microbial growth. Beans are then bagged and marketed. In processing plants, the dried fermented beans are roasted, shelled and ground, then two distinct processes are used, to produce powdered cocoa or chocolate. Filamentous fungi may contaminate many stages in cocoa processing, and poor practices may have a strong influence on the quality of the beans. Apart from causing spoilage, filamentous fungi may also produce aflatoxins and ochratoxin A. This review deals with the growth of fungal species and formation of mycotoxins during the various steps in cocoa processing, as well as reduction of these contaminants by good processing practices. Methodologies for fungal and mycotoxin detection and quantification are discussed while current data about dietary exposure and regulation are also presented.

  4. A salt reduction of 50% in bread does not decrease bread consumption or increase sodium intake by the choice of sandwich fillings.

    PubMed

    Bolhuis, Dieuwerke P; Temme, Elisabeth H M; Koeman, Fari T; Noort, Martijn W J; Kremer, Stefanie; Janssen, Anke M

    2011-12-01

    Bread is a major contributor to sodium intake in many countries. Reducing the salt (NaCl) content in bread might be an effective way to reduce overall sodium intake. The objectives of this study were to examine the effects of gradually lowering the salt content in brown bread, with and without flavor compensation (KCl and yeast extract), on bread consumption and sodium intake compensation by choice of sandwich fillings. A total of 116 participants (age: 21 ± 3 y; BMI: 22 ± 2 kg/m²) consumed a buffet-style breakfast on weekdays for 4 wk. Participants received either regular bread (control group: n = 39), bread whose salt content was gradually lowered each week by 0, 31, 52, and 67% (reduced group: n = 38), or bread whose salt content was also gradually lowered each week but which was also flavor compensated (compensated group: n = 39). A reduction of up to 52% of salt in bread did not lead to lower consumption of bread compared to the control (P = 0.57), whereas less bread was consumed when salt was reduced by 67% (P = 0.006). When bread was flavor compensated, however, a reduction of 67% did not lead to lower consumption (P = 0.69). Salt reduction in bread (with and without flavor compensation) did not induce sodium intake compensation (P = 0.31). In conclusion, a salt reduction of up to 52% in bread or even up to 67% in flavor-compensated bread neither affected bread consumption nor choice of sandwich fillings.

  5. Wheat-based traditional flat breads of India.

    PubMed

    Parimala, K R; Sudha, M L

    2015-01-01

    Wheat forms the basic ingredient for various bakery and traditional products. Wheat-based flat breads are one of the traditional products prepared in different parts of the world. Different regions of the world have inherited different preparation methods since time immemorial, which has led to the existence of traditional flat breads'. Being traditional, only a few have been extensively studied scientifically. India, being the second largest producer of wheat, has a great saga of traditional flat breads with different tastes and texture. This review is a compiled information related to the research studies carried out on some of the wheat-based traditional flat breads of India namely chapati, puri, tandoori roti, parantha (whole-wheat flour based) and parotta, naan, bhatura, kulcha (refined wheat flour based) which indicates the magnitude of attention they have drawn among the food scientists. The review delves upon the developments and improvements brought about in the storage stability and realization of large-scale production of few of these flat breads which has helped considerably to cater to the growing demand in the domestic as well as international markets. The review also indicates the possibility and the tremendous scope available for technological developments for traditional flat breads.

  6. Texturized pinto bean protein fortification in straight dough bread formulation.

    PubMed

    Simons, Courtney W; Hunt-Schmidt, Emily; Simsek, Senay; Hall, Clifford; Biswas, Atanu

    2014-09-01

    Pinto beans were milled and then air-classified to obtain a raw high protein fraction (RHPF) followed by extrusion to texturize the protein fraction. The texturized high protein fraction (THPF) was then milled to obtain flour, and combined with wheat flour at 5, 10, and 15% levels to make bread. The air-classification process produced flour with high concentration of lipids and phytic acid in the protein-rich fraction. However, extrusion significantly reduced hexane extractable lipid and phytic acid. However, the reduction observed may simply indicate a reduction in recovery due to bind with other components. Total protein and lysine contents in composite flours increased significantly as THPF levels increased in composite flour. Bread made with 5% THPF had 48% more lysine than the 100 % wheat flour (control). The THPF helped to maintain dough strength by reducing mixing tolerance index (MTI), maintaining dough stability and increasing departure time on Farinograph. Bread loaf volume was significantly reduced above 5% THPF addition. THPF increased water absorption causing an increase in bread weights by up to 6%. Overall, loaf quality deteriorated at 10 and 15% THPF levels while bread with 5% THPF was not significantly different from the control. These results support the addition of 5% THPF as a means to enhance lysine content of white pan bread.

  7. Speciation of chromium in bread and breakfast cereals.

    PubMed

    Mathebula, Mpho Wendy; Mandiwana, Khakhathi; Panichev, Nikolas

    2017-02-15

    Bread and breakfast cereals are a major constituents of the human diet, yet their Cr(VI) content is not known. Chromium(VI) was determined in these products by high resolution continuum source atomic absorption spectrometer (HR-CS AAS) after leaching Cr(VI) with 0.10molL(-1) Na2CO3. The results showed that 33-73% of total Cr (58.17±5.12μgkg(-1)-156.1±6.66μgkg(-1)) in bread exist as Cr(VI) and the highest total Cr content was found in brown bread. It was shown that Cr(III) is oxidized to Cr(VI) during toasting of bread. Chromium(VI) content in breakfast cereals ranged between 20.4±4μgkg(-1) and 470.4±68μgkg(-1). Therefore, it can be concluded that bread and breakfast cereals contains Cr(VI) which does not exceed maximum acceptable concentration (MAC) of 0.003mgkg(-1)bw(-1)day(-1) through daily consumption of half a bowl (65g) of breakfast cereal and four slices of toasted (122g) or untoasted bread (160g).

  8. Impact of sourdough on the texture of bread.

    PubMed

    Arendt, Elke K; Ryan, Liam A M; Dal Bello, Fabio

    2007-04-01

    Sourdough has been used since ancient times and its ability to improve the quality and increase the shelf-life of bread has been widely described. During sourdough fermentation, lactic acid bacteria (LAB) produce a number of metabolites which have been shown to have a positive effect on the texture and staling of bread, e.g. organic acids, exopolysaccharides (EPS) and/or enzymes. EPS produced by LAB have the potential to replace more expensive hydrocolloids used as bread improvers. Organic acids affect the protein and starch fractions of flour. Additionally, the drop in pH associated with acid production causes an increase in the proteases and amylases activity of the flour, thus leading to a reduction in staling. While improving the textural qualities of bread, sourdough fermentation also results in increased mineral bioavailability and reduced phytate content. In this review we will be discussing the effect of sourdough on wheat and rye bread as well as the potential of sourdough to improve the quality of gluten-free bread.

  9. Continuous biohydrogen production from waste bread by anaerobic sludge.

    PubMed

    Han, Wei; Huang, Jingang; Zhao, Hongting; Li, Yongfeng

    2016-07-01

    In this study, continuous biohydrogen production from waste bread by anaerobic sludge was performed. The waste bread was first hydrolyzed by the crude enzymes which were generated by Aspergillus awamori and Aspergillus oryzae via solid-state fermentation. It was observed that 49.78g/L glucose and 284.12mg/L free amino nitrogen could be produced with waste bread mass ratio of 15% (w/v). The waste bread hydrolysate was then used for biohydrogen production by anaerobic sludge in a continuous stirred tank reactor (CSTR). The optimal hydrogen production rate of 7.4L/(Ld) was achieved at chemical oxygen demand (COD) of 6000mg/L. According to the results obtained from this study, 1g waste bread could generate 0.332g glucose which could be further utilized to produce 109.5mL hydrogen. This is the first study which reports continuous biohydrogen production from waste bread by anaerobic sludge.

  10. Effects of ozone exposure on the xerophilic fungus, Eurotium amstelodami IS-SAB-01, isolated from naan bread.

    PubMed

    Antony-Babu, Sanjay; Singleton, Ian

    2011-01-05

    Xerophilic moulds cause contamination and spoilage of low moisture foods. This study examined the effect of ozone fumigation on growth of a Eurotium species isolated from naan bread. Two ozone treatments were used - a low-level long-term exposure (0.4 μmol/mol for 21 days) and high-level short-term exposure (300 μmol/mol for 5 to 120 min). For the low level exposure the combination of different media sucrose concentrations (0, 5, 10 and 20% w/v) with ozone treatment was also assessed. The growth of the isolate was found to be sensitive to low-level ozone fumigation depending on the media sucrose concentration and duration of the exposure. Low-level ozone exposure significantly (p<0.05) reduced the number of asexual spores formed in media with no added sucrose, an effect not observed in media with higher sucrose levels. Electron microscope observations of colonies indicated that ozone exposed cultures produced lower numbers of cleistothecia. High-level ozone exposure for short durations reduced spore viability although 100% reduction in viability was achieved only after 120 min exposure. This work demonstrates that ozone may be used to reduce spore production in Eurotium but that the ozone effect can be mediated by sucrose levels in the growth medium.

  11. Involvement of Bacterial Quorum-Sensing Signals in Spoilage of Bean Sprouts

    PubMed Central

    Rasch, Maria; Andersen, Jens Bo; Nielsen, Kristian Fog; Flodgaard, Lars Ravn; Christensen, Henrik; Givskov, Michael; Gram, Lone

    2005-01-01

    Bacterial communication signals, acylated homoserine lactones (AHLs), were extracted from samples of commercial bean sprouts undergoing soft-rot spoilage. Bean sprouts produced in the laboratory did not undergo soft-rot spoilage and did not contain AHLs or AHL-producing bacteria, although the bacterial population reached levels similar to those in the commercial sprouts, 108 to 109 CFU/g. AHL-producing bacteria (Enterobacteriaceae and pseudomonads) were isolated from commercial sprouts, and strains that were both proteolytic and pectinolytic were capable of causing soft-rot spoilage in bean sprouts. Thin-layer chromatography and liquid chromatography-high-resolution mass spectrometry revealed the presence of N-3-oxo-hexanoyl-l-homoserine lactone in spoiled bean sprouts and in extracts from pure cultures of bacteria. During normal spoilage, the pH of the sprouts increased due to proteolytic activity, and the higher pH probably facilitated the activity of pectate lyase. The AHL synthetase gene (I gene) from a spoilage Pectobacterium was cloned, sequenced, and inactivated in the parent strain. The predicted amino acid sequence showed 97% homology to HslI and CarI in Erwinia carotovora. Spoilage of laboratory bean sprouts inoculated with the AHL-negative mutant was delayed compared to sprouts inoculated with the wild type, and the AHL-negative mutant did not cause the pH to rise. Compared to the wild-type strain, the AHL-negative mutant had significantly reduced protease and pectinase activities and was negative in an iron chelation (siderophore) assay. This is the first study demonstrating AHL regulation of iron chelation in Enterobacteriaceae. The present study clearly demonstrates that the bacterial spoilage of some food products is influenced by quorum-sensing-regulated phenotypes, and understanding these processes may be useful in the development of novel food preservation additives that specifically block the quorum-sensing systems. PMID:15933035

  12. Rapid detection and identification of beer-spoilage lactic acid bacteria by microcolony method.

    PubMed

    Asano, Shizuka; Iijima, Kazumaru; Suzuki, Koji; Motoyama, Yasuo; Ogata, Tomoo; Kitagawa, Yasushi

    2009-08-01

    We evaluated a microcolony method for the detection and identification of beer-spoilage lactic acid bacteria (LAB). In this approach, bacterial cells were trapped on a polycarbonate membrane filter and cultured on ABD medium, a medium that allows highly specific detection of beer-spoilage LAB strains. After short-time incubation, viable cells forming microcolonies were stained with carboxyfluorescein diacetate (CFDA) and counted with muFinder Inspection System. In our study, we first investigated the growth behavior of various beer-spoilage LAB by traditional culture method, and Lactobacillus lindneri and several L. paracollinoides strains were selected as slow growers on ABD medium. Then the detection speeds were evaluated by microcolony method, using these slowly growing strains. As a result, all of the slowly growing beer-spoilage LAB strains were detected within 3 days of incubation. The specificity of this method was found to be exceptionally high and even discriminated intra-species differences in beer-spoilage ability of LAB strains upon detection. These results indicate that our microcolony approach allows rapid and specific detection of beer-spoilage LAB strains with inexpensive CFDA staining. For further confirmation of species status of detected strains, subsequent treatment with species-specific fluorescence in situ hybridization (FISH) probes was shown as effective for identifying the CFDA-detected microcolonies to the species level. In addition, no false-positive results arising from noise signals were recognized for CFDA staining and FISH methods. Taken together, the developed microcolony method was demonstrated as a rapid and highly specific countermeasure against beer-spoilage LAB, and compared favorably with the conventional culture methods.

  13. Adaptive Immunity to Fungi

    PubMed Central

    Verma, Akash; Wüthrich, Marcel; Deepe, George; Klein, Bruce

    2015-01-01

    Life-threatening fungal infections have risen sharply in recent years, owing to the advances and intensity of medical care that may blunt immunity in patients. This emerging crisis has created the growing need to clarify immune defense mechanisms against fungi with the ultimate goal of therapeutic intervention. We describe recent insights in understanding the mammalian immune defenses that are deployed against pathogenic fungi. We focus on adaptive immunity to the major medically important fungi and emphasize three elements that coordinate the response: (1) dendritic cells and subsets that are mobilized against fungi in various anatomical compartments; (2) fungal molecular patterns and their corresponding receptors that signal responses and shape the differentiation of T-cell subsets and B cells; and, ultimately (3) the effector and regulatory mechanisms that eliminate these invaders while constraining collateral damage to vital tissue. These insights create a foundation for the development of new, immune-based strategies for prevention or enhanced clearance of systemic fungal diseases. PMID:25377140

  14. Fun with Fungi.

    ERIC Educational Resources Information Center

    McLure, John W.

    1993-01-01

    Describes hands-on activities with fungi that may provoke the curiosity of early adolescents and increase their enjoyment and understanding of a vast, important portion of botany. Some of the activities may be conducted during the winter months when most fieldwork ceases. (PR)

  15. Aerobic sugar metabolism in the spoilage yeast Zygosaccharomyces bailii.

    PubMed

    Merico, Annamaria; Capitanio, Daniele; Vigentini, Ileana; Ranzi, Bianca Maria; Compagno, Concetta

    2003-12-01

    Despite the importance of some Zygosaccharomyces species as agents causing spoilage of food, the carbon and energy metabolism of most of them is yet largely unknown. This is the case with Zygosaccharomyces bailii. In this study the occurrence of the Crabtree effect in the petite-negative yeast Z. bailii ATCC 36947 was investigated. In this yeast the aerobic ethanol production is strictly dependent on the carbon source utilised. In glucose-limited continuous cultures a very low level of ethanol was produced. In fructose-limited continuous cultures ethanol was produced at a higher level and its production increased with the dilution rate. As a consequence, on fructose the onset of respiro-fermentative metabolism caused a reduction in biomass yield. An immediate aerobic alcoholic fermentation in Z. bailii was observed during the transition from sugar limitation to sugar excess, both on glucose and on fructose. The analysis of some key enzymes of the fermentative metabolism showed a high level of acetyl-CoA synthetase in Z. bailii growing on fructose. At high dilution rates, the activities of glucose- and fructose-phosphorylating enzymes, as well as of pyruvate decarboxylase and alcohol dehydrogenase, were higher in cells during growth on fructose than on glucose.

  16. Optimization of Pan Bread Prepared with Ramie Powder and Preservation of Optimized Pan Bread Treated by Gamma Irradiation during Storage

    PubMed Central

    Lee, Heejeong; Joo, Nami

    2012-01-01

    This study was conducted to develop an optimal composite recipe for pan bread with ramie powder that has high sensory approval with all age groups and to estimate the DPPH radical scavenging activity and the pan bread shelf life after gamma irradiation. The sensory evaluation results showed significant differences in flavor (p<0.05), appearance (p<0.01), color (p<0.01), moistness (p<0.01), and overall quality (p<0.05) based on the amount of ramie powder added. As a result, the optimum formulations by numerical and graphical methods were calculated to be as follows: ramie powder 2.76 g (0.92%) and water 184.7 mL. Optimized pan bread with ramie powder and white pan bread were irradiated with gamma-rays at doses of 0, 10, 15, and 20 kGy. The total bacterial growth increased with the longer storage time and the least amount of ramie powder added. Consequently, these results suggest that the addition of ramie powder to pan bread provides added value to the bread in terms of increased shelf life. PMID:24471063

  17. Impact of bread making on fructan chain integrity and effect of fructan enriched breads on breath hydrogen, satiety, energy intake, PYY and ghrelin.

    PubMed

    Morris, C; Lynn, A; Neveux, C; Hall, A C; Morris, G A

    2015-08-01

    Recently, there has been considerable interest in the satiety inducing properties of inulin type fructans (ITF) as a tool for weight management. As a staple food, breads provide an excellent vehicle for ITF supplementation however the integrity of the ITF chains and properties upon bread making need to be assessed. Breads enriched with 12% fructooligosaccharides (FOS) and 12% inulin were baked and the degree of polymerisation of fructans extracted from the breads were compared to those of pure compounds. An acute feeding study with a single blind cross-over design was conducted with 11 participants to investigate the effect of ITF enriched breads on breath hydrogen, self-reported satiety levels, active ghrelin, total PYY and energy intake. Size exclusion chromatography indicated that little or no depolymerisation of inulin occurred during bread making, however, there was evidence of modest FOS depolymerisation. Additionally, ITF enriched breads resulted in increased concentrations of exhaled hydrogen although statistical significance was reached only for the inulin enriched bread (p = 0.001). There were no significant differences between bread types in reported satiety (p = 0.129), plasma active ghrelin (p = 0.684), plasma PYY (p = 0.793) and energy intake (p = 0.240). These preliminary results indicate that inulin enriched bread may be a suitable staple food to increase ITF intake. Longer intervention trials are required to assess the impact of inulin enriched breads on energy intake and body weight.

  18. Sourdough microbial community dynamics: An analysis during French organic bread-making processes.

    PubMed

    Lhomme, Emilie; Urien, Charlotte; Legrand, Judith; Dousset, Xavier; Onno, Bernard; Sicard, Delphine

    2016-02-01

    Natural sourdoughs are commonly used in bread-making processes, especially for organic bread. Despite its role in bread flavor and dough rise, the stability of the sourdough microbial community during and between bread-making processes is debated. We investigated the dynamics of lactic acid bacteria (LAB) and yeast communities in traditional organic sourdoughs of five French bakeries during the bread-making process and several months apart using classical and molecular microbiology techniques. Sourdoughs were sampled at four steps of the bread-making process with repetition. The analysis of microbial density over 68 sourdough/dough samples revealed that both LAB and yeast counts changed along the bread-making process and between bread-making runs. The species composition was less variable. A total of six LAB and nine yeast species was identified from 520 and 1675 isolates, respectively. The dominant LAB species was Lactobacillus sanfranciscensis, found for all bakeries and each bread-making run. The dominant yeast species changed only once between bread-making processes but differed between bakeries. They mostly belonged to the Kazachstania clade. Overall, this study highlights the change of population density within the bread-making process and between bread-making runs and the relative stability of the sourdough species community during bread-making process.

  19. Effect of Cassava Flour Characteristics on Properties of Cassava-Wheat-Maize Composite Bread Types

    PubMed Central

    Svanberg, Ulf; Oliveira, Jorge; Ahrné, Lilia

    2013-01-01

    Replacement of wheat flour by other kinds of flour in bread making is economically important in South East Africa as wheat is mainly an imported commodity. Cassava is widely available in the region, but bread quality is impaired when large amounts of cassava are used in the bread formulation. Effect of differently processed cassavas (sun-dried, roasted and fermented) on composite cassava-wheat-maize bread quality containing cassava levels from 20 to 40% (w/w) was evaluated in combination with high-methylated pectin (HM-pectin) added at levels of 1 to 3% (w/w) according to a full factorial design. Addition of pectin to cassava flour made it possible to bake bread with acceptable bread quality even at concentration as high as 40%. In addition to cassava concentration, the type of cassava flour had the biggest effect on bread quality. With high level of cassava, bread with roasted cassava had a higher volume compared with sun-dried and fermented. The pectin level had a significant effect on improving the volume in high level roasted cassava bread. Crumb firmness similar to wheat bread could be obtained with sun-dried and roasted cassava flours. Roasted cassava bread was the only bread with crust colour similar to wheat bread. PMID:26904595

  20. Development of a food spoilage indicator for monitoring freshness of skinless chicken breast.

    PubMed

    Rukchon, Chompoonoot; Nopwinyuwong, Atchareeya; Trevanich, Sudsai; Jinkarn, Tunyarut; Suppakul, Panuwat

    2014-12-01

    A colorimetric mixed-pH dye-based indicator with potential for the development of intelligent packaging, as a "chemical barcode" for real-time monitoring of skinless chicken breast spoilage, is described. Also investigated was the relationship between the numbers of microorganisms and the amount of volatile compounds. This on-package indicator contains two groups of pH-sensitive dyes, one of which is a mixture of bromothymol blue and methyl red, while the other is a mixture of bromothymol blue, bromocresol green and phenol red. Carbon dioxide (CO2) was used as a spoilage metabolite because the degree of spoilage was related to the amount of increased CO2, and which was more than the level of total volatile basic nitrogen (TVB-N) during the storage period. Characteristics of the two groups of indicator solutions were studied, as well as their response to CO2. A kinetic approach was used to correlate the response of the indicator label to the changes in skinless chicken breast spoilage. Color changes, in terms of total color difference of a mixed-pH dye-based indicator, correlated well with CO2 levels of skinless chicken breast. Trials on skinless chicken breast samples have verified that the indicator response correlates with microbial growth patterns, thus enabling real-time monitoring of spoilage either at various constant temperatures or with temperature fluctuation.

  1. Spoilage characteristics of traditionally packaged ground beef with added lactic acid bacteria displayed at abusive temperatures.

    PubMed

    Hoyle Parks, A R; Brashears, M M; Woerner, W D; Martin, J N; Thompson, L D; Brooks, J C

    2012-02-01

    Growth of pathogenic organisms such as Escherichia coli O157:H7 and Salmonella spp. can be inhibited in ground beef through the addition of certain lactic acid-producing bacteria (LAB; Lactobacillus acidophilus NP51, Lactobacillus crispatus NP35, Pediococcus acidilactici, and Lactococcus lactis ssp. lactis). This study evaluated the effects of LAB inclusion on the organoleptic and biochemical properties typically associated with spoilage in traditionally packaged ground beef displayed at abusive (10°C) temperatures for 36 h. Trained and untrained panelist evaluations of lean color and off-odor, as well as instrumental color analyses, did not indicate an effect on spoilage traits due to LAB utilization (P > 0.05). However, display length affected each variable independently and was indicative of decreased stability and acceptability as display time (h) increased (P < 0.05). Thiobarbituric acid values were decreased for ground beef with added LAB (P < 0.05), but likely can be related to bacterial degradation of lipid oxidation by-products because no reduction in organoleptic traits due to oxidation was noted between treatments. Overall, LAB did not adversely influence the spoilage characteristics of traditionally packaged ground beef displayed at abusive temperatures for up to 36 h. Furthermore, biochemical and sensory indicators of spoilage were present for all treatments at the conclusion of display. Therefore, LAB can be added to ground beef in traditional packaging as a processing intervention without masking or delaying the expected spoilage characteristics.

  2. Efficacy of lactoferricin B in controlling ready-to-eat vegetable spoilage caused by Pseudomonas spp.

    PubMed

    Federico, Baruzzi; Pinto, Loris; Quintieri, Laura; Carito, Antonia; Calabrese, Nicola; Caputo, Leonardo

    2015-12-23

    The microbial content of plant tissues has been reported to cause the spoilage of ca. 30% of chlorine-disinfected fresh vegetables during cold storage. The aim of this work was to evaluate the efficacy of antimicrobial peptides in controlling microbial vegetable spoilage under cold storage conditions. A total of 48 bacterial isolates were collected from ready-to-eat (RTE) vegetables and identified as belonging to Acinetobacter calcoaceticus, Aeromonas media, Pseudomonas cichorii, Pseudomonas fluorescens, Pseudomonas jessenii, Pseudomonas koreensis, Pseudomonas putida, Pseudomonas simiae and Pseudomonas viridiflava species. Reddish or brownish pigmentation was found when Pseudomonas strains were inoculated in wounds on leaves of Iceberg and Trocadero lettuce and escarole chicory throughout cold storage. Bovine lactoferrin (BLF) and its hydrolysates (LFHs) produced by pepsin, papain and rennin, were assayed in vitro against four Pseudomonas spp. strains selected for their heavy spoiling ability. As the pepsin-LFH showed the strongest antimicrobial effect, subsequent experiments were carried out using the peptide lactoferricin B (LfcinB), well known to be responsible for its antimicrobial activity. LfcinB significantly reduced (P ≤ 0.05) spoilage by a mean of 36% caused by three out of four inoculated spoiler pseudomonads on RTE lettuce leaves after six days of cold storage. The reduction in the extent of spoilage was unrelated to viable cell density in the inoculated wounds. This is the first paper providing direct evidence regarding the application of an antimicrobial peptide to control microbial spoilage affecting RTE leafy vegetables during cold storage.

  3. Transformation in fungi.

    PubMed Central

    Fincham, J R

    1989-01-01

    Transformation with exogenous deoxyribonucleic acid (DNA) now appears to be possible with all fungal species, or at least all that can be grown in culture. This field of research is at present dominated by Saccharomyces cerevisiae and two filamentous members of the class Ascomycetes, Aspergillus nidulans and Neurospora crassa, with substantial contributions also from fission yeast (Schizosaccharomyces pombe) and another filamentous member of the class Ascomycetes, Podospora anserina. However, transformation has been demonstrated, and will no doubt be extensively used, in representatives of most of the main fungal classes, including Phycomycetes, Basidiomycetes (the order Agaricales and Ustilago species), and a number of the Fungi Imperfecti. The list includes a number of plant pathogens, and transformation is likely to become important in the analysis of the molecular basis of pathogenicity. Transformation may be maintained either by using an autonomously replicating plasmid as a vehicle for the transforming DNA or through integration of the DNA into the chromosomes. In S. cerevisiae and other yeasts, a variety of autonomously replicating plasmids have been used successfully, some of them designed for use as shuttle vectors for Escherichia coli as well as for yeast transformation. Suitable plasmids are not yet available for use in filamentous fungi, in which stable transformation is dependent on chromosomal integration. In Saccharomyces cerevisiae, integration of transforming DNA is virtually always by homology; in filamentous fungi, in contrast, it occurs just as frequently at nonhomologous (ectopic) chromosomal sites. The main importance of transformation in fungi at present is in connection with gene cloning and the analysis of gene function. The most advanced work is being done with S. cerevisiae, in which the virtual restriction of stable DNA integration to homologous chromosome loci enables gene disruption and gene replacement to be carried out with greater

  4. The use of potato fibre to improve bread physico-chemical properties during storage.

    PubMed

    Curti, Elena; Carini, Eleonora; Diantom, Agoura; Vittadini, Elena

    2016-03-15

    Bread staling reduction is a very important issue for the food industry. A fibre with high water holding capacity, extracted from potato peel, was studied for its ability to reduce bread staling even if employed at low level (0.4 g fibre/100 g flour). Physico-chemical properties (water activity, moisture content, frozen water content, amylopectin retrogradation) and (1)H Nuclear Magnetic Resonance molecular mobility were characterised in potato fibre added bread over 7 days of storage. Potato fibre addition in bread slightly affected water activity and moisture content, while increased frozen water content and resulted in a softer bread crumb, more importantly when the optimal amount of water was used in the formulation. Potato fibre also reduced (1)H NMR molecular mobility changes in bread crumb during storage. Potato fibre addition in bread contributed to reduce bread staling.

  5. Effect of microparticulated wheat bran on the physical properties of bread.

    PubMed

    Kim, Bum-Keun; Cho, Ah-Ra; Chun, Yong-Gi; Park, Dong-June

    2013-02-01

    Wheat bran and flour mixtures were used in a bread formulation to improve its quality characteristics. Wheat bran was microparticulated using a jet mill, and this microparticulated wheat bran (MWB) was substituted for a portion of wheat flour. As the MWB content increased, water-holding capacity, hardness and springiness increased while the swelling property decreased slightly. The hardness of bread containing MWB was lower than that made with commercial whole wheat flour (WWF). Bread containing 7% MWB had a higher specific volume (8.3%) than that of WWF bread. Enthalpy of dough decreased with increasing MWB content, and peak viscosity and breakdown decreased with increasing setback. Inner crust structures of bread containing MWB showed a slight reduction in gelatinization and gluten development in comparison with wheat bread. These results indicate that MWB could be used as a diet-enriching bread ingredient while maintaining bread quality.

  6. Molecular comparisons for identification of food spoilage yeasts and prediction of species that may develop in different food products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spoilage of foods and beverages by yeasts is often characterized by objectionable odors, appearance, taste, texture or build-up of gas in packaging containers, resulting in loss of the product. Seldom is human health compromised by products spoiled by yeasts even though some spoilage is caused by sp...

  7. Metabolism of lactic acid in fermented cucumbers by Lactobacillus buchneri and related species, potential spoilage organisms in reduced salt fermentations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent evidence suggests that Lactobacillus buchneri may play an important role in spoilage-associated secondary fermentation of cucumbers. Lactic acid degradation during fermented cucumber spoilage is influenced by sodium chloride (NaCl) concentration, pH, and presence of oxygen. Objectives were to...

  8. Reduction of spoilage of chilled vacuum-packed lamb by psychrotolerant clostridia.

    PubMed

    Adam, Katharine H; Flint, Steve H; Brightwell, Gale

    2013-02-01

    Methods for the reduction of spoilage, of lamb, by psychrotolerant clostridia were investigated including exposure to air, hot and cold water spray washing and tyndallisation. Initially vegetative cells of psychrotolerant clostridia associated with spoilage of chilled vacuum-packed meat were exposed to aerobic cooked meat medium at room temperature (21 °C) to determine how long they remained viable. Survival of strains varied from 2h to 3 days. Vegetative cells of Clostridium estertheticum subsp. estertheticum survived 7 days at 10 °C with little reduction in viable numbers. This ruled out exposure to air as a practical method for reducing spoilage. Trials were also carried out on chilled vacuum-packed lamb inoculated with spores of Cl. estertheticum subsp. estertheticum. The time until inoculated packs reached the loss of vacuum stage varied from 38 to 53 days. Hot and cold water washing extended the shelf life by 12 to 13 days in comparison to untreated packs.

  9. Isolation of a virulent Lactobacillus brevis phage and its application in the control of beer spoilage.

    PubMed

    Deasy, Therese; Mahony, Jennifer; Neve, Horst; Heller, Knut J; van Sinderen, Douwe

    2011-12-01

    Beer quality can be compromised by the growth of certain lactobacilli, in particular Lactobacillus brevis and Lactobacillus plantarum, and various strategies have been used to control such bacterial spoilage. Biocontrol by means of bacteriophage is a reemerging approach for the suppression of spoilage bacteria in food and beverage matrices. A virulent phage capable of infecting L. brevis beer-spoilage strains was isolated and morphologically assessed by electron microscopy. The myophage SA-C12 was shown to be stable in beer and capable of controlling the growth of its host, L. brevis strain 56, in commercial beer. The results of this study indicate that bacteriophage-based treatments may be used as an alternative and natural strategy for the control of bacterial contamination of beer.

  10. beta-Glucanases as a tool for the control of wine spoilage yeasts.

    PubMed

    Enrique, M; Ibáñez, A; Marcos, J F; Yuste, M; Martínez, M; Vallés, S; Manzanares, P

    2010-01-01

    In this study, the antimicrobial activity of a commercial beta-glucanase preparation against wine spoilage yeasts such as Cryptococcus albidus, Dekkera bruxellensis, Pichia membranifaciens, Saccharomyces cerevisiae, Zygosaccharomyces bailii, and Zygosaccharomyces bisporus has been evaluated. Yeast species tested showed different sensitivities to the enzyme preparation. In vitro assays in laboratory medium (GPY) showed inhibition by the beta-glucanase preparation of D. bruxellensis and Z. bailii growth with IC(50) and MIC values approximately 3 to 4-fold greater than the recommended dose for improving wine filtration. Wine spoilage experiments showed antimicrobial action against D. bruxellensis and Z. bailii although with reduced effectiveness to that showed in laboratory medium. Under the conditions tested, the addition of beta-glucanase did not affect wine enological parameters. Our data suggest the potential use of beta-glucanases as antimicrobial agents in wine and indicate that the application of antimicrobial enzymes for yeast spoilage control deserves further investigation.

  11. Lactobacilli and dairy propionibacterium with potential as biopreservatives against food fungi and yeast contamination.

    PubMed

    Ho, P H; Luo, J B; Adams, M C

    2009-01-01

    Naturally fermented and raw foods contain a range of organisms that may have benefit as additives in some foods and food processing. In particular, potential anti-fungal properties of these organisms may be potentially utilised as natural alternatives to chemical additives used to delay and prevent spoilage by fungi and yeast. This study examined 12 novel bacteria previously isolated from food as possible biopreservatives. The bacteria from the lactobacilli and dairy propionibacterium groups were tested by agar overlay method for their ability to inhibit the growth of 10 fungi and one yeast commonly associated with food contamination. Eight among eleven tested lactic acid bacteria demonstrated broad spectrum of antifungal activity. Strong fungi inhibition was also demonstrated by the dairy propionibacterium, but efficacy was growth medium dependant. Only one fungi, Geotrichum candidum was highly resistant to the bacteria. Variation between the inhibition results for different bacteria identifies the importance of careful strain selection, and the benefits of strain combinations when selecting biopreservatives for foods.

  12. Transamidation of gluten proteins during the bread-making process of wheat flour to produce breads with less immunoreactive gluten.

    PubMed

    Heredia-Sandoval, Nina Gisella; Islas-Rubio, Alma Rosa; Cabrera-Chávez, Francisco; Calderón de la Barca, Ana María

    2014-08-01

    Due to an increasing incidence of celiac disease (CD) and other gluten-related disorders, different gluten-free breads have been developed using starches and additives as a substitute for gluten. Thus, patients miss not only the taste and aroma of wheat bread but also risk their sensitive intestines. Therefore, modifying gluten to avoid an immune response in CD and its application to baking is in progress. The aim of the study was to enzymatically modify gluten on wheat flour, during bread-making avoiding the use of additives, to reduce immunoreactivity, preserving its properties. Microbial transglutaminase (mTG) or chymotrypsin (ChT) was used to bind lysine or valine to gluten proteins in a model system. The best conditions were directly applied to wheat flour for bread-making with and without punching at 45 min. Subsequently, the rheological properties of the doughs, specific volume of the loaves, immunoreactive gluten content and modification of the extracted proteins were evaluated. ChT-treated breads presented a better appearance with a more homogeneous crumb, higher specific volume values (3.34-4.25 cm(3) g(-1)) and higher reactive gluten reduction (up to 71%) than the mTG-treated ones (1.23-2.66 cm(3) g(-1)) with only a 42% reactive gluten reduction. Thus, transpeptidation during bread-making is a promising technology, although it is necessary to improve the modification process to obtain the reactive gluten reduction required in breads for the treatment of CD patients and other gluten-related disorders.

  13. Reliability and maintainability analysis of bread production line.

    PubMed

    Tsarouhas, Panagiotis H; Arvanitoyannis, Ioannis S

    2010-04-01

    The statistical analysis of the bread production line of the failure and repair data at machine and line levels was displayed. The experiment covers a period of twenty-five months. The best fit of the failure data between the common theoretical distributions was found and its parameters were computed. The reliability and hazard rate modes for all machines and the entire production line were calculated as well. The models could prove to be a useful tool to assess the current conditions, and to predict the reliability for upgrading the maintenance policy of the production line. It was pointed out that (a) the availability of the bread production line is 90.74% and went down to 86.76% because the equipment's failures cause an additional production gap in the line, (b) the 53.5% of all failures occurred at the bread machine, cooling tower machine, and volumetric-divider machine, and (c) the machines of the bread production line that displayed increasing hazard rate functions were identified. This analysis will be very useful in terms of identifying the occurring and latent problems in manufacturing process of bread and improve it.

  14. [Wheat, bread and pasta in Mediterranean diets].

    PubMed

    Pérez Rodrigo, Carmen; Ruiz Vadillo, Virginia

    2004-06-01

    Cereals in diets have varied along evolution trends in food patterns. Cereals are starchy foods and are the main source of polysacharides in the diet. In Mediterranean countries, cereals have been used in different ways, though they are mainly used as refined cereals. Wheat bread is one of the most commonly used. In the average Spanish diet, considerable changes have taken place since 1961 leading to a significant decrease in percent energy from carbohydrate. At the same time, percent energy from fat has increased as web as protein intake. These changes in the nutritional pattern reflect a continuous decrease in consumption of grains and cereals, pulses and potatoes. In the last decades, consumption of pasta however has increased as web as consumption of processed bakery products and biscuits. Scientific and epidemiological evidence show that cereals should be the main source of energy in the diet, in line with the so-called Mediterranean Diet. Polysacharides should provide 50-55% energy. In order to reach that goal, cereal, legumes and potatoes should be included in the daily diet as 4-6 portions. Whole grain cereales should be preferred or food preparations combining pasta, potatoes or rice with vegetables in order to reduce the glycemic index. Processed bakery products and biscuits should be consumed in moderation.

  15. 48 CFR 852.270-2 - Bread and bakery products-quantities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Bread and bakery products-quantities. 852.270-2 Section 852.270-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... Bread and bakery products—quantities. As prescribed in 870.111-3, insert the following clause: Bread...

  16. 48 CFR 852.270-2 - Bread and bakery products-quantities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Bread and bakery products-quantities. 852.270-2 Section 852.270-2 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS... Bread and bakery products—quantities. As prescribed in 870.111-3, insert the following clause: Bread...

  17. Factors affecting quality of batter-based gluten-free bread

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While wheat bread has been extensively studied, the quality basis for gluten-free bread remains controversial. Common gluten-free breads are prepared from soft batters, and in such systems, intact and damaged starch, pentosans, added hydrocolloids like xanthan gum and hydroxypropyl methylcellulose (...

  18. Implications of non-covalent interactions in zein-starch dough and bread quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A major limitation in the production of wheat-free breads is the lack of protein functionality in non-wheat cereals. Breads made from non-wheat flours such as rice, maize, and sorghum must be made from thick batters and are of lower quality than wheat bread. The development of visco-elastic dough f...

  19. Quality requirements of soft red winter wheat for making northern-style Chinese steamed bread

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flours of 19 soft red winter (SRW) wheat varieties having protein contents of 6.6 to 9.9% were used to determine the suitability of SRW wheat for making steamed bread and the influences of flour characteristics on the quality attributes of steamed bread. Fourteen varieties produced steamed bread of ...

  20. Inhibition of spoilage mould conidia by acetic acid and sorbic acid involves different modes of action, requiring modification of the classical weak-acid theory.

    PubMed

    Stratford, Malcolm; Plumridge, Andrew; Nebe-von-Caron, Gerhardt; Archer, David B

    2009-11-30

    Fungal spoilage of many foods is prevented by weak-acid preservatives such as sorbic acid or acetic acid. We show that sorbic and acetic acids do not both inhibit cells by lowering of internal pH alone and that the "classical weak-acid theory" must be revised. The "classical weak-acid theory" suggests that all lipophilic acids with identical pK(a) values are equally effective as preservatives, causing inhibition by diffusion of molecular acids into the cell, dissociation, and subsequent acidification of the cytoplasm. Using a number of spoilage fungi from different genera, we have shown that sorbic acid was far more toxic than acetic acid, and no correlation existed between resistance to acetic acid and resistance to sorbic acid. The molar ratio of minimum inhibitory concentrations (MICs) (acetic: sorbic) was 58 for Paecilomyces variotii and 14 for Aspergillus phoenicis. Using flow cytometry on germinating conidia of Aspergillusniger, acetic acid at pH 4.0 caused an immediate decline in the mean cytoplasmic pH (pH(i)) falling from neutrality to approximately pH 4.7 at the MIC (80 mM). Sorbic acid also caused a rapid but far smaller drop in pH(i), at the MIC (4.5 mM); the pH remained above pH 6.3. Over 0-5 mM, a number of other weak acids caused a similar fall in cytoplasmic pH. It was concluded that while acetic acid inhibition of A. niger conidia was due to cytoplasmic acidification, inhibition by sorbic acid was not. A possible membrane-mediated mode of action of sorbic acid is discussed.

  1. FRIZZY PANICLE Drives Supernumerary Spikelets in Bread Wheat1

    PubMed Central

    Dobrovolskaya, Oxana; Pont, Caroline; Sibout, Richard; Martinek, Petr; Badaeva, Ekaterina; Murat, Florent; Chosson, Audrey; Watanabe, Nobuyoshi; Prat, Elisa; Gautier, Nadine; Gautier, Véronique; Poncet, Charles; Orlov, Yuriy L.; Krasnikov, Alexander A.; Bergès, Hélène; Salina, Elena; Laikova, Lyudmila; Salse, Jerome

    2015-01-01

    Bread wheat (Triticum aestivum) inflorescences, or spikes, are characteristically unbranched and normally bear one spikelet per rachis node. Wheat mutants on which supernumerary spikelets (SSs) develop are particularly useful resources for work towards understanding the genetic mechanisms underlying wheat inflorescence architecture and, ultimately, yield components. Here, we report the characterization of genetically unrelated mutants leading to the identification of the wheat FRIZZY PANICLE (FZP) gene, encoding a member of the APETALA2/Ethylene Response Factor transcription factor family, which drives the SS trait in bread wheat. Structural and functional characterization of the three wheat FZP homoeologous genes (WFZP) revealed that coding mutations of WFZP-D cause the SS phenotype, with the most severe effect when WFZP-D lesions are combined with a frameshift mutation in WFZP-A. We provide WFZP-based resources that may be useful for genetic manipulations with the aim of improving bread wheat yield by increasing grain number. PMID:25398545

  2. Thermodynamics of bread baking: A two-state model

    NASA Astrophysics Data System (ADS)

    Zürcher, Ulrich

    2014-03-01

    Bread baking can be viewed as a complex physico-chemical process. It is governed by transport of heat and is accompanied by changes such as gelation of starch, the expansion of air cells within dough, and others. We focus on the thermodynamics of baking and investigate the heat flow through dough and find that the evaporation of excess water in dough is the rate-limiting step. We consider a simplified one-dimensional model of bread, treating the excess water content as a two-state variable that is zero for baked bread and a fixed constant for unbaked dough. We arrive at a system of coupled, nonlinear ordinary differential equations, which are solved using a standard Runge-Kutta integration method. The calculated baking times are consistent with common baking experience.

  3. Ancient hybridizations among the ancestral genomes of bread wheat.

    PubMed

    Marcussen, Thomas; Sandve, Simen R; Heier, Lise; Spannagl, Manuel; Pfeifer, Matthias; Jakobsen, Kjetill S; Wulff, Brande B H; Steuernagel, Burkhard; Mayer, Klaus F X; Olsen, Odd-Arne

    2014-07-18

    The allohexaploid bread wheat genome consists of three closely related subgenomes (A, B, and D), but a clear understanding of their phylogenetic history has been lacking. We used genome assemblies of bread wheat and five diploid relatives to analyze genome-wide samples of gene trees, as well as to estimate evolutionary relatedness and divergence times. We show that the A and B genomes diverged from a common ancestor ~7 million years ago and that these genomes gave rise to the D genome through homoploid hybrid speciation 1 to 2 million years later. Our findings imply that the present-day bread wheat genome is a product of multiple rounds of hybrid speciation (homoploid and polyploid) and lay the foundation for a new framework for understanding the wheat genome as a multilevel phylogenetic mosaic.

  4. Analytical methods for volatile compounds in wheat bread.

    PubMed

    Pico, Joana; Gómez, Manuel; Bernal, José; Bernal, José Luis

    2016-01-08

    Bread aroma is one of the main requirements for its acceptance by consumers, since it is one of the first attributes perceived. Sensory analysis, crucial to be correlated with human perception, presents limitations and needs to be complemented with instrumental analysis. Gas chromatography coupled to mass spectrometry is usually selected as the technique to determine bread volatile compounds, although proton-transfer reaction mass spectrometry begins also to be used to monitor aroma processes. Solvent extraction, supercritical fluid extraction and headspace analysis are the main options for the sample treatment. The present review focuses on the different sample treatments and instrumental alternatives reported in the literature to analyse volatile compounds in wheat bread, providing advantages and limitations. Usual parameters employed in these analytical methods are also described.

  5. Effect of the bread-making process on zearalenone levels.

    PubMed

    Heidari, Sara; Milani, Jafar; Nazari, Seyed Saman Seyed Jafar

    2014-01-01

    The effects of the bread-making process including fermentation with Saccharomyces cerevisiae and lactic acid bacteria (Lactobacillus casei, Lactobacillus rhamnosus, Lactobacillus acidophilus and Lactobacillus fermentum) and baking at 200°C on zearalenone (ZEA) levels were investigated. Standard solutions of ZEA were added to flour and then loaves of bread were prepared. Sourdough and three types of yeast including active dry yeast, instant dry yeast and compressed yeast were used for the fermentation of dough. ZEA levels in flour, dough and bread were determined by HPLC with fluorescence detection after extraction and clean-up on an immunoaffinity column. The highest reduction in levels of ZEA was found in the first fermentation (first proof), while the lowest reduction was observed in the baking stage. In addition, the results showed that compressed yeast had the maximum reduction potential on ZEA levels even at the baking stage.

  6. Plant biomass degradation by fungi.

    PubMed

    Mäkelä, Miia R; Donofrio, Nicole; de Vries, Ronald P

    2014-11-01

    Plant biomass degradation by fungi has implications for several fields of science. The enzyme systems employed by fungi for this are broadly used in various industrial sectors such as food & feed, pulp & paper, detergents, textile, wine, and more recently biofuels and biochemicals. In addition, the topic is highly relevant in the field of plant pathogenic fungi as they degrade plant biomass to either gain access to the plant or as carbon source, resulting in significant crop losses. Finally, fungi are the main degraders of plant biomass in nature and as such have an essential role in the global carbon cycle and ecology in general. In this review we provide a global view on the development of this research topic in saprobic ascomycetes and basidiomycetes and in plant pathogenic fungi and link this to the other papers of this special issue on plant biomass degradation by fungi.

  7. Recycled palm oil spoilage: Correlation between physicochemical properties and oleophilicity

    NASA Astrophysics Data System (ADS)

    Kadir, Ili Afiqa Ab; Zubairi, Saiful Irwan; Jurid, Lailatul Syema

    2016-11-01

    Palm oil is widely used for domestic and commercial frying due to its techno-economic advantages as compared to other vegetable oils. However, if the oil is used beyond its recommended usage cycle, it might lead to oil spoilage. Therefore this study focuses on the comprehensive analysis of chemical and physical properties of recycled palm oil. Recycled palm oil was prepared by frying potato strips up to 4 batches; 5 cycles for each batch) was carried out with potato (g)-to-oil (ml) ratio of 3/20 prior to physico-chemical analysis (moisture content, color measurement, viscosity, density and iodine value. From 5 tests used to indicate physico-chemical properties of recycled palm oil, only color measurement, viscosity and IV shows results accordingly to theories. Whereas moisture content and density were not comply to theories. With increasing frying times, recycled palm oil color has been darker due to chemical reaction that occurs during frying. The trend line illustrates that with increasing frying times, recycled palm oil lightness decreases. It also means that its color has been darker. Meanwhile, b* rate increase indicating that recycled palm oil show tendency towards green color. Whereas, a* rate decreased, showing low tendency towards red color. Viscosity and moisture content increase with frying cycle. This situation occurred might be due to formation of hydrolysis products which are volatile while frying process. But the remaining non-volatile compounds among the hydrolysis products might also accumulate in palm oil and thus affect the total oil/fat chemical changes. Meanwhile the density of palm oil was quite constant at 0.15 g/cm3 except for cycle 2 with 0.17 g/cm3. The result obtained from this experiment were comply with previous study that stated frying batch number is a significant variable (a = 0.05) affecting the density of oil only after 20 frying batch. The contact angle of recycled palm oil on PHBV thin film was more than 90 °. Hence it shows

  8. Spoilage evaluation, shelf-life prediction, and potential spoilage organisms of tropical brackish water shrimp (Penaeus notialis) at different storage temperatures.

    PubMed

    Dabadé, D Sylvain; den Besten, Heidy M W; Azokpota, Paulin; Nout, M J Robert; Hounhouigan, D Joseph; Zwietering, Marcel H

    2015-06-01

    Maintaining the freshness of shrimp is a concern to shrimp stakeholders. To improve shrimp quality management, it is of importance to evaluate shrimp spoilage characteristics. Therefore, microbiological, sensory, and chemical changes of naturally contaminated tropical brackish water shrimp (Penaeus notialis) during storage at 28 °C, 7 °C and 0 °C were assessed. H2S-producing bacteria were the dominant group of microorganisms at 28 °C and 7 °C whereas Pseudomonas spp. were dominant at 0 °C. Total volatile basic nitrogen and trimethylamine correlated well (R(2) > 0.90) with the sensory scores. An empirical model to predict the shelf-life of naturally contaminated tropical shrimp as a function of storage temperature was developed. Specific groups of organisms were isolated at the sensory rejection times and assessed for spoilage potential in shrimps of which the endogenous flora was heat inactivated. Isolates capable of producing strong off-odor identified by 16S rRNA sequencing were mainly lactic acid bacteria (LAB) and Enterobacteriaceae at 28 °C or 7 °C and Pseudomonas spp. and LAB at 0 °C. The study contributes to the knowledge about tropical shrimp spoilage and provides a basis for the development of methods and tools to improve shrimp quality management.

  9. Use of response surface methodology to optimise environmental stress conditions on Penicillium glabrum, a food spoilage mould.

    PubMed

    Nevarez, Laurent; Vasseur, Valérie; Debaets, Stella; Barbier, Georges

    2010-01-01

    Fungi are ubiquitous microorganisms often associated with spoilage and biodeterioration of a large variety of foods and feedstuffs. Their growth may be influenced by temporary changes in intrinsic or environmental factors such as temperature, water activity, pH, preservatives, atmosphere composition, all of which may represent potential sources of stress. Molecular-based analyses of their physiological responses to environmental conditions would help to better manage the risk of alteration and potential toxicity of food products. However, before investigating molecular stress responses, appropriate experimental stress conditions must be precisely defined. Penicillium glabrum is a filamentous fungus widely present in the environment and frequently isolated in the food processing industry as a contaminant of numerous products. Using response surface methodology, the present study evaluated the influence of two environmental factors (temperature and pH) on P. glabrum growth to determine 'optimised' environmental stress conditions. For thermal and pH shocks, a large range of conditions was applied by varying factor intensity and exposure time according to a two-factorial central composite design. Temperature and exposure duration varied from 30 to 50 °C and from 10 min to 230 min, respectively. The effects of interaction between both variables were observed on fungal growth. For pH, the duration of exposure, from 10 to 230 min, had no significant effect on fungal growth. Experiments were thus carried out on a range of pH from 0.15 to 12.50 for a single exposure time of 240 min. Based on fungal growth results, a thermal shock of 120 min at 40 °C or a pH shock of 240 min at 1.50 or 9.00 may therefore be useful to investigate stress responses to non-optimal conditions.

  10. Communication in Fungi

    PubMed Central

    Cottier, Fabien; Mühlschlegel, Fritz A.

    2012-01-01

    We will discuss fungal communication in the context of fundamental biological functions including mating, growth, morphogenesis, and the regulation of fungal virulence determinants. We will address intraspecies but also interkingdom signaling by systematically discussing the sender of the message, the molecular message, and receiver. Analyzing communication shows the close coevolution of fungi with organisms present in their environment giving insights into multispecies communication. A better understanding of the molecular mechanisms underlying microbial communication will promote our understanding of the “fungal communicome.” PMID:21961006

  11. Bread fortified with anthocyanin-rich extract from black rice as nutraceutical sources: Its quality attributes and in vitro digestibility.

    PubMed

    Sui, Xiaonan; Zhang, Yan; Zhou, Weibiao

    2016-04-01

    Anthocyanin-rich black rice extract powder (ABREP) as a nutraceutical source was fortified into bread. The quality and digestibility behaviors of bread with ABREP were evaluated through instrumental and in vitro digestion studies. The quality of bread with 2% of ABREP was not significantly (p>0.05) different from the control bread; however, increasing the ABREP level to 4% caused less elasticity and higher density of bread. A mathematical model was further developed to systemically describe the trajectory of bread digestion. The digestion rates of bread with ABREP were found to be reduced by 12.8%, 14.1%, and 20.5% for bread with 1%, 2%, and 4% of ABREP, respectively. Results of the study suggest that the fortification of anthocyanins into bread could be an alternative way to produce functional bread with a lower digestion rate and extra health benefits.

  12. Storage of parbaked bread affects shelf life of fully baked end product: a ¹H NMR study.

    PubMed

    Bosmans, Geertrui M; Lagrain, Bert; Ooms, Nand; Fierens, Ellen; Delcour, Jan A

    2014-12-15

    Full baking of earlier partially baked (parbaked) bread can supply fresh bread to the consumer at any time of the day. When parbaked bread loaves were stored at -25, 4 or 23°C, the extent of crumb to crust moisture migration and amylopectin retrogradation differed with storage temperature, and the firming rate was evidently lowest during frozen storage. The extent of crumb to crust moisture migration during parbaked bread storage largely determined the mass of the fresh finished bread, and its crumb and crust moisture contents. Initial NMR proton mobility, initial resilience, the extent of amylopectin retrogradation and changes in firmness and resilience during storage of fully baked bread were affected by its crumb moisture content. The lowest firming rate was observed for finished bread resulting from parbaked bread stored at -25°C, while the highest firming rate was observed for finished bread from parbaked bread stored at 23°C.

  13. Effects of gluten-free breads, with varying functional supplements, on the biochemical parameters and antioxidant status of rat serum.

    PubMed

    Świeca, Michał; Reguła, Julita; Suliburska, Joanna; Złotek, Urszula; Gawlik-Dziki, Urszula

    2015-09-01

    This paper examines the effects of gluten-free bread enriched with functional ingredients (milk powder, poppy, sunflower and pumpkin seeds, egg yolk, carum, hazel nuts and amaranth) on the morphological and biochemical parameters and antioxidant status of rats serum. Rats were provided test diets--gluten-free breads and water ad libitum. After 14 days, the animals were weighed and killed. A hazel nut-amaranth bread diet significantly increased the level of thrombocytes when compared to control bread. A mixed bread diet significantly decreased cholesterol levels in rats. All fortified breads decreased triglyceride levels and alanine transaminase activity and caused an increase in antiradical activity of the serum. In rats fed with poppy-milk bread, milk-seed bread and mixed bread, a marked decrease in superoxide dismutase activity was found. Enriched breads reduced the levels of triglyceride and improved the antiradical properties of serum, although the physiological relevance of this needs to be confirmed by human studies.

  14. Fusarium and other opportunistic hyaline fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter focuses on those fungi that grow in tissue in the form of hyaline or lightly colored septate hyphae. These fungi include Fusarium and other hyaline fungi. Disease caused by hyaline fungi is referred to as hyalohyphomycosis. Hyaline fungi described in this chapter include the anamorphic,...

  15. Structural changes of starch during baking and staling of rye bread.

    PubMed

    Mihhalevski, Anna; Heinmaa, Ivo; Traksmaa, Rainer; Pehk, Tõnis; Mere, Arvo; Paalme, Toomas

    2012-08-29

    Rye sourdough breads go stale more slowly than wheat breads. To understand the peculiarities of bread staling, rye sourdough bread, wheat bread, and a number of starches were studied using wide-angle X-ray diffraction, nuclear magnetic resonance ((13)C CP MAS NMR, (1)H NMR, (31)P NMR), polarized light microscopy, rheological methods, microcalorimetry, and measurement of water activity. The degree of crystallinity of starch in breads decreased with hydration and baking to 3% and increased during 11 days of storage to 21% in rye sourdough bread and to 26% in wheat bread. (13)C NMR spectra show that the chemical structures of rye and wheat amylopectin and amylose contents are very similar; differences were found in the starch phospholipid fraction characterized by (31)P NMR. The (13)C CP MAS NMR spectra demonstrate that starch in rye sourdough breads crystallize in different forms than in wheat bread. It is proposed that different proportions of water incorporation into the crystalline structure of starch during staling and changes in starch fine structure cause the different rates of staling of rye and wheat bread.

  16. Development of a novel colorimetric indicator label for monitoring freshness of intermediate-moisture dessert spoilage.

    PubMed

    Nopwinyuwong, Atchareeya; Trevanich, Sudsai; Suppakul, Panuwat

    2010-05-15

    A colorimetric mixed pH dye-based indicator with potential for the development of intelligent packaging, as a "chemical barcode" for real-time monitoring of intermediate-moisture dessert spoilage, is described. This on-package indicator contains mixed pH-sensitive dyes, bromothymol blue and methyl red, that respond through visible color change to carbon dioxide (CO(2)) as a spoilage metabolite. Both indicator solution and indicator label characteristics were studied, as well as their response to CO(2). A kinetic approach was used to correlate the response of the indicator label to the changes in intermediate-moisture dessert spoilage. Color changes, in terms of total color difference of a mixed pH dye-based indicator, correlated well with CO(2) levels of intermediate-moisture dessert. Trials on golden drop have verified that the indicator response correlates with microbial growth patterns in dessert samples, thus enabling the real-time monitoring of spoilage either at various constant temperatures or with temperature fluctuation.

  17. Characterisation of biofilms formed by Lactobacillus plantarum WCFS1 and food spoilage isolates.

    PubMed

    Fernández Ramírez, Mónica D; Smid, Eddy J; Abee, Tjakko; Nierop Groot, Masja N

    2015-08-17

    Lactobacillus plantarum has been associated with food spoilage in a wide range of products and the biofilm growth mode has been implicated as a possible source of contamination. In this study we analysed the biofilm forming capacity of L. plantarum WCFS1 and six food spoilage isolates. Biofilm formation as quantified by crystal violet staining and colony forming units was largely affected by the medium composition, growth temperature and maturation time and by strain specific features. All strains showed highest biofilm formation in Brain Heart Infusion medium supplemented with manganese and glucose. For L. plantarum biofilms the crystal violet (CV) assay, that is routinely used to quantify total biofilm formation, correlates poorly with the number of culturable cells in the biofilm. This can in part be explained by cell death and lysis resulting in CV stainable material, conceivably extracellular DNA (eDNA), contributing to the extracellular matrix. The strain to strain variation may in part be explained by differences in levels of eDNA, likely as result of differences in lysis behaviour. In line with this, biofilms of all strains tested, except for one spoilage isolate, were sensitive to DNase treatment. In addition, biofilms were highly sensitive to treatment with Proteinase K suggesting a role for proteins and/or proteinaceous material in surface colonisation. This study shows the impact of a range of environmental factors and enzyme treatments on biofilm formation capacity for selected L. plantarum isolates associated with food spoilage, and may provide clues for disinfection strategies in food industry.

  18. Inactivation of spoilage bacteria in package by dielectric barrier discharge atmospheric cold plasma - treatment time effects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective was to investigate the effect of treatment time of dielectric barrier discharge atmospheric cold plasma (DBD-ACP) on inactivation of spoilage bacteria, Pseudomonas fluorescens and Macrococcus caseolyticus. P. fluorescens and M. caseolyticus were isolated from spoiled chicken carcasses ...

  19. Photocatalytic disinfection of spoilage bacteria Pseudomonas fluorescens and Macrococcus caseolyticus by nano-TiO2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Photocatalytic disinfection of spoilage bacteria gram-negative (G-) P. fluorescens and gram-positive (G+) M. caseolyticus by nano-TiO2 under different experimental conditions and the disinfection mechanism were investigated. The experimental conditions included the initial bacterial populations, nan...

  20. Spoilage of sous vide cooked salmon (Salmo salar) stored under refrigeration.

    PubMed

    Díaz, P; Garrido, M D; Bañón, S

    2011-02-01

    The spoilage of Sous Vide 'SV' cooked salmon stored under refrigeration was studied. Samples were packaged under vacuum in polyamide-polypropylene pouches, cooked at an oven temperature/time of 80 (°)C/45 min, quickly chilled at 3 (°)C and stored at 2 (°)C for 0, 5 or 10 weeks for catering use. Microbial (aerobic and anaerobic psychrotrophs, lactic acid bacteria, molds and yeasts and Enterobacteriaceae), physical-chemical (pH, water activity, TBARS, acidity, L*a*b* color, texture profile analysis and shear force) and sensory (appearance, odor, flavor, texture and overall quality) parameters were determined. SV processing prevented the growth of aerobic and anaerobic psychrotrophs, lactic acid bacteria, molds and yeasts and Enterobacteriaceae. There were no relevant changes in pH, water activity, TBARS, CIELab color associated with cooked salmon spoilage. Instrumental texture data were contradictory. Slight decrease in lactic acid levels was found. In contrast, the SV cooked salmon suffered considerable sensory deterioration during its refrigerated storage, consisting of severe losses of cooked salmon odor and flavor, slight rancidity, discoloration associated with white precipitation, and moderates softness, and loss of chewiness and juiciness. No acidification, putrefaction or relevant rancidity was detected. The sensory spoilage preceded microbiological and physical-chemical spoilage, suggesting that microbiological quality alone may overestimate the shelf life of SV cooked salmon.

  1. Characterization of cucumber fermentation spoilage bacteria by enrichment culture and 16S rDNA cloning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Commercial cucumber fermentations are typically carried out in 40000 L fermentation tanks. A secondary fermentation can occur after sugars are consumed that results in the formation of acetic, propionic, and butyric acids, concomitantly with the loss of lactic acid and an increase in pH. Spoilage fe...

  2. Effect of fermentation on naturally occurring deoxynivalenol (DON) in Argentinean bread processing technology.

    PubMed

    Samar, M M; Neira, M S; Resnik, S L; Pacin, A

    2001-11-01

    The stability of naturally occurring DON was evaluated during the fermentation stage of the bread-making process on a pilot scale. Two different products, French bread and Vienna bread, were prepared with naturally contaminated wheat flour (150 mg kg(-1)) under controlled experimental conditions. Dough was fermented at 30, 40 and 50 degrees C according to standard procedures employed in Argentinean low-technology bakeries. When the dough was fermented at 50 degrees C, the maximum reduction was 56% for the Vienna bread, with French bread being reduced by 41%. DON reduction during bread-making occurs not only in the baker due to thermal decomposition, but also during the fermentation step. The Argentinean traditional bread-making process might reduce DON levels during the fermentation stages if the dough is leavened at temperatures > 30 degrees C.

  3. Murdered bread, living bread: Doris Grant and the homemade, wholemeal loaf.

    PubMed

    Whipple, Amy C

    2011-06-01

    Doris Grant (1905-2003), a middle-class, British housewife, published numerous books from the 1940s into the 1970s urging her fellow housewives to bake organic, wholemeal bread for their families. This article argues that Grant's arguments defy easy categorization as either 'conservative' or 'progressive'. On the one hand, her targeted appeal to women reflected a traditional, conservative understanding of gender roles: women were, first and foremost, wives and mothers and therefore naturally responsible for family diet and health. On the other hand, Grant also pushed her readers to look beyond their homes and recognize a dangerous food supply system that was impinging on their daily lives. She demanded that her readers reject comfortable complicity in this system and preached the value of individual action in effecting substantive change.

  4. Spoilage and safety characteristics of ground beef treated with lactic acid bacteria.

    PubMed

    Hoyle, A R; Brooks, J C; Thompson, L D; Palmore, W; Stephens, T P; Brashears, M M

    2009-11-01

    Lactic acid bacteria (LAB) can decrease numbers of Escherichia coli O157:H7 and Salmonella in ground beef during storage. Two dose-titration studies were conducted in ground beef to determine dose levels of LAB needed to inhibit the pathogens. A second study evaluated whether LAB masked changes typically associated with the spoilage of ground beef displayed under refrigerated (0 degrees C) or abusive (10 degrees C) temperatures packaged in both traditional overwrap (TOP) and modified atmosphere packaging (MAP; 80% O(2)-20% CO(2)). Microbial analyses were conducted to determine spoilage endpoints and pathogen reduction. In the dose-titration study, Salmonella was reduced by 3 log cycles at all doses (10(6), 10(7), and 10(8) LAB per g) after 3 days of storage and was eliminated after 5 days of storage. E. coli O157:H7 was reduced by 2 log cycles at all dosages after 3 days of storage and by 3 log cycles after 5 days of storage. In the spoilage studies, as expected, total aerobic plate counts and LAB populations in LAB-inoculated samples were higher than the controls initially, but the counts were similar near the end of the study. While total spoilage bacteria generally increased over time, very few differences existed between treatments stored at 0 degrees C and 10 degrees C in coliforms, Brochothrix thermosphacta, yeasts and molds, and Pseudomonas spp. counts for both the TOP and MAP samples. We conclude that LAB could potentially be added to ground beef in TOP and MAP as a processing intervention for E. coli O157:H7 and Salmonella without masking microbial spoilage characteristics.

  5. Changes in the spoilage-related microbiota of beef during refrigerated storage under different packaging conditions.

    PubMed

    Ercolini, Danilo; Russo, Federica; Torrieri, Elena; Masi, Paolo; Villani, Francesco

    2006-07-01

    The microbial spoilage of beef was monitored during storage at 5 degrees C under three different conditions of modified-atmosphere packaging (MAP): (i) air (MAP1), (ii) 60% O2 and 40% CO2 (MAP2), and (iii) 20% O2 and 40% CO2 (MAP3). Pseudomonas, Enterobacteriaceae, Brochothrix thermosphacta, and lactic acid bacteria were monitored by viable counts and PCR-denaturing gradient gel electrophoresis (DGGE) analysis during 14 days of storage. Moreover, headspace gas composition, weight loss, and beef color change were also determined at each sampling time. Overall, MAP2 was shown to have the best protective effect, keeping the microbial loads and color change to acceptable levels in the first 7 days of refrigerated storage. The microbial colonies from the plate counts of each microbial group were identified by PCR-DGGE of the variable V6-V8 region of the 16S rRNA gene. Thirteen different genera and at least 17 different species were identified after sequencing of DGGE fragments that showed a wide diversity of spoilage-related bacteria taking turns during beef storage in the function of the packaging conditions. The countable species for each spoilage-related microbial group were different according to packaging conditions and times of storage. In fact, the DGGE profiles displayed significant changes during time and depending on the initial atmosphere used. The spoilage occurred between 7 and 14 days of storage, and the microbial species found in the spoiled meat varied according to the packaging conditions. Rahnella aquatilis, Rahnella spp., Pseudomonas spp., and Carnobacterium divergens were identified as acting during beef storage in air (MAP1). Pseudomonas spp. and Lactobacillus sakei were found in beef stored under MAP conditions with high oxygen content (MAP2), while Rahnella spp. and L. sakei were the main species found during storage using MAP3. The identification of the spoilage-related microbiota by molecular methods can help in the effective establishment of

  6. Analysis of Growth Inhibition and Metabolism of Hydroxycinnamic Acids by Brewing and Spoilage Strains of Brettanomyces Yeast.

    PubMed

    Lentz, Michael; Harris, Chad

    2015-10-15

    Brettanomyces yeasts are well-known as spoilage organisms in both the wine and beer industries, but also contribute important desirable characters to certain beer styles. These properties are mediated in large part by Brettanomyces' metabolism of hydroxycinnamic acids (HCAs) present in beverage raw materials. Here we compare growth inhibition by, and metabolism of, HCAs among commercial brewing strains and spoilage strains of B. bruxellensis and B. anomalus. These properties vary widely among the different strains tested and between the HCAs analyzed. Brewing strains showed more efficient metabolism of ferulic acid over p-coumaric acid, a trait not shared among the spoilage strains.

  7. Analysis of Growth Inhibition and Metabolism of Hydroxycinnamic Acids by Brewing and Spoilage Strains of Brettanomyces Yeast

    PubMed Central

    Lentz, Michael; Harris, Chad

    2015-01-01

    Brettanomyces yeasts are well-known as spoilage organisms in both the wine and beer industries, but also contribute important desirable characters to certain beer styles. These properties are mediated in large part by Brettanomyces’ metabolism of hydroxycinnamic acids (HCAs) present in beverage raw materials. Here we compare growth inhibition by, and metabolism of, HCAs among commercial brewing strains and spoilage strains of B. bruxellensis and B. anomalus. These properties vary widely among the different strains tested and between the HCAs analyzed. Brewing strains showed more efficient metabolism of ferulic acid over p-coumaric acid, a trait not shared among the spoilage strains. PMID:28231223

  8. Metabolomics protocols for filamentous fungi.

    PubMed

    Gummer, Joel P A; Krill, Christian; Du Fall, Lauren; Waters, Ormonde D C; Trengove, Robert D; Oliver, Richard P; Solomon, Peter S

    2012-01-01

    Proteomics and transcriptomics are established functional genomics tools commonly used to study filamentous fungi. Metabolomics has recently emerged as another option to complement existing techniques and provide detailed information on metabolic regulation and secondary metabolism. Here, we describe broad generic protocols that can be used to undertake metabolomics studies in filamentous fungi.

  9. 21 CFR 161.175 - Frozen raw breaded shrimp.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... optional forms of shrimp are: (1) Fantail or butterfly: Prepared by splitting the shrimp; the shrimp are... may be left attached. (2) Butterfly, tail off: Prepared by splitting the shrimp; tail fins and all...) “Breaded fantail shrimp.” The word “butterfly” may be used in lieu of “fantail” in the name. (2)...

  10. 21 CFR 161.175 - Frozen raw breaded shrimp.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... optional forms of shrimp are: (1) Fantail or butterfly: Prepared by splitting the shrimp; the shrimp are... may be left attached. (2) Butterfly, tail off: Prepared by splitting the shrimp; tail fins and all...) “Breaded fantail shrimp.” The word “butterfly” may be used in lieu of “fantail” in the name. (2)...

  11. 21 CFR 161.175 - Frozen raw breaded shrimp.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... optional forms of shrimp are: (1) Fantail or butterfly: Prepared by splitting the shrimp; the shrimp are... may be left attached. (2) Butterfly, tail off: Prepared by splitting the shrimp; tail fins and all...) “Breaded fantail shrimp.” The word “butterfly” may be used in lieu of “fantail” in the name. (2)...

  12. 21 CFR 161.175 - Frozen raw breaded shrimp.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... optional forms of shrimp are: (1) Fantail or butterfly: Prepared by splitting the shrimp; the shrimp are... may be left attached. (2) Butterfly, tail off: Prepared by splitting the shrimp; tail fins and all...) “Breaded fantail shrimp.” The word “butterfly” may be used in lieu of “fantail” in the name. (2)...

  13. 21 CFR 161.175 - Frozen raw breaded shrimp.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... optional forms of shrimp are: (1) Fantail or butterfly: Prepared by splitting the shrimp; the shrimp are... may be left attached. (2) Butterfly, tail off: Prepared by splitting the shrimp; tail fins and all...) “Breaded fantail shrimp.” The word “butterfly” may be used in lieu of “fantail” in the name. (2)...

  14. Up-Close Look at 'Bread-Basket'

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA's Mars Exploration Rover Spirit took this image with its front hazard-avoidance camera on sol 175 (June 30, 2004). It captures the instrument deployment device in perfect position as the rover uses its microscopic imager to get an up-close look at the rock target 'Bread-Basket.'

  15. Modelling thermal degradation of zearalenone in maize bread during baking.

    PubMed

    Numanoglu, E; Yener, S; Gökmen, V; Uygun, U; Koksel, H

    2013-01-01

    The thermal degradation of zearalenone (ZEA) was investigated using a crust-like model, representing maize bread, which was prepared with naturally contaminated maize flour. Model samples were heated under isothermal conditions at the temperature range of 100-250°C. No reduction was observed at 100°C. Thermal degradation rate constants (k) were calculated as 0.0017, 0.0143 and 0.0216 min(-1) for 150, 200 and 250°C, respectively. Maize bread baked at 250°C for 70 min was used to test the capability of model kinetic data for the prediction of ZEA reduction. The time-temperature history in the crust and crumb parts was recorded separately. Partial degradation of ZEA at each time interval was calculated by means of the corresponding k-values obtained by using the Arrhenius equation, and the total reduction occurring at the end of the entire baking process was predicted. The reduction in the crumb and crust of bread was also experimentally determined and found to be consistent with the predicted values. It was concluded that the kinetic constants determined by means of the crust-like model could be used to predict the ZEA reduction occurring during baking of maize bread.

  16. Marketing whole grain breads in Canada via food labels.

    PubMed

    Sumanac, Dunja; Mendelson, Rena; Tarasuk, Valerie

    2013-03-01

    A recommendation for increased whole grain consumption was released in Canada in 2007 to promote adequate intakes of fibre and magnesium. Since then, a proliferation of 'whole grain' claims on food packaging has been observed, but whole grain labelling is voluntary and unregulated in Canada. Through a detailed survey of bread sold in three supermarkets, this study examined how the presence of front-of-package reference to whole grain relates to (i) the presence and nature of whole grain ingredients, (ii) nutrient content, and (iii) price of the product. Twenty-one percent of breads bore a reference to whole grain on the front-of-package and the front-of-package reference to whole grain was a better predictor of fibre content than any information that could be gleaned from the ingredient list. On average, breads with a whole grain reference were higher in fibre and magnesium and lower in sodium. Mean price did not differ by presence of a whole grain reference, but breads with whole grain labelling were less likely to be low in price. Voluntary nutrition labelling may be targeting a discrete market of health-conscious consumers who are willing to pay premium prices for more healthful options.

  17. Freezing effect on bread appearance evaluated by digital imaging

    NASA Astrophysics Data System (ADS)

    Zayas, Inna Y.

    1999-01-01

    In marketing channels, bread is sometimes delivered in a frozen sate for distribution. Changes occur in physical dimensions, crumb grain and appearance of slices. Ten loaves, twelve bread slices per loaf were scanned for digital image analysis and then frozen in a commercial refrigerator. The bread slices were stored for four weeks scanned again, permitted to thaw and scanned a third time. Image features were extracted, to determine shape, size and image texture of the slices. Different thresholds of grey levels were set to detect changes that occurred in crumb, images were binarized at these settings. The number of pixels falling into these gray level settings were determined for each slice. Image texture features of subimages of each slice were calculated to quantify slice crumb grain. The image features of the slice size showed shrinking of bread slices, as a results of freezing and storage, although shape of slices did not change markedly. Visible crumb texture changes occurred and these changes were depicted by changes in image texture features. Image texture features showed that slice crumb changed differently at the center of a slice compared to a peripheral area close to the crust. Image texture and slice features were sufficient for discrimination of slices before and after freezing and after thawing.

  18. The Earth's Crust: A Lesson with Breads and Spreads.

    ERIC Educational Resources Information Center

    Swartz, Maurice L.

    1980-01-01

    Presented are activities for students in grades 3-6 which use assorted breads and spreads to represent layers of the earth's crust. It is suggested that in addition to providing good nutrition, this method has helped the children use the processes of science to deduce some basic principles of geology. (KC)

  19. Bread in a Bag. Teacher's Packet. Revised Edition.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Education, Oklahoma City.

    This unit is designed to familiarize students in grades 3-6 with wheat production; teach them the nutritional value of wheat products and their role in a well-balanced diet; and give then an easy, hands-on experience in bread making with a nominal amount of cleanup for teachers. The kit suggests that in the first week, teachers discuss wheat…

  20. Texturized pinto bean protein fortification in straight dough bread formulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pinto beans were milled and then air-classified to obtain a raw high protein fraction (RHPF) followed by extrusion to texturize the protein fraction. The texturized high protein fraction (THPF) was then milled to obtain flour, and combined with wheat flour at 5%, 10%, and 15% levels to make bread. A...

  1. Lectins in human pathogenic fungi.

    PubMed

    Gallegos, Belém; Martínez, Ruth; Pérez, Laura; Del Socorro Pina, María; Perez, Eduardo; Hernández, Pedro

    2014-01-01

    Lectins are carbohydrate-binding proteins widely distributed in nature. They constitute a highly diverse group of proteins consisting of many different protein families that are, in general, structurally unrelated. In the last few years, mushroom and other fungal lectins have attracted wide attention due to their antitumour, antiproliferative and immunomodulatory activities. The present mini-review provides concise information about recent developments in understanding lectins from human pathogenic fungi. A bibliographic search was performed in the Science Direct and PubMed databases, using the following keywords "lectin", "fungi", "human" and "pathogenic". Lectins present in fungi have been classified; however, the role played by lectins derived from human pathogenic fungi in infectious processes remains uncertain; thus, this is a scientific field requiring more research. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).

  2. 'Bread Loaf' Mesa East of Phlegra Montes

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    An isolated mesa east of the Phlegra Montes in northeastern Elysium Planitia has a cracked surface that, combined with its overall shape, gives the appearance of a giant loaf of bread. Other mesas with similar surfaces are found in the area, suggesting that at one time these mesas were part of a continuous layer of material. It is likely that at that time, some process caused the graben-like cracks to form. Later erosion of the cracked layer left only the isolated mesas seen in the THEMIS image. One clue that supports this scenario is the presence of many filled and eroded craters throughout the scene but no fresh ones. One way to produce this landscape begins with an ancient and heavily cratered surface that subsequently is buried by some other material. If this overburden was stripped off relatively recently, not enough time would have passed to allow for a new population of fresh craters to be produced. The result would be a landscape with isolated mesas of younger material on top of an ancient, cratered surface.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor

  3. Molecular characterization of ochratoxigenic fungi associated with raisins.

    PubMed

    Gashgari, Rukaia M; Shebany, Yassmin M; Gherbawy, Youssuf A

    2011-11-01

    Dried grapes (raisin) may carry a significant mycological load contaminated via cultivation, postharvest processing practices, and drying processing. The contamination of raisin with fungi can accelerate spoilage or illness, if pathogens are present. Since raisins are used as food additives in many dishes in Saudi kitchen, there are healthy concerns on the safety of raisins consumed. In this article, the mycological profile of raisins sold in different markets at Jeddah, Kingdom of Saudi Arabia, was studied. The black raisin samples showed high fungal load compared with the white samples. Aspergillus, Alternaria, Cladosporium, Epicoccum Fusarium, and Rhizopus were the most prevalent genera isolated from raisin samples. Among six Aspergillus species isolated in this study, As. carbonarius and As. niger were the most frequently isolated species. Ochratoxin A (OTA) production in raisins was investigated using a combination of chromatographical (thin layer) and molecular (random amplified polymorphic DNA and Multiplex polymerase chain reaction) techniques. The OTA was detected in 70% of the raisin samples. Also, As. carbonarius (14 out of 19 isolates) and As. niger (2 isolates out of 9) were recognized as potential producers for OTA. Also, some molecular markers for detecting the contamination of raisin samples with OTA directly without isolating the producers were tested.

  4. New cinnamon-based active paper packaging against Rhizopusstolonifer food spoilage.

    PubMed

    Rodríguez, A; Nerín, C; Batlle, R

    2008-08-13

    A new active paper package based on the incorporation of cinnamon essential oil to solid wax paraffin as an active coating is proposed, developed, and evaluated. The antifungal activity of the active paper is tested against Rhizopusstolonifer, and the results demonstrate that 6% (w/w) of the essential oil in the active coating formulation completely inhibits the growth of R. stolonifer, whereas 4% still has strong antimicrobial activity in in vitro conditions. Then, active paper is evaluated with actual food, sliced bread, using different storage times. After 3 days of storage, almost complete inhibition is obtained with 6% cinnamon essential oil. Qualitative analysis by solid-phase microextraction and determination of cinnamaldehyde in the sliced bread were also performed and confirmed the strong correspondence between the inhibition of the mold and the amount of cinnamaldehyde in the bread.

  5. A study on fibre addition to gluten free bread: its effects on bread quality and in vitro digestibility.

    PubMed

    Sciarini, L S; Bustos, M C; Vignola, M B; Paesani, C; Salinas, C N; Pérez, G T

    2017-01-01

    The aim of this study was to assess the impact of fibre addition on gluten-free (GF) dough properties and bread technological quality, and on protein and starch in vitro digestibility. Soluble (Inulin, In) and insoluble fibres (oat fibre, OF, and type IV resistant starch, RSIV) were used at 5 and 10% substitution levels. Dough firmness increased when insoluble fibres were added, and decreased when In was used. Incorporation of insoluble fibres resulted into bread with a low specific volume (SBV) since firmer dough were more difficult to expand during proofing and baking. Staling rate was reduced after fibre addition, with the exception being OF 10%, as its lower SBV may have favoured molecule re-association. In general, protein and starch digestibility increased when fibres were added at 5%, and then decreased after further increasing the level. Fibres may have disrupted bread crumb structure, thus increasing digestibility, although the higher addition may have led to a physical and/or chemical impediment to digestion. Inulin has well-known physiological effects, while RS presented the most important effect on in vitro starch digestibility (GI). These results showed the possibility of adding different fibres to GF bread to decrease the GI and increase protein digestibility, while obtaining an overall high quality end-product.

  6. Breads enriched with guava flour as a tool for studying the incorporation of phenolic compounds in bread melanoidins.

    PubMed

    Alves, Genilton; Perrone, Daniel

    2015-10-15

    In the present study we aimed at studying, for the first time, the incorporation of phenolic compounds into bread melanoidins. Fermentation significantly affected the phenolics profile of bread doughs. Melanoidins contents continuously increased from 24.1 mg/g to 71.9 mg/g during baking, but their molecular weight decreased at the beginning of the process and increased thereafter. Enrichment of white wheat bread with guava flour increased the incorporation of phenolic compounds up to 2.4-fold. Most phenolic compounds showed higher incorporation than release rates during baking, leading to increases from 3.3- to 13.3-fold in total melanoidin-bound phenolics. Incorporation patterns suggested that phenolic hydroxyls, but not glycosidic bonds of melanoidin-bound phenolics are cleaved during thermal processing. Antioxidant capacity of bread melanoidins increased due to enrichment with guava flour and increasing baking periods and was partially attributed to bound phenolics. Moreover, FRAP assay was more sensitive to measure this parameter than TEAC assay.

  7. Modification of Appetite by Bread Consumption: A Systematic Review of Randomized Controlled Trials.

    PubMed

    Gonzalez-Anton, Carolina; Artacho, Reyes; Ruiz-Lopez, Maria D; Gil, Angel; Mesa, Maria D

    2015-10-19

    The inclusion of different ingredients or the use of different baking technologies may modify the satiety response to bread, and aid in the control of food intake. The aim of this study was to perform a systematic search of randomized clinical trials on the effect of bread consumption on appetite ratings in humans. The search equation was ("Bread"[MeSH]) AND ("Satiation"[MeSH] OR "Satiety response"[MeSH]), and the filter 'clinical trials'. As a result of this procedure, 37 publications were selected. The satiety response was considered as the primary outcome. The studies were classified as follows: breads differing in their flour composition, breads differing in ingredients other than flours, breads with added organic acids or breads made using different baking technologies. Additionally, we have revised the data related to the influence of bread on glycemic index, insulinemic index and postprandial gastrointestinal hormones responses. The inclusion of appropriate ingredients such as fiber, proteins, legumes, seaweeds and acids into breads and the use of specific technologies may result in the development of healthier breads that increase satiety and satiation, which may aid in the control of weight gain and benefit postprandial glycemia. However, more well-designed randomized control trials are required to reach final conclusions.

  8. Wheat Bread with Pumpkin (Cucurbita maxima L.) Pulp
as a Functional Food Product

    PubMed Central

    Gawlik-Dziki, Urszula; Dziki, Dariusz; Jakubczyk, Anna; Karaś, Monika; Różyło, Krzysztof

    2014-01-01

    Summary In this study, a new application of pumpkin pulp in bread production is shown. The aim of this work is to determine the influence of the addition of fresh pumpkin pulp directly into wheat flour on physical, sensorial and biological properties of bread. The bioaccessibility of active compounds was also studied. An increase in the addition of pumpkin pulp from 5 to 20% (converted to dry matter) caused a decrease of bread volume and increase of crumb hardness and cohesiveness. The sensory characteristics of the bread showed that a partial replacement of wheat flour with up to 10% of pumpkin pulp gave satisfactory results. The taste, aroma and overall acceptability of control bread and bread containing 5 or 10% of pulp had the highest degree of liking. The addition of higher levels of pumpkin pulp caused an unpleasant aroma and taste. Pumpkin pulp is a good material to complement the bread with potentially bioaccessible phenolics (including flavonoids) and, especially, with peptides. The highest antioxidant activity was observed, in most cases, of the samples with added 10 and 15% of pumpkin pulp. The addition of the pulp significantly enriched the bread with potentially bioaccessible angiotensin-converting enzyme (ACE) inhibitors. The highest activity was determined in the bread with 15 and 20% pumpkin pulp. ACE inhibitors from the tested bread were highly bioaccessible in vitro. Pumpkin pulp seems to be a valuable source of active compounds to complement the wheat bread. Adding the pulp directly to the wheat flour gives satisfactory baking results and reduces the cost of production. Additionally, pumpkin pulp is sometimes treated as waste material after the acquisition of seeds, thus using it as bread supplement also has environmental and economic benefits. Key words: pumpkin, bread, texture, antioxidants, bioaccessibility in vitro, angiotensin-converting enzyme (ACE) inhibition PMID:27904316

  9. Wheat Bread with Pumpkin (Cucurbita maxima L.) Pulp
as a Functional Food Product.

    PubMed

    Różyło, Renata; Gawlik-Dziki, Urszula; Dziki, Dariusz; Jakubczyk, Anna; Karaś, Monika; Różyło, Krzysztof

    2014-12-01

    In this study, a new application of pumpkin pulp in bread production is shown. The aim of this work is to determine the influence of the addition of fresh pumpkin pulp directly into wheat flour on physical, sensorial and biological properties of bread. The bioaccessibility of active compounds was also studied. An increase in the addition of pumpkin pulp from 5 to 20% (converted to dry matter) caused a decrease of bread volume and increase of crumb hardness and cohesiveness. The sensory characteristics of the bread showed that a partial replacement of wheat flour with up to 10% of pumpkin pulp gave satisfactory results. The taste, aroma and overall acceptability of control bread and bread containing 5 or 10% of pulp had the highest degree of liking. The addition of higher levels of pumpkin pulp caused an unpleasant aroma and taste. Pumpkin pulp is a good material to complement the bread with potentially bioaccessible phenolics (including flavonoids) and, especially, with peptides. The highest antioxidant activity was observed, in most cases, of the samples with added 10 and 15% of pumpkin pulp. The addition of the pulp significantly enriched the bread with potentially bioaccessible angiotensin-converting enzyme (ACE) inhibitors. The highest activity was determined in the bread with 15 and 20% pumpkin pulp. ACE inhibitors from the tested bread were highly bioaccessible in vitro. Pumpkin pulp seems to be a valuable source of active compounds to complement the wheat bread. Adding the pulp directly to the wheat flour gives satisfactory baking results and reduces the cost of production. Additionally, pumpkin pulp is sometimes treated as waste material after the acquisition of seeds, thus using it as bread supplement also has environmental and economic benefits. Key words: pumpkin, bread, texture, antioxidants, bioaccessibility in vitro, angiotensin-converting enzyme (ACE) inhibition.

  10. Isolation and identification of spoilage microorganisms using food-based media combined with rDNA sequencing: ranch dressing as a model food.

    PubMed

    Waite, Joy G; Jones, Joseph M; Yousef, Ahmed E

    2009-05-01

    Investigating microbial spoilage of food is hampered by the lack of suitable growth media and protocols to characterize the causative agents. Microbial spoilage of salad dressing is sporadic and relatively unpredictable, thus processors struggle to develop strategies to minimize or prevent spoilage of this product. The objectives of this study were to (i) induce and characterize spoilage events in ranch-style dressing as a model food, and (ii) isolate and identify the causative microorganisms using traditional and food-based media, coupled with rDNA sequence analysis. Ranch dressing (pH 4.4) was prepared and stored at 25 degrees C for 14 d and microbial populations were recovered on MRS agar and ranch dressing agar (RDA), a newly formulated food-based medium. When isolates suspected as the spoilage agents were inoculated into ranch dressing and held at 25 degrees C for 9-10 d, three unique spoilage events were characterized. Using rDNA sequence comparisons, spoilage organisms were identified as Lactobacillus brevis, Pediococcus acidilactici, and Torulaspora delbrueckii. P. acidilactici produced flat-sour spoilage, whereas Lb. brevis resulted in product acidification and moderate gas production. The RDA medium allowed for optimum recovery of the excessive gas-producing spoilage yeast, T. delbrueckii. The isolation and identification strategy utilized in this work should assist in the characterization of spoilage organisms in other food systems.

  11. Quorum sensing signals affect spoilage of refrigerated large yellow croaker (Pseudosciaena crocea) by Shewanella baltica.

    PubMed

    Zhu, Junli; Zhao, Aifei; Feng, Lifang; Gao, Haichun

    2016-01-18

    In this work we investigated the specific spoilage organism (SSO) of large yellow croaker (Pseudosciaena crocea) stored at 4°C and role of quorum sensing (QS) system of SSO isolated from the spoiled fish. According to microbial count and 16S rRNA gene of the isolated pure strains, Shewanella, mainly Shewanella baltica and Shewanella putrefaciens, was predominant genera at the end of shelf-life of P. crocea. Among Shewanella isolates, S.baltica02 was demonstrated as SSO in spoilage potential characteristics by inoculation into sterile fish juice using sensory and chemical analyses. Autoinducer 2 and two cyclic dipeptides (DKPs) including cyclo-(l-Pro-l-Leu) and cyclo-(l-Pro-l-Phe), no any AHLs, were detected in cell-free S. baltica culture. Interestingly, S.baltica02 had the highest QS activity among three spoilers of S. baltica. The production of biofilm, trimethylamines (TMA) and putrescine in these spoilers significantly increased in the presence of cyclo-(l-Pro-l-Leu), rather than cyclo-(l-Pro-l-Phe) and 4,5-dihydroxy-2,3-pentanedione (the AI-2 precursor, DPD). In accordance with the effect of signal molecules on the spoilage phenotype, exposure to exogenous cyclo-(l-Pro-l-Leu) was also showed to up-regulate the transcription levels of luxR, torA and ODC, and no effect of luxS indicated that S. baltica could sense cyclo-(l-Pro-l-Leu). In the fish homogenate, exogenous cyclo-(l-Pro-l-Leu) shortened lag phase durations and enhanced growth rates of the dominant bacteria, H2S producing bacteria, under refrigerated storage, while exogenous DPD retarded growth of competing bacteria, such as Enterobacteriaceae. Meanwhile, cyclo-(l-Pro-l-Leu) also promoted the accumulation of metabolites on the spoilage process of homogenate. S.baltica02 luxS mutant preliminarily proved that AI-2 might not play a signaling role in the spoilage. The present study suggested that the spoilage potential of S. baltica in P. crocea might be regulated by DKP-based quorum sensing.

  12. Evaluation of the spoilage potential of bacteria isolated from spoiled raw salmon (Salmo salar) fillets stored under modified atmosphere packaging.

    PubMed

    Macé, Sabrina; Joffraud, Jean-Jacques; Cardinal, Mireille; Malcheva, Mariya; Cornet, Josiane; Lalanne, Valérie; Chevalier, Frédérique; Sérot, Thierry; Pilet, Marie-France; Dousset, Xavier

    2013-01-01

    The spoilage potential of eight bacterial groups/species (Serratia spp., Hafnia alvei, Brochothrix thermosphacta, Carnobacterium maltaromaticum, Shewanella baltica, Lactococcus piscium, Photobacterium phosphoreum, "other Enterobacteriaceae" [containing one strain of Moellerella sp., Morganella sp. and Pectobacterium sp.]) isolated from spoiled raw salmon fillets stored under modified atmosphere packaging (MAP) was evaluated by inoculation into sterile raw salmon cubes followed by storage for 12days at 8°C. Microbial growth and sensory changes were monitored during the storage period. The dominant spoilage bacteria were C. maltaromaticum, H. alvei and P. phosphoreum. In order to further characterize their spoilage potential and to study the effect of their interactions, each of these 3 specific spoilage organisms (SSO) and two mixed-cultures, C. maltaromaticum/H. alvei and C. maltaromaticum/P. phosphoreum were tested in the sterile salmon model system using a combination of complementary methods: molecular (PCR-TTGE), sensory, chemical and conventional microbiological analyses. It was concluded that, in the mixed-culture inoculated samples, the dominant species determined the spoilage characteristics. The volatile fraction of P. phosphoreum inoculated samples was analyzed by solid-phase microextraction (SPME) followed by gas chromatography coupled to mass spectrometry (GC-MS). Among the specific volatile compounds present on P. phosphoreum spoiled inoculated samples, acetic acid was correlated with sensory analysis and can be proposed as a raw salmon spoilage marker.

  13. Broth and agar hop-gradient plates used to evaluate the beer-spoilage potential of Lactobacillus and Pediococcus isolates.

    PubMed

    Haakensen, M; Schubert, A; Ziola, B

    2009-03-15

    Identification of the beer-spoilage Lactobacillus and Pediococcus bacteria has largely taken two approaches; identification of spoilage-associated genes or identification of specific species of bacteria regardless of ability to grow in beer. The problem with these two approaches is that they are either overly inclusive (i.e., detect all bacteria of a given species regardless of spoilage potential) or overly selective (i.e., rely upon individual, putative spoilage-associated genes). Our goal was to design a method to assess the ability of Lactobacillus and Pediococcus to spoil beer that is independent of speciation or genetic background. In searching for a method by which to differentiate between beer-spoilage bacteria and bacteria that cannot grow in beer, we explored the ability of lactobacilli and pediococci isolates to grow in the presence of varying concentrations of hop-compounds and ethanol in broth medium versus on agar medium. The best method for differentiating between bacteria that can grow in beer and bacteria that do not pose a threat as beer-spoilage organisms was found to be a hop-gradient agar plate containing ethanol. This hop-gradient agar plate technique provides a rapid and simple solution to the dilemma of assessing the ability of Lactobacillus and Pediococcus isolates to grow in beer, and provides new insights into the different strategies used by these bacteria to survive under the stringent conditions of beer.

  14. Metabolism of lactic acid in fermented cucumbers by Lactobacillus buchneri and related species, potential spoilage organisms in reduced salt fermentations.

    PubMed

    Johanningsmeier, Suzanne D; McFeeters, Roger F

    2013-09-01

    Recent evidence suggests that Lactobacillus buchneri may play an important role in spoilage-associated secondary fermentation of cucumbers. Lactic acid degradation during fermented cucumber spoilage is influenced by sodium chloride (NaCl) concentration, pH, and presence of oxygen. Objectives were to evaluate these factors on lactic acid utilization by L. buchneri, and to compare the biochemical changes to those which occur during fermented cucumber spoilage. Effects of NaCl (0, 2, 4, and 6% w/w), pH (3.8 vs 5.0), and aerobic environment were investigated using fermented cucumber media (FC) inoculated with spoilage microorganisms. At pH 3.8, L. buchneri degraded lactic acid in all NaCl concentrations. The highest rate of lactic acid utilization occurred in FC with 2% NaCl (P < 0.05). Lactic acid utilization was nearly identical under aerobic and anaerobic conditions, indicating that oxygen does not influence lactate metabolism by L. buchneri. Lactic acid utilization was accompanied by increases in acetic acid and 1,2-propanediol, and Lactobacillus rapi was able to convert 1,2-propanediol to propionic acid and propanol. L. buchneri initiated spoilage in a wide range of environmental conditions that may be present in commercial cucumber fermentations, and L. rapi may act syntrophically with L. buchneri to produce the commonly observed spoilage metabolites.

  15. Characteristics of remixed fermentation dough and its influence on the quality of steamed bread.

    PubMed

    Li, Zhijian; Deng, Cui; Li, Haifeng; Liu, Changhong; Bian, Ke

    2015-07-15

    In this study, the effects of the amount of remixed flour on the properties of remixed fermentation dough and the quality of Chinese steamed breads were investigated. The hardness, chewiness and whiteness of steamed bread increased when the amount of remixed flour was higher than 10 g/100 g, whereas the specific volume of steamed bread significantly decreased. SEM analysis demonstrated that the gas cells of the steamed bread remained as a discrete spherical or oval-like entity only at 10 g/100 g level of remixed flour. Time-domain NMR showed that water migrated from T22 population to T21 population with increasing the amount of remixed flour. The XRD results indicated that starch in the steamed bread with remixed flour was gelatinized. A significant decrease of both the rate and extent of starch hydrolysis of the steamed bread was observed when flour was remixed.

  16. Effect of freezing and frozen storage of doughs on bread quality.

    PubMed

    Ribotta, P D; León, A E; Añón, M C

    2001-02-01

    The effects of freezing and storage in frozen conditions on bread quality, crumb properties, and aggregative behavior of glutenins were analyzed. The effect of different additives on bread quality was also studied. The results obtained showed that freezing and storage at -18 degrees C decreased the bread quality. Samples stored in frozen conditions supplemented with diacetyl-tartaric acid ester of monoglycerides, gluten, and guar gum produced breads of greater volume and more open crumb structure than those prepared with the base formulation (without additives). All additives analyzed increased the proof time. Crumb firmness increased with dough frozen storage and bread aging time at 4 degrees C. A decrease in the amount of glutenin subunits of high molecular mass was observed by electrophoresis analysis of the SDS-soluble proteins aggregates extracted from the frozen dough. This result suggested that the protein matrix of bread underwent depolymerization during storage in frozen conditions.

  17. Nutritional, amylolytic enzymes inhibition and antioxidant properties of bread incorporated with Stevia rebaudiana.

    PubMed

    Ruiz-Ruiz, Jorge C; Moguel-Ordoñez, Yolanda B; Matus-Basto, Angel J; Segura-Campos, Maira R

    2015-01-01

    Wheat bread with sucrose content replaced with different levels of stevia extract was compared with traditional wheat bread. The ability to reduce glucose intake was highlighted by performing enzymatic assays using α-amylase and α-glucosidase. Antioxidant activity was measured by determining the scavenging effect on α,α-diphenyl-β-picrylhydrazyl radical. In comparison with the control, the bread with stevia extract was softer and had lower microbial growth during the shelf-life study. The sensory test showed that the substitution of 50% stevia extract was more acceptable when comparing with all the quality characteristics. Regarding the nutritional contribution, the content of dietary fiber and digestible carbohydrates in the bread with stevia extract was higher and lower respectively, so caloric intake was significantly reduced. The results showed that the biological properties of Stevia rebaudiana extract were retained after the bread making process and that the proposed bread could be suitable as functional food in human nutrition.

  18. Effect of a Thermoascus aurantiacus thermostable enzyme cocktail on wheat bread qualitiy.

    PubMed

    Oliveira, D S; Telis-Romero, J; Da-Silva, R; Franco, C M L

    2014-01-15

    Thermophilic fungus Thermoascus aurantiacus (CBMAI 756) on solid-state fermentation using corncob as a nutrient source produces an enzyme pool with the potential to be used in bread making. In this paper, the use of this enzyme cocktail as a wheat bread improver was reported. Both products released by flour arabinoxylan degradation and bread quality were investigated. The main product released through enzyme activity after prolonged incubation was xylose indicating the presence of xylanase; however, a small amount of xylobiose and arabinose also confirmed the presence of xylosidase and α-l-arabinofuranosidase, respectively. Enzyme mixture "in vitro" mainly attacked water-unextractable arabinoxylan contributing to beneficial effect in bread making. The use of an optimal enzyme concentration (35U xylanase/100g of flour) increased specific volume (22%), reduced crumb firmness (25%), and reduced amylopectin retrogradation (17%) during bread storage. In conclusion, the enzyme cocktail produced by T. aurantiacus CBMAI 756 can improve wheat bread quality.

  19. Fungi: Strongmen of the Underground.

    ERIC Educational Resources Information Center

    Morrell, Patricia D.; Morrell, Jeffrey J.

    1999-01-01

    Presents an activity that stresses the role of fungi and decomposers, highlights the rapidity by which they complete this process, and allows students to experiment with ways to control the rate of decomposition. (CCM)

  20. Mitigation of the processing contaminant acrylamide in bread by reducing asparagine in the bread dough.

    PubMed

    Katsaiti, Tatiana; Granby, Kit

    2016-09-01

    Over the past few years there has been an increasing awareness regarding acrylamide (AAM) content of various foods. Although there are several relevant articles on AAM mitigation in industrially prepared products, the literature regarding homemade preparations is rather scarce. The objective of this study is to mitigate the AAM formation in baked buns made with 1:1 sifted wheat/wholegrain flour through the depletion of asparagine (ASN) in the bread dough. Using a full-factorial design, the effect of four factors (yeast amount, fermentation time, fermentation temperature and yeast types) was tested. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for AAM and its main precursor, ASN, determination. The resulting ASN depletion in the dough (68-89%) is significantly affected by fermentation time and yeast type, while AAM mitigation levels in the baked buns are significantly influenced by yeast amount, fermentation time and yeast type. The mean concentrations for each combination range between 5 and 15 µg kg(-)(1).

  1. Brewing spoilage Lactobacilli detected using monoclonal antibodies to bacterial surface antigens.

    PubMed

    Whiting, M S; Gares, S L; Ingledew, W M; Ziola, B

    1999-01-01

    A panel of thirteen monoclonal antibodies (Mabs) was assembled that reacts with surface antigens on eight of eleven Lactobacillus brewing spoilage organisms, including one or more of L. brevis, L. buchneri, L. casei-alactosus, L. plantarum, or unspeciated isolate(s). Immunoblotting was done to identify the antigens involved in Mab binding. Antigen stability in situ was tested by protease treatment and by surface antigen extraction of washed bacteria. Protease susceptibility of extracted surface antigens was also examined. In most cases, Lactobacillus surface antigens detected by the Mabs appear to be noncovalently bound proteins readily altered or removed from the bacterium by various environmental conditions. This research identifies brewing conditions that need to be tested to ascertain whether bacterial surface antigen-reactive Mabs can be used for the rapid, sensitive, and specific detection of Lactobacillus brewing spoilage organisms.

  2. Bacterial surface antigen-specific monoclonal antibodies used to detect beer spoilage pediococci.

    PubMed

    Whiting, M S; Ingledew, W M; Lee, S Y; Ziola, B

    1999-08-01

    Fourteen monoclonal antibodies (Mabs) were isolated that react with surface antigens of Pediococcus beer spoilage organisms, including P. damnosus, P. pentosaceous, P. acidilactici, and unspeciated isolates. Immunoblotting, enzyme immunoassays (EIAs) of protease- and neuraminidase-treated surface antigen extracts, carbohydrate competition EIAs, and cardiolipin EIAs were used to characterize the bacterial antigens involved in Mab binding. Antigen stability in situ was tested by protease treatment or surface antigen extraction of washed bacteria. In most cases, the Mabs bind to Pediococcus surface antigens that appear to be covalently bound cell wall polymers resistant to alteration or removal from the bacterial surface. These bacterial surface antigen reactive Mabs show good potential for rapid, sensitive, and specific immunoassay detection of Pediococcus beer spoilage organisms.

  3. Development of microbial spoilage and lipid and protein oxidation in rabbit meat.

    PubMed

    Nakyinsige, K; Sazili, A Q; Aghwan, Z A; Zulkifli, I; Goh, Y M; Abu Bakar, F; Sarah, S A

    2015-10-01

    This experiment aimed to determine microbial spoilage and lipid and protein oxidation during aerobic refrigerated (4°C) storage of rabbit meat. Forty male New Zealand white rabbits were slaughtered according to the Halal slaughter procedure. The hind limbs were used for microbial analysis while the Longissimus lumborum m. was used for determination of lipid and protein oxidation. Bacterial counts generally increased with aging time and the limit for fresh meat (10(8)cfu/g) was reached at d 7 postmortem. Significant differences in malondialdehyde content were observed after 3d of storage. The thiol concentration significantly decreased with increase in aging time. The band intensities of myosin heavy chain and troponin T significantly reduced with increased refrigerated storage while actin remained relatively stable. This study thus proposes protein oxidation as a potential deteriorative change in refrigerated rabbit meat along with microbial spoilage and lipid oxidation.

  4. Chewing bread: impact on alpha-amylase secretion and oral digestion.

    PubMed

    Joubert, Marianne; Septier, Chantal; Brignot, Hélène; Salles, Christian; Panouillé, Maud; Feron, Gilles; Tournier, Carole

    2017-02-22

    During chewing, saliva helps in preparing the food bolus by agglomerating the formed particles, and it initiates enzymatic food breakdown. However, limited information is actually available on the adaptation of saliva composition during the oral processing of complex foods, especially for foods that are sensitive to salivary enzymes. We addressed this question in the context of starch-based products and salivary alpha-amylase. The objectives were two-fold: (1) to determine if salivary alpha-amylase secretion can be modulated by the bread type and (2) to evaluate the contribution of the oral phase in bread enzymatic breakdown. Mouthfuls of three different wheat breads (industrial, artisan and whole-meal breads) were chewed by twelve subjects. Saliva samples were collected at rest and at different times corresponding to 33, 66 and 100% of the individual's chewing sequence. Alpha-amylase activity and total protein content were determined for all saliva samples that were collected. Additionally, the salivary maltose concentration was measured as a marker of bread enzymatic digestion. Boluses were collected at the swallowing time to evaluate the saliva uptake. Chewing industrial bread induced higher saliva uptake than the other breads despite a similar chewing duration. The evolution of salivary amylase activity tended to depend on the type of bread and was highly influenced by a large degree of inter- and intra-subject variability. The protein and maltose concentration steadily increased during chewing as a result of bread breakdown. The salivary protein concentration was mainly affected by the release of the water-soluble proteins of the bread. The salivary maltose concentration was found to be significantly lower for the whole-meal bread. When considering the weight of the mouthful, enzymatic breakdown was found to be most efficient for the breads ranking from industrial > artisan > whole-meal.

  5. Thermal Design, Analysis, and Testing of the Quench Module Insert Bread Board

    NASA Technical Reports Server (NTRS)

    Breeding, Shawn; Khodabandeh, Julia

    2002-01-01

    Contents include the following: Quench Module Insert (QMI) science requirements. QMI interfaces. QMI design layout. QMI thermal analysis and design methodology. QMI bread board testing and instrumentation approach. QMI thermal probe design parameters. Design features for gradient measurement. Design features for heated zone measurements. Thermal gradient analysis results. Heated zone analysis results. Bread board thermal probe layout. QMI bread board correlation and performance. Summary and conclusions.

  6. Fungi contamination of drinking water.

    PubMed

    Al-Gabr, Hamid Mohammad; Zheng, Tianling; Yu, Xin

    2014-01-01

    Aquatic fungi commonly infest various aqueous environments and play potentially crucial roles in nutrient and carbon cycling. Aquatic fungi also interact with other organisms to influence food web dynamics. In recent decades, numerous studies have been conducted to address the problem of microorganism contamination of water. The major concern has been potential effects on human health from exposure to certain bacteria, viruses, and protozoa that inhabit water and the microbial metabolites,pigments, and odors which are produced in the water, and their effects on human health and animals. Fungi are potentially important contaminants because they produce certain toxic metabolites that can cause severe health hazards to humans and animals. Despite the potential hazard posed by fungi, relatively few studies on them as contaminants have been reported for some countries.A wide variety of fungi species have been isolated from drinking water, and some of them are known to be strongly allergenic and to cause skin irritation, or immunosuppression in immunocompromised individuals (e.g., AIDS, cancer, or organ transplant patients). Mycotoxins are naturally produced as secondary metabolites by some fungi species, and exposure of humans or animals to them can cause health problems. Such exposure is likely to occur from dietary intake of either food,water or beverages made with water. However, mycotoxins, as residues in water,may be aerosolized when showering or when being sprayed for various purposes and then be subject to inhalation. Mycotoxins, or at least some of them, are regarded to be carcinogenic. There is also some concern that toxic mycotoxins or other secondary metabolites of fungi could be used by terrorists as a biochemical weapon by adding amounts of them to drinking water or non drinking water. Therefore, actions to prevent mycotoxin contaminated water from affecting either humans or animals are important and are needed. Water treatment plants may serve to partially

  7. Aliphatic hydrocarbons of the fungi.

    NASA Technical Reports Server (NTRS)

    Weete, J. D.

    1972-01-01

    Review of studies of aliphatic hydrocarbons which have been recently detected in the spores of phytopathogenic fungi, and are found to be structurally very similar to the alkanes of higher plants. It appears that the hydrocarbon components of the few mycelial and yeast forms reported resemble the distribution found in bacteria. The occurence and distribution of these compounds in the fungi is discussed. Suggested functional roles of fungal spore alkanes are presented.

  8. Methyl Halide Production by Fungi

    NASA Astrophysics Data System (ADS)

    Dailey, G. D.; Varner, R. K.; Blanchard, R. O.; Sive, B. C.; Crill, P. M.

    2005-12-01

    Methyl chloride (CH3Cl), methyl bromide (CH3Br) and methyl iodide (CH3I) are methyl halide gases that contribute significant amounts of halogen radicals to the atmosphere. In an effort to better understand the global budget of methyl halides and their impact on the atmosphere, we need to identify the natural sources in addition to the known anthropogenic sources of these compounds. We are investigating the role of fungi in the production of methyl halides in the soils and wetlands in southern New Hampshire, USA. Previous research has shown that wood decay fungi and ectomycorrhizal fungi, which are within a group of fungi called basidiomycetes, emit methyl halides. In our study, measurements of headspace gas extracted from flasks containing fungi grown in culture demonstrate that a variety of fungi, including basidiomycetes and non-basidiomycetes, emit methyl halides. Our research sites include four ecosystems: an agricultural field, a temperate forest, a fresh water wetland, and coastal salt marshes. We have collected and isolated fungi at each site by culturing tissue samples of fruiting bodies and plant material, by using wood baits, and from the direct culture of soil. We compared the rates of methyl halide emissions from the fungi in the four ecosystems. In addition, we measured emissions from previously assayed fungal isolates after reintroducing them to sterilized soils that were collected from their original environments. Fungal biomass was determined by substrate-induced respiration (SIR). The emission rate by the fungus was determined by a linear regression of the concentration of methyl halide in the sample headspace over time divided by the fungal biomass.

  9. Development of spoilage microbiota in beef stored in nisin activated packaging.

    PubMed

    Ercolini, Danilo; Ferrocino, Ilario; La Storia, Antonietta; Mauriello, Gianluigi; Gigli, Sergio; Masi, Paolo; Villani, Francesco

    2010-02-01

    The aim of this study was to assess the microbial populations causing the spoilage of chilled beef during storage and to evaluate the effect of the use of an antimicrobial packaging for the meat storage. A nisin activated antimicrobial packaging was developed by using a nisin, HCL and EDTA solution and used for the storage of beef cuts at 1 degrees C. The common spoilage related microbial groups were monitored during the storage of beef in activated and non activated plastic bags by using selective media. The use of the antimicrobial packaging caused an overall significant reduction of viable counts of Gram positive bacteria such as carnobacteria, lactic acid bacteria and Brochotrix thermosphacta whose development was inhibited for at least 11 days of storage compared to the control. Moreover, a 1-3 log cycles reduction of enterobacteria was also registered between 22 and 32 days of storage. The microbiota was assessed at species level by using Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis of 16S rRNA gene of DNA extracted directly from meat and from bulk cells from selective media plates and showed that the species occurring within the targeted microbial groups did not change according to storage conditions. In conclusion, the use of the nisin activated packaging reduced the number of spoilage populations but did not affect the species diversity. Improved antimicrobial packaging is needed, possibly coupled with vacuum storage, to possibly achieve a simultaneous inhibition of more spoilage microbial groups and to preserve the microbiological quality of beef during chilled storage.

  10. A standard bacterial isolate set for research on contemporary dairy spoilage.

    PubMed

    Trmčić, A; Martin, N H; Boor, K J; Wiedmann, M

    2015-08-01

    Food spoilage is an ongoing issue that could be dealt with more efficiently if some standardization and unification was introduced in this field of research. For example, research and development efforts to understand and reduce food spoilage can greatly be enhanced through availability and use of standardized isolate sets. To address this critical issue, we have assembled a standard isolate set of dairy spoilers and other selected nonpathogenic organisms frequently associated with dairy products. This publicly available bacterial set consists of (1) 35 gram-positive isolates including 9 Bacillus and 15 Paenibacillus isolates and (2) 16 gram-negative isolates including 4 Pseudomonas and 8 coliform isolates. The set includes isolates obtained from samples of pasteurized milk (n=43), pasteurized chocolate milk (n=1), raw milk (n=1), cheese (n=2), as well as isolates obtained from samples obtained from dairy-powder production (n=4). Analysis of growth characteristics in skim milk broth identified 16 gram-positive and 13 gram-negative isolates as psychrotolerant. Additional phenotypic characterization of isolates included testing for activity of β-galactosidase and lipolytic and proteolytic enzymes. All groups of isolates included in the isolate set exhibited diversity in growth and enzyme activity. Source data for all isolates in this isolate set are publicly available in the FoodMicrobeTracker database (http://www.foodmicrobetracker.com), which allows for continuous updating of information and advancement of knowledge on dairy-spoilage representatives included in this isolate set. This isolate set along with publicly available isolate data provide a unique resource that will help advance knowledge of dairy-spoilage organisms as well as aid industry in development and validation of new control strategies.

  11. Genome Sequence of the Food Spoilage Yeast Zygosaccharomyces bailii CLIB 213T.

    PubMed

    Galeote, Virginie; Bigey, Frédéric; Devillers, Hugo; Neuvéglise, Cécile; Dequin, Sylvie

    2013-08-22

    The ascomycetous yeast Zygosaccharomyces bailii is one of the most problematic spoilage yeasts in food and beverage industries, due to its exceptional resistance to various stresses. A better understanding of the molecular mechanisms underlying these stress resistance phenotypes might help develop strategies to improve food quality. Thus, we determined and annotated the genome sequence of the strain Z. bailii CLIB 213(T) (= CBS 680).

  12. Model approach to starch functionality in bread making.

    PubMed

    Goesaert, Hans; Leman, Pedro; Delcour, Jan A

    2008-08-13

    We used modified wheat starches in gluten-starch flour models to study the role of starch in bread making. Incorporation of hydroxypropylated starch in the recipe reduced loaf volume and initial crumb firmness and increased crumb gas cell size. Firming rate and firmness after storage increased for loaves containing the least hydroxypropylated starch. Inclusion of cross-linked starch had little effect on loaf volume or crumb structure but increased crumb firmness. The firming rate was mostly similar to that of control samples. Presumably, the moment and extent of starch gelatinization and the concomitant water migration influence the structure formation during baking. Initial bread firmness seems determined by the rigidity of the gelatinized granules and leached amylose. Amylopectin retrogradation and strengthening of a long-range network by intensifying the inter- and intramolecular starch-starch and possibly also starch-gluten interactions (presumably because of water incorporation in retrograded amylopectin crystallites) play an important role in firming.

  13. Rising dough and baking bread at the Australian synchrotron

    NASA Astrophysics Data System (ADS)

    Mayo, S. C.; McCann, T.; Day, L.; Favaro, J.; Tuhumury, H.; Thompson, D.; Maksimenko, A.

    2016-01-01

    Wheat protein quality and the amount of common salt added in dough formulation can have a significant effect on the microstructure and loaf volume of bread. High-speed synchrotron micro-CT provides an ideal tool for observing the three dimensional structure of bread dough in situ during proving (rising) and baking. In this work, the synchrotron micro-CT technique was used to observe the structure and time evolution of doughs made from high and low protein flour and three different salt additives. These experiments showed that, as expected, high protein flour produces a higher volume loaf compared to low protein flour regardless of salt additives. Furthermore the results show that KCl in particular has a very negative effect on dough properties resulting in much reduced porosity. The hundreds of datasets produced and analysed during this experiment also provided a valuable test case for handling large quantities of data using tools on the Australian Synchrotron's MASSIVE cluster.

  14. Vulnerability of Bread-Baskets to Weather Shocks

    NASA Astrophysics Data System (ADS)

    Gerber, J. S.; Ray, D. K.; West, P. C.; Foley, J. A.

    2013-12-01

    Many analyses of food security consider broad trends in food supply (crop production, crop use) and demand (changing diets, population growth.) However, if past shocks to the food system due to weather events (i.e. droughts) were to repeat themselves today, the resulting famines could be far more serious due to increased concentration of grain production in vulnerable bread-baskets, and decreased resilience of global and regional food systems (i.e. lower stocks, dependence on fewer crops). The present research project takes advantage of high-resolution historical weather datasets to assess probabilities of historically observed droughts repeating themselves in one or more of today's bread-basket regions. Using recently developed relationships between weather and crop yield, we consider the likelihood of region-wide crop failures under current conditions, and also under various climate scenarios.

  15. Genome interplay in the grain transcriptome of hexaploid bread wheat.

    PubMed

    Pfeifer, Matthias; Kugler, Karl G; Sandve, Simen R; Zhan, Bujie; Rudi, Heidi; Hvidsten, Torgeir R; Mayer, Klaus F X; Olsen, Odd-Arne

    2014-07-18

    Allohexaploid bread wheat (Triticum aestivum L.) provides approximately 20% of calories consumed by humans. Lack of genome sequence for the three homeologous and highly similar bread wheat genomes (A, B, and D) has impeded expression analysis of the grain transcriptome. We used previously unknown genome information to analyze the cell type-specific expression of homeologous genes in the developing wheat grain and identified distinct co-expression clusters reflecting the spatiotemporal progression during endosperm development. We observed no global but cell type- and stage-dependent genome dominance, organization of the wheat genome into transcriptionally active chromosomal regions, and asymmetric expression in gene families related to baking quality. Our findings give insight into the transcriptional dynamics and genome interplay among individual grain cell types in a polyploid cereal genome.

  16. Soft plastic bread packaging: lead content and reuse by families

    SciTech Connect

    Weisel, C.; Demak, M.; Marcus, S.; Goldstein, B.D. )

    1991-06-01

    The presence of lead in labels painted on soft plastic bread packaging was evaluated. Lead was detected on the outside of 17 of 18 soft plastic bread bags that were analyzed, with an average of 26 +/- 6 mg per bag with lead. Of 106 families questioned, 16 percent of respondents reported turning the bags inside out before reusing for food storage, thus putting food in contact with the lead paint. We estimate that a weak acid, such as vinegar, could readily leach 100 micrograms of lead from a painted plastic bag within 10 minutes. Further, lead and other metals painted on food packaging of any type becomes part of the municipal waste stream subject to incineration and to land-filling. The use of lead in packaging presents an unnecessary risk to public health.

  17. Noninvasive Qualitative and Quantitative Assessment of Spoilage Attributes of Chilled Pork Using Hyperspectral Scattering Technique.

    PubMed

    Zhang, Leilei; Peng, Yankun

    2016-08-01

    The objective of this research was to develop a rapid noninvasive method for quantitative and qualitative determination of chilled pork spoilage. Microbiological, physicochemical, and organoleptic characteristics such as the total viable count (TVC), Pseudomonas spp., total volatile basic-nitrogen (TVB-N), pH value, and color parameter L* were determined to appraise pork quality. The hyperspectral scattering characteristics from 54 meat samples were fitted by four-parameter modified Gompertz function accurately. Support vector machines (SVM) was applied to establish quantitative prediction model between scattering fitting parameters and reference values. In addition, partial least squares discriminant analysis (PLS-DA) and Bayesian analysis were utilized as supervised and unsupervised techniques for the qualitative identification of meat spoilage. All stored chilled meat samples were classified into three grades: "fresh," "semi-fresh," and "spoiled." Bayesian classification model was superior to PLS-DA with overall classification accuracy of 92.86%. The results demonstrated that hyperspectral scattering technique combined with SVM and Bayesian possessed a powerful capability for meat spoilage assessment rapidly and noninvasively.

  18. Diversity of the predominant spoilage bacteria in water-boiled salted duck during storage.

    PubMed

    Liu, Fang; Wang, Daoying; Du, Lihui; Zhu, Yongzhi; Xu, Weimin

    2010-06-01

    The spoilage microbiota in water-boiled salted duck during storage at 4 degrees C was determined using culture-dependent and independent methods. Analysis of the denaturing gradient gel electrophoresis (DGGE) patterns of PCR amplicons targeting the V3 region of the 16S rDNA and sequencing of the bands allowed profiling of the microbiota present in the duck. Community DNA extracts were prepared directly from water-boiled salted duck and from culturable bacterial fractions harvested from both MRS and PCA media. The spoilage bacteria mainly consisted of Staphylococcus saprophyticus, Macrococcus caseolyticus, Weissella, Halomonas sp. or Cobetia sp., and Exiguobacterium sp. based on sequencing and homology search of the DGGE bands. It appeared that both the bacterial counts and diversity increased during storage time. By plating method, bacterial counts in MRS agar increased from 10(4) to 10(8) CFU/g from day 1 to 10, while total bacterial counts in PCA agar reached 10(9) CFU/g after 10 d. Total of 14 strains isolated from PCA and MRS agar were identified as M. caseolyticus (2), S. saprophyticus (7), S. sciuri (1), W. paramesenteroides (2), and W. confusa (2) by 16S rDNA sequencing. The identification of the spoilage-related microbiota is helpful to better understand the bacteria ecology in water-boiled salted duck and may lead to the discovery of appropriate preservation strategies.

  19. Non-destructive detection of fish spoilage using a wireless basic volatile sensor.

    PubMed

    Bhadra, Sharmistha; Narvaez, Claudia; Thomson, Douglas J; Bridges, Greg E

    2015-03-01

    A hydrogel-pH-electrode based near-field passive volatile sensor is described for real-time monitoring of fish spoilage. The sensor employs a varactor-based LC resonator that can be interrogated remotely using inductive coupling. The sensor's resonant frequency varies in response to the basic volatile spoilage compounds (total volatile basic nitrogen, TVB-N) in the headspace of packaged fish. The sensor is shown to have a linear response to logarithm of the ammonia gas concentration with a detection limit of 0.001 mg L(-1) (1.5 ppm). Trials on tilapia at 24 °C and 4 °C, employing direct comparison of sensor measurements with microbial analysis, indicate that the sensor response is correlated with the bacterial growth pattern in fish samples. It is shown that the sensor can distinctly identify when the product rejection level (10(7) cfu g(-1) bacterial population) occurs for both 24 °C and 4 °C storage conditions. This demonstrates a potential for real-time monitoring of fish spoilage. The wireless sensor is suited to embedding in packaging material and does not require an integrated circuit, making it amenable to inexpensive mass production using printed electronic technology.

  20. Tracking heat-resistant, cold-thriving fluid milk spoilage bacteria from farm to packaged product.

    PubMed

    Huck, J R; Sonnen, M; Boor, K J

    2008-03-01

    Control of psychrotolerant endospore-forming spoilage bacteria, particularly Bacillus and Paenibacillus spp., is economically important to the dairy industry. These microbes form endospores that can survive high-temperature, short-time pasteurization; hence, their presence in raw milk represents a major potential cause of milk spoilage. A previously developed culture-dependent selection strategy and an rpoB sequence-based subtyping method were applied to bacterial isolates obtained from environmental samples collected on a New York State dairy farm. A total of 54 different rpoB allelic types putatively identified as Bacillus (75% of isolates), Paenibacillus (24%), and Sporosarcina spp. (1%) were identified among 93 isolates. Assembly of a broader data set, including 93 dairy farm isolates, 57 raw milk tank truck isolates, 138 dairy plant storage silo isolates, and 336 pasteurized milk isolates, identified a total of 154 rpoB allelic types, representing an extensive diversity of Bacillus and Paenibacillus spp. Our molecular subtype data clearly showed that certain endospore-forming bacterial subtypes are present in the dairy farm environment as well as in the processing plant. The potential for entry of these ubiquitous heat-resistant spoilage organisms into milk production and processing systems, from the dairy farm to the processing plant, represents a considerable challenge that will require a comprehensive farm-to-table approach to fluid milk quality.

  1. Purification and partial characterization of an antigen specific to Lactobacillus brevis strains with beer spoilage activity.

    PubMed

    Yasui, T; Yoda, K

    1997-06-15

    Certain Lactobacillus brevis strains are resistant to hop-derived compounds such as isohumulone and are able to grow in beer. In this study, we raised an antiserum against our beer spoilage laboratory strain L. brevis 578 which reacted with 23 of 24 beer spoilers and two of 13 non-spoilers in precipitation reactions using 0.5 M NaOH cell extracts. This specific antigen to the beer spoilage L. brevis strains (SABSL) was demonstrated to be located beneath the S-layer proteins by agglutination reactions using S-layer protein-stripped cells obtained by treatment with 0.1 M NaOH. SABSL was purified using an affinity column coupled with an antibody against SABSL. The purified antigen was hydrolyzed with 2 M HCl and the hydrolyzate was analyzed by thin-layer chromatography and enzymatic analysis. The results showed that SABSL contains glycerol, phosphate, glycerophosphate, D-galactose and D-glucose. D-Galactose and D-glucose accounted for 4.7% and 0.1% of the composition, respectively. Melibiose, but not mannose, inhibited the precipitation reaction. Intense precipitation reactions were obtained with fractions which did not bind to the ConA-column. These results indicate that the immunodominant component of the SABSL is galactose and the SABSL determinant is most probably a galactosylated glycerol teichoic acid. The antiserum raised against the beer spoilage strain L. brevis 578 could distinguish between Pediococcus beer spoilers and non-spoilers in precipitation reactions.

  2. Spoilage potential characterization of Shewanella and Pseudomonas isolated from spoiled large yellow croaker (Pseudosciaena crocea).

    PubMed

    Ge, Y; Zhu, J; Ye, X; Yang, Y

    2017-01-01

    Ten strains were isolated from a spoiled large yellow croaker (Pseudosciaena crocea). All of them were able to grow aerobically from 4 to 30°C, and reduce trimethylamine-N-oxide to trimethylamine (TMA) and produce H2 S except SB01, PF05 and PF07. Biochemical characterization and phylogenetic analysis of 16S rRNA gene showed that eight H2 S-producing isolates were closely related to Shewanella baltica, and two isolates PF05 and PF07 were identified as Pseudomonas fluorescens and Pseudomonas fragi respectively. However, of the eight Shewanella, seven isolates cluster with S. baltica and one with Shewanella glacialipiscicola based on the analysis of the gyrB gene. Shewanella baltica also had the ability to produce biogenic amines, while two Pseudomonas had high activities of proteinase and lipase, and failed to produce TMA and biogenic amines. In spoilage potential evaluation, the TVB-N value of S. baltica was significantly higher than that of Pseudomonas in sterile fish juice, although its growth was slower than Pseudomonas. Therefore, this work demonstrated that S. baltica was able to cause rapid and strong spoilage and was therefore identified as a specific spoilage organism in refrigerated P. crocea.

  3. Characterisation of microbial deep spoilage in Iberian dry-cured ham.

    PubMed

    Martín, Alberto; Benito, María J; Hernández, Alejandro; Pérez-Nevado, Francisco; Córdoba, Juan J; Córdoba, María G

    2008-04-01

    The purpose of this work was to investigate the micro-organisms involved in overlooked "bone taint" spoilage of dry-cured Iberian hams. The physico-chemical characteristics of spoiled hams with 12 and 24 months of ripening, showing initial signs of alteration, were analyzed and their correlations with microbial counts studied. The spoilage potential of different microbial groups was assessed by the relationship between the microbial counts and the proteolysis level of spoilage as observed in the degradation of myofribrillar and sarcoplasmic protein fractions and in the changes in free amino acids. Non-enteric gram-negative bacteria (NEGN) were the dominant microbial group, showing a positive correlation with the moisture of spoiled hams. The Catalase-positive cocci (GPCP) growth was favoured by high NaCl concentrations in the spoiled hams, whereas the counts of Enterobacteriaceae were negatively affected by high NaCl concentration. The highest proteolytic microorganisms were the Gram-negative microbial groups playing Enterobacteriaceae a major role in the undesirable changes of the texture properties of the spoiled hams. With respect to the sensorial analysis, a synergy between NEGN and GPCP was observed in most of the strongly spoiled samples.

  4. Sour rot-damaged grapes are sources of wine spoilage yeasts.

    PubMed

    Barata, André; González, Sara; Malfeito-Ferreira, Manuel; Querol, Amparo; Loureiro, Virgílio

    2008-11-01

    Yeast species of sound and sour rot-damaged grapes were analysed during fermentation and grape ripening in the vineyard, using general and selective culture media. During 2003 and 2004 vintages, microvinifications were carried out with sound grapes to which different amounts of grapes with sour rot were added. The wine spoilage species Zygosaccharomyces bailii was only recovered during fermentations with sour rot, reaching 5.00 log CFU mL(-1) (2003) and 2.48 log CFU mL(-1) (2004) at the end of fermentation. The study of yeast populations during the sour rot ripening process (2005 vintage) showed that the veraison-damaged grapes always exhibited higher total yeast counts and a much greater diversity of species. From a total of 22 ascomycetous species, 17 were present only in damaged grapes. The most frequent species were Issatchenkia occidentalis and Zygoascus hellenicus. The spoilage species Z. bailii and Zygosaccharomyces bisporus were consistently isolated exclusively from damaged grapes. This work demonstrates that one of the most dangerous wine spoilage species, Z. bailii, is strongly associated with sour rot grapes and survives during fermentation with Saccharomyces cerevisiae. The use of selective media provides a more accurate characterization of grape contamination species.

  5. Spoilage of foods monitored by native fluorescence spectroscopy with selective excitation wavelength

    NASA Astrophysics Data System (ADS)

    Pu, Yang; Wang, Wubao; Alfano, Robert R.

    2015-03-01

    The modern food processing and storage environments require the real-time monitoring and rapid microbiological testing. Optical spectroscopy with selective excitation wavelengths can be the basis of a novel, rapid, reagent less, noncontact and non-destructive technique for monitoring the food spoilage. The native fluorescence spectra of muscle foods stored at 2-4°C (in refrigerator) and 20-24°C (in room temperature) were measured as a function of time with a selective excitation wavelength of 340nm. The contributions of the principal molecular components to the native fluorescence spectra of meat were measured spectra of each fluorophore: collagen, reduced nicotinamide adenine dinucleotide (NADH), and flavin. The responsible components were extracted using a method namely Multivariate Curve Resolution with Alternating Least-Squares (MCR-ALS). The native fluorescence combined with MCR-ALS can be used directly on the surface of meat to produce biochemically interpretable "fingerprints", which reflects the microbial spoilage of foods involved with the metabolic processes. The results show that with time elapse, the emission from NADH in meat stored at 24°C increases much faster than that at 4°C. This is because multiplying of microorganisms and catabolism are accompanied by the generation of NADH. This study presents changes of relative content of NADH may be used as criterion for detection of spoilage degree of meat using native fluorescence spectroscopy.

  6. Molecular characterization of spoilage bacteria as a means to observe the microbiological quality of carrot.

    PubMed

    Kahala, Minna; Blasco, Lucia; Joutsjoki, Vesa

    2012-03-01

    This study characterized the bacteria causing decay of carrots during storage and marketing. Spoilage strains were identified by 16S-amplified rDNA restriction analysis and intergenic transcribed spacer-PCR-restriction fragment length polymorphism (ITS-PCR-RFLP). Genotypic fingerprinting by RFLP-pulsed-field gel electrophoresis was used to assess the genetic diversity of the isolates. A total of 252 Pseudomonas isolates from carrots were identified and classified into eight separate groups. Most strains belonged to group A (Pseudomonas fluorescens, Pseudomonas marginalis, and Pseudomonas veronii) and group B (Pseudomonas putida). The strains identified as Pectobacterium carotovorum subsp. carotovorum, Pectobacterium atrosepticum, Dickeya chrysanthemi, and Erwinia rhapontici were distinguished by ITS-PCR-RFLP. All isolates belonging to the genera Pectobacterium and Erwinia were responsible for carrot spoilage. This work has led to the development of new strategies for the identification and genotyping of vegetable-spoiling strains of Pseudomonas, Pectobacterium, and Erwinia. This is also the first report describing the occurrence of carrot-spoiling E. rhapontici. Early recognition of spoilage bacteria in vegetables is important for the implementation of effective handling strategies. Pectolytic bacteria may cause considerable financial losses because they account for a large proportion of bacterial rot of fruits and vegetables during storage, transit, and marketing.

  7. TdKT, a new killer toxin produced by Torulaspora delbrueckii effective against wine spoilage yeasts.

    PubMed

    Villalba, María Leticia; Susana Sáez, Julieta; Del Monaco, Silvana; Lopes, Christian Ariel; Sangorrín, Marcela Paula

    2016-01-18

    Microbiological spoilage is a major concern throughout the wine industry, and control tools are limited. This paper addresses the identification and partial characterization of a new killer toxin from Torulaspora delbrueckii with potential biocontrol activity of Brettanomyces bruxellensis, Pichia guilliermondii, Pichia manshurica and Pichia membranifaciens wine spoilage. A panel of 18 different wine strains of T. delbrueckii killer yeasts was analysed, and the strain T. delbrueckii NPCC 1033 (TdKT producer) showed a significant inhibitory effect on the growth of all different spoilage yeasts evaluated. The TdKT toxin was then subjected to a partial biochemical characterization. Its estimated molecular weight was N30 kDa and it showed glucanase and chitinase enzymatic activities. The killer activity was stable between pH 4.2 and 4.8 and inactivated at temperature above 40 °C. Pustulan and chitin — but not other cell wall polysaccharides — prevented sensitive yeast cells from being killed by TdKT, suggesting that those may be the first toxin targets in the cell wall. TdKT provoked an increase in necrosis cell death after 3 h treatment and apoptotic cell death after 24 h showing time dependence in its mechanisms of action. Killer toxin extracts were active at oenological conditions, confirming their potential use as a biocontrol tool in winemaking.

  8. Evaluation of dough rheological properties and bread texture of pearl millet-wheat flour mix.

    PubMed

    Maktouf, Sameh; Jeddou, Khawla Ben; Moulis, Claire; Hajji, Hejer; Remaud-Simeon, Magali; Ellouz-Ghorbel, Raoudha

    2016-04-01

    This study was undertaken with the objective of formulating composite bread using pearl millet (Pennisetum glaucum) and wheat (Triticum aestivum) flours . Rheological and bread making properties of composite flours were evaluated. Mixolab results revealed torque increased and dough stability time decreased upon incorporation of pearl millet flour in wheat flour. The incorporation of millet flour at optimum level (5 %) led to an increase of the dough strength (W) and the elasticity-to-extensibility ratio (P/L) by 31 % and 65 % respectively. The bread texture and volume were also improved. These findings indicated the potentiality of using millet flour in bread making.

  9. Understanding gluten-free dough for reaching breads with physical quality and nutritional balance.

    PubMed

    Matos, María E; Rosell, Cristina M

    2015-03-15

    In the last decade the development of gluten-free foodstuffs has attracted great attention as a result of better diagnoses of coeliac disease and a greater knowledge of the relationship between gluten-free products and health. The increasing interest has prompted extensive research into the development of gluten-free foodstuffs that resemble gluten-containing foods. This review aims to provide some insights on dough functionality and process conditions regarding bread quality and to point out recent research dealing with the nutritional composition of those products. Gluten-free dough results from the combination of different ingredients, additives, and the processing aids required for building up network structures responsible for bread quality. Some relationships between dough rheology and bread characteristics were established to identify possible predictor parameters. Regarding bread-making processes, the impact of mixing, dough treatment and baking is stated. Nutritional quality is an important asset when developing gluten-free breads, and different strategies for improving it are reviewed. Gluten-free bread quality is dependent on ingredients and additives combination, but also processing can provide a way to improve bread quality. Nutritive value of the gluten-free breads must be always in mind when setting up recipes, for obtaining nutritionally balanced bread with adequate glycaemic index.

  10. Effect of spelt wheat flour and kernel on bread composition and nutritional characteristics.

    PubMed

    Skrabanja, V; Kovac, B; Golob, T; Liljeberg Elmståhl, H G; Björck, I M; Kreft, I

    2001-01-01

    Spelt wheat seeds (Triticum aestivum subsp. spelta cv. Ostro) were used to obtain white spelt flour (64.5% yield), wholemeal spelt flour (100% yield), and scalded spelt wheat kernels. From these materials, white spelt wheat bread (WSB), wholemeal spelt wheat bread (WMSB), and spelt wheat bread with scalded spelt wheat kernels (SSKB) were made and were compared to the reference white wheat bread (WWB). The spelt wheat flours and breads contained more proteins in comparison to wheat flour and bread. Among the samples the highest rate of starch hydrolysis was noticed in WSB. During the first 30 min of incubation this particular bread was shown to have significantly more (P < 0.05) rapidly digestible starch than the WMSB and later on also more starch than in WWB and SSKB, respectively. The WMSB had the lowest hydrolysis index (HI = 95.7). However, the result did not differ significantly from that in the reference common wheat bread. On the other hand, the most refined spelt wheat flour resulted in a bread product (WSB) that was statistically withdrawn (P < 0.05) as one with the highest HI (112.6).

  11. Modelling the effects of orange pomace using response surface design for gluten-free bread baking.

    PubMed

    O'Shea, N; Rößle, C; Arendt, E; Gallagher, E

    2015-01-01

    The development of gluten-free bread creates many challenges; producing bread that will match the properties of its wheat counterpart can be difficult. Fruit by-products are know from literature to contain a high level of dietary fibre which could improve the bread properties and fibre contents of gluten-free bread. Therefore, a mathematical design was created; three variables were identified from preliminary tests (water (85-100% flour weight, OP 0-8% flour weight and proofing time 35-100 min) as being crucial in the development of acceptable bread. Results illustrated longer proofing times (p<0.05) and lower orange pomace levels (OP) (p<0.001) produced a bread with a greater specific volume. OP had the most significant (p<0.0001) effect on hardness at 2h and 24h post-baking. The optimised formulation was calculated to contain 5.5% OP, 94.6% water and a proofing time of 49 min. Total fibre content of the control bread (2.1%) was successfully increased t o 3.9% in the OP containing bread. Substituting gluten-free flours with orange pomace flour can help improve the total dietary intake of a coeliac while not negating on the quality properties of the bread.

  12. Effect of Hydrocolloids and Emulsifiers on Baking Quality of Composite Cassava-Maize-Wheat Breads

    PubMed Central

    Eduardo, Maria; Ahrné, Lilia

    2014-01-01

    Cassava is widely available worldwide but bread quality is impaired when cassava is used in the bread formulation. To overcome this problem, different improvers were tested in the preparation of composite cassava-maize-wheat (CMW) breads. Emulsifiers, diacetyl tartic acid ester of monoglycerides (DATEM), sodium stearoyl-2-lactylate (SSL), and lecithin (LC); and hydrocolloids, carboxymethylcellulose (CMC) and high-methylated pectin (HM pectin) were added during dough preparation of the composite flours (cassava-maize-wheat, 40 : 10 : 50). Each emulsifier was tested in combination with the hydrocolloids at levels of 0.1, 0.3, and 0.5% while hydrocolloids were used at a level of 3%. Bread quality attributes such as specific loaf volume, crust colour, crumb moisture, and firmness were measured. The specific volume of the fresh breads significantly improved with the addition of hydrocolloids (7.5 and 13%) and in combination with emulsifiers (from 7.9 to 27%) compared with bread produced without improvers. A significant improvement of brownness index and firmness of the composite flours breads was achieved with the addition of hydrocolloids and emulsifiers. The results show that emulsifiers and hydrocolloids can significantly improve the baking quality of CMW breads and thereby enhance the potential for using locally produced flours in bread baking. PMID:26904634

  13. Effect of Hydrocolloids and Emulsifiers on Baking Quality of Composite Cassava-Maize-Wheat Breads.

    PubMed

    Eduardo, Maria; Svanberg, Ulf; Ahrné, Lilia

    2014-01-01

    Cassava is widely available worldwide but bread quality is impaired when cassava is used in the bread formulation. To overcome this problem, different improvers were tested in the preparation of composite cassava-maize-wheat (CMW) breads. Emulsifiers, diacetyl tartic acid ester of monoglycerides (DATEM), sodium stearoyl-2-lactylate (SSL), and lecithin (LC); and hydrocolloids, carboxymethylcellulose (CMC) and high-methylated pectin (HM pectin) were added during dough preparation of the composite flours (cassava-maize-wheat, 40 : 10 : 50). Each emulsifier was tested in combination with the hydrocolloids at levels of 0.1, 0.3, and 0.5% while hydrocolloids were used at a level of 3%. Bread quality attributes such as specific loaf volume, crust colour, crumb moisture, and firmness were measured. The specific volume of the fresh breads significantly improved with the addition of hydrocolloids (7.5 and 13%) and in combination with emulsifiers (from 7.9 to 27%) compared with bread produced without improvers. A significant improvement of brownness index and firmness of the composite flours breads was achieved with the addition of hydrocolloids and emulsifiers. The results show that emulsifiers and hydrocolloids can significantly improve the baking quality of CMW breads and thereby enhance the potential for using locally produced flours in bread baking.

  14. Insights into bread melanoidins: fate in the upper digestive tract and impact on the gut microbiota using in vitro systems.

    PubMed

    Helou, Cynthia; Denis, Sylvain; Spatz, Madeleine; Marier, David; Rame, Véronique; Alric, Monique; Tessier, Frédéric J; Gadonna-Widehem, Pascale

    2015-12-01

    Bread melanoidins are heterogeneous, nitrogen-containing, brown macromolecules generated during the last stages of the Maillard reaction in bread. The aim of this study was to investigate the impact and fate of these bread melanoidins in the human gastrointestinal tract using in vitro systems. Batch systems as well as the TNO gastrointestinal tract were used for studying the digestion of various bread samples. These samples included bread crumb, bread crust and two bread-crust-simulating models: a fiber-free model (gluten, starch and glucose heated together) and its control, free of Maillard reaction products (gluten heated separately than starch and glucose). Furthermore, the impact of these two bread-crust-simulating models on the gut microbiota was assessed using a static anaerobic batch system. Bread melanoidins from bread crust and its model were shown to be partially digested by amylases and proteases, suggesting that these melanoidins have peptidic as well as glycosidic bonds in their skeleton. The impact of bread melanoidins from the bread-crust-simulating models and their digestion products on the gut microbiota revealed an individual-dependent response for most flora except for enterobacteria. This flora decreased by -22%, -48% & -100% depending on the individual. Thus, bread melanoidins seem to exert an anti-inflammatory effect by inhibiting enterobacteria.

  15. Influence of dextran-producing Weissella cibaria on baking properties and sensory profile of gluten-free and wheat breads.

    PubMed

    Wolter, Anika; Hager, Anna-Sophie; Zannini, Emanuele; Czerny, Michael; Arendt, Elke K

    2014-02-17

    Breads based on gluten-free buckwheat, quinoa, sorghum and teff flours were produced with addition of 20% sourdough fermented with exopolysaccharide (EPS) producing Weissella cibaria MG1. Wheat bread was baked as a reference. Dough rheology, bread quality parameters and sensory properties of the sourdough-containing breads were compared to sourdough non-containing control breads of the respective flour. The specific volume remained unaffected by sourdough application. In buckwheat, sorghum, teff and wheat sourdough breads acidification increased crumb porosity compared to control breads. Crumb hardness was significantly reduced in buckwheat (-122%), teff (-29%), quinoa (-21%) and wheat sourdough breads (-122%). The staling rate was significantly reduced in buckwheat, teff and wheat sourdough breads. Water activity of the sourdough containing bread crumb was not influenced by the presence of EPS. Due to the presence of exopolysaccharides (EPS) and influence of acidification, the dough strength, AF, as measured by oscillation tests decreased significantly in sourdough-containing buckwheat, sorghum and wheat dough, but increased in sourdough-containing quinoa and teff dough. Microbial shelf-life was significantly prolonged neither for gluten-free sourdough nor for wheat sourdough breads. Scanning electron microscopy of control and sourdough bread crumbs did not show differences concerning structural starch features. In addition, the aroma of most bread was not improved by sourdough addition.

  16. Induced Mutations for Improving Production on Bread and Durum Wheat

    SciTech Connect

    Stamo, Ilirjana; Ylli, Ariana; Dodbiba, Andon

    2007-04-23

    Wheat is a very important crop and has been bred for food and its improvement is continuous from cross-breeding. Radiation and chemically induced mutations have provided variability in selection for novel varieties. Four bread and one durum wheat cultivars were exposed to gamma rays, Cs 137 with doses 10, 15 and 20 krad (2000 seeds of each dose and cultivars). We have isolated mutant plants with height reduced and on cv Progress spike without chaff.

  17. Kinetics of bread crumb hydration as related to porous microstructure.

    PubMed

    Mathieu, Vincent; Monnet, Anne-Flore; Jourdren, Solenne; Panouillé, Maud; Chappard, Christine; Souchon, Isabelle

    2016-08-10

    During oral processing and throughout the digestion process, hydration mechanisms have a key influence on the functional properties of food. This is the case with bread, for which hydration may affect the kinetics of starch hydrolysis as well as taste, aroma and texture perceptions. In this context, the aim of the present study is to understand how crumb porous micro-architecture impacts hydration kinetics. Four types of French baguettes were considered, varying in structure and/or compositions. An experimental set-up was developed for the real-time measurement of water uptake in crumb samples. Mathematical models were then fitted to extract quantitative parameters of use for the description and the understanding of experimental observations. Finally, bread crumb samples were analyzed before and after hydration through X-ray micro-computed tomography for the assessment of crumb micro-architectural properties. Distinct hydration behaviors were observed for the four types of bread. Higher hydration rates and capacities were reported for industrial baguettes (highest porosity) compared to denser semi-industrial, whole wheat and traditional baguettes. However, crumb porosity alone is not sufficient to predict hydration behavior. This study made it possible to point out the importance of capillary action in crumb hydration mechanisms, with a strong role of cells with diameters of 2 mm and below. The high density of these small cells generates high interconnection probabilities that may have an impact both on crumb hydration duration and capacity. As a consequence, accounting for microstructural features resulting from bread formulation may provide useful leverages for the control of functional properties.

  18. Fungi producing significant mycotoxins.

    PubMed

    2012-01-01

    Mycotoxins are secondary metabolites of microfungi that are known to cause sickness or death in humans or animals. Although many such toxic metabolites are known, it is generally agreed that only a few are significant in causing disease: aflatoxins, fumonisins, ochratoxin A, deoxynivalenol, zearalenone, and ergot alkaloids. These toxins are produced by just a few species from the common genera Aspergillus, Penicillium, Fusarium, and Claviceps. All Aspergillus and Penicillium species either are commensals, growing in crops without obvious signs of pathogenicity, or invade crops after harvest and produce toxins during drying and storage. In contrast, the important Fusarium and Claviceps species infect crops before harvest. The most important Aspergillus species, occurring in warmer climates, are A. flavus and A. parasiticus, which produce aflatoxins in maize, groundnuts, tree nuts, and, less frequently, other commodities. The main ochratoxin A producers, A. ochraceus and A. carbonarius, commonly occur in grapes, dried vine fruits, wine, and coffee. Penicillium verrucosum also produces ochratoxin A but occurs only in cool temperate climates, where it infects small grains. F. verticillioides is ubiquitous in maize, with an endophytic nature, and produces fumonisins, which are generally more prevalent when crops are under drought stress or suffer excessive insect damage. It has recently been shown that Aspergillus niger also produces fumonisins, and several commodities may be affected. F. graminearum, which is the major producer of deoxynivalenol and zearalenone, is pathogenic on maize, wheat, and barley and produces these toxins whenever it infects these grains before harvest. Also included is a short section on Claviceps purpurea, which produces sclerotia among the seeds in grasses, including wheat, barley, and triticale. The main thrust of the chapter contains information on the identification of these fungi and their morphological characteristics, as well as factors

  19. Dynamics of the Saccharomyces cerevisiae transcriptome during bread dough fermentation.

    PubMed

    Aslankoohi, Elham; Zhu, Bo; Rezaei, Mohammad Naser; Voordeckers, Karin; De Maeyer, Dries; Marchal, Kathleen; Dornez, Emmie; Courtin, Christophe M; Verstrepen, Kevin J

    2013-12-01

    The behavior of yeast cells during industrial processes such as the production of beer, wine, and bioethanol has been extensively studied. In contrast, our knowledge about yeast physiology during solid-state processes, such as bread dough, cheese, or cocoa fermentation, remains limited. We investigated changes in the transcriptomes of three genetically distinct Saccharomyces cerevisiae strains during bread dough fermentation. Our results show that regardless of the genetic background, all three strains exhibit similar changes in expression patterns. At the onset of fermentation, expression of glucose-regulated genes changes dramatically, and the osmotic stress response is activated. The middle fermentation phase is characterized by the induction of genes involved in amino acid metabolism. Finally, at the latest time point, cells suffer from nutrient depletion and activate pathways associated with starvation and stress responses. Further analysis shows that genes regulated by the high-osmolarity glycerol (HOG) pathway, the major pathway involved in the response to osmotic stress and glycerol homeostasis, are among the most differentially expressed genes at the onset of fermentation. More importantly, deletion of HOG1 and other genes of this pathway significantly reduces the fermentation capacity. Together, our results demonstrate that cells embedded in a solid matrix such as bread dough suffer severe osmotic stress and that a proper induction of the HOG pathway is critical for optimal fermentation.

  20. Dynamics of the Saccharomyces cerevisiae Transcriptome during Bread Dough Fermentation

    PubMed Central

    Aslankoohi, Elham; Zhu, Bo; Rezaei, Mohammad Naser; Voordeckers, Karin; De Maeyer, Dries; Marchal, Kathleen; Dornez, Emmie

    2013-01-01

    The behavior of yeast cells during industrial processes such as the production of beer, wine, and bioethanol has been extensively studied. In contrast, our knowledge about yeast physiology during solid-state processes, such as bread dough, cheese, or cocoa fermentation, remains limited. We investigated changes in the transcriptomes of three genetically distinct Saccharomyces cerevisiae strains during bread dough fermentation. Our results show that regardless of the genetic background, all three strains exhibit similar changes in expression patterns. At the onset of fermentation, expression of glucose-regulated genes changes dramatically, and the osmotic stress response is activated. The middle fermentation phase is characterized by the induction of genes involved in amino acid metabolism. Finally, at the latest time point, cells suffer from nutrient depletion and activate pathways associated with starvation and stress responses. Further analysis shows that genes regulated by the high-osmolarity glycerol (HOG) pathway, the major pathway involved in the response to osmotic stress and glycerol homeostasis, are among the most differentially expressed genes at the onset of fermentation. More importantly, deletion of HOG1 and other genes of this pathway significantly reduces the fermentation capacity. Together, our results demonstrate that cells embedded in a solid matrix such as bread dough suffer severe osmotic stress and that a proper induction of the HOG pathway is critical for optimal fermentation. PMID:24056467

  1. Bread, beer and wine: Saccharomyces cerevisiae diversity reflects human history.

    PubMed

    Legras, Jean-Luc; Merdinoglu, Didier; Cornuet, Jean-Marie; Karst, Francis

    2007-05-01

    Fermented beverages and foods have played a significant role in most societies worldwide for millennia. To better understand how the yeast species Saccharomyces cerevisiae, the main fermenting agent, evolved along this historical and expansion process, we analysed the genetic diversity among 651 strains from 56 different geographical origins, worldwide. Their genotyping at 12 microsatellite loci revealed 575 distinct genotypes organized in subgroups of yeast types, i.e. bread, beer, wine, sake. Some of these groups presented unexpected relatedness: Bread strains displayed a combination of alleles intermediate between beer and wine strains, and strains used for rice wine and sake were most closely related to beer and bread strains. However, up to 28% of genetic diversity between these technological groups was associated with geographical differences which suggests local domestications. Focusing on wine yeasts, a group of Lebanese strains were basal in an F(ST) tree, suggesting a Mesopotamia-based origin of most wine strains. In Europe, migration of wine strains occurred through the Danube Valley, and around the Mediterranean Sea. An approximate Bayesian computation approach suggested a postglacial divergence (most probable period 10,000-12,000 bp). As our results suggest intimate association between man and wine yeast across centuries, we hypothesize that yeast followed man and vine migrations as a commensal member of grapevine flora.

  2. Recognition of Bread Key Odorants by Using Polymer Coated QCMs

    NASA Astrophysics Data System (ADS)

    Nakai, Takashi; Kouno, Shinji; Hiruma, Naoya; Shuzo, Masaki; Delaunay, Jean-Jacques; Yamada, Ichiro

    Polyisobutylene (PIB) polymer and methylphenylsiloxane (25%) diphenylsiloxane (75%) copolymer (OV25) were coated on Quartz Crystal Microbalance (QCM) sensors and used in recognition of bread key odorants. Representative compounds of key roasty odorants of bread were taken as 3-acetylpyridine and benzaldehyde, and representative key fatty odorants were hexanal and (E)-2-nonenal. Both OV25- and PIB-coated QCM fabricated sensors could detect concentration as low as 0.9 ppm of 3-acetylpyridine and 1.2 ppm of (E)-2-nonenal. The sensitivity to 3-acetylpyridine of the OV25-coated QCM was about 1000 times higher than that of ethanol, the major interference compound in bread key odorant analysis. Further, the OV25-coated QCM response was 5-6 times and 2-3 times larger than that of the PIB-coated QCM when exposed to roasty odorants and to fatty odorants, respectively. The difference in sensitivity of the OV25- and PIB-coated QCMs we fabricated made possible to discriminate roasty from fatty odorants as was evidenced by the odor recognition map representing the frequency shifts of the OV25-coated QCM against the frequency shift of the PIB-coated QCM. In conclusion, we found that the combination of an OV25-coated QCM and a PIB-coated QCM was successful in discriminating roasty odorants from fatty odorants at the ppm level.

  3. Thermal degradation of deoxynivalenol during maize bread baking.

    PubMed

    Numanoglu, E; Gökmen, V; Uygun, U; Koksel, H

    2012-01-01

    The thermal degradation of deoxynivalenol (DON) was determined at isothermal baking conditions within the temperature range of 100-250°C, using a crust-like model, which was prepared with naturally contaminated maize flour. No degradation was observed at 100°C. For the temperatures of 150, 200 and 250°C, thermal degradation rate constants (k) were calculated and temperature dependence of DON degradation was observed by using Arrhenius equation. The degradation of DON obeyed Arrhenius law with a regression coefficient of 0.95. A classical bread baking operation was also performed at 250°C for 70 min and the rate of DON degradation in the bread was estimated by using the kinetic data derived from the model study. The crust and crumb temperatures recorded during bread baking were used to calculate the thermal degradation rate constants (k) and partial DON degradations at certain time intervals. Using these data, total degradation at the end of the entire baking process was predicted for both crust and crumb. This DON degradation was consistent with the experimental degradation data, confirming the accuracy of kinetic constants determined by means of the crust-like model.

  4. Thermal inactivation kinetics of β-galactosidase during bread baking.

    PubMed

    Zhang, Lu; Chen, Xiao Dong; Boom, Remko M; Schutyser, Maarten A I

    2017-06-15

    In this study, β-galactosidase was utilized as a model enzyme to investigate the mechanism of enzyme inactivation during bread baking. Thermal inactivation of β-galactosidase was investigated in a wheat flour/water system at varying temperature-moisture content combinations, and in bread during baking at 175 or 205°C. In the wheat flour/water system, the thermostability of β-galactosidase increased with decreased moisture content, and a kinetic model was accurately fitted to the corresponding inactivation data (R(2)=0.99). Interestingly, the residual enzyme activity in the bread crust (about 30%) was hundredfold higher than that in the crumb (about 0.3%) after baking, despite the higher temperature in the crust throughout baking. This result suggested that the reduced moisture content in the crust increased the thermostability of the enzyme. Subsequently, the kinetic model reasonably predicted the enzyme inactivation in the crumb using the same parameters derived from the wheat flour/water system. However, the model predicted a lower residual enzyme activity in the crust compared with the experimental result, which indicated that the structure of the crust may influence the enzyme inactivation mechanism during baking. The results reported can provide a quantitative understanding of the thermal inactivation kinetics of enzyme during baking, which is essential to better retain enzymatic activity in bakery products supplemented with heat-sensitive enzymes.

  5. Fatty Acid and Proximate Composition of Bee Bread

    PubMed Central

    Kaplan, Muammer; Karaoglu, Öznur; Eroglu, Nazife

    2016-01-01

    Summary Palynological spectrum, proximate and fatty acid (FA) composition of eight bee bread samples of different botanical origins were examined and significant variations were observed. The samples were all identified as monofloral, namely Castanea sativa (94.4%), Trifolium spp. (85.6%), Gossypium hirsutum (66.2%), Citrus spp. (61.4%) and Helianthus annuus (45.4%). Each had moisture content between 11.4 and 15.9%, ash between 1.9 and 2.54%, fat between 5.9 and 11.5%, and protein between 14.8 and 24.3%. A total of 37 FAs were determined with most abundant being (9Z,12Z,15Z)-octadeca-9,12,15-trienoic, (9Z,12Z)- -octadeca-9,12-dienoic, hexadecanoic, (Z)-octadec-9-enoic, (Z)-icos-11-enoic and octadecanoic acids. Among all, cotton bee bread contained the highest level of ω-3 FAs, i.e. 41.3%. Unsaturated to saturated FA ratio ranged between 1.38 and 2.39, indicating that the bee bread can be a good source of unsaturated FAs. PMID:28115909

  6. Psyllium as a substitute for gluten in bread.

    PubMed

    Zandonadi, Renata Puppin; Botelho, Raquel Braz Assunção; Araújo, Wilma Maria Coelho

    2009-10-01

    Celiac disease is an antibody-mediated enteropathy that presents permanent intolerance to ingested gluten. Currently, only one kind of treatment is available: the complete dietary elimination of all sources of gluten. The aim of the present study was to evaluate the effect of replacing gluten with psyllium on sensory characteristics of bread dough and to compare the chemical, nutritional, technological, and sensory characteristics of the modified preparations. This study is experimental and was subdivided into five steps: selection and development of preparation, chemical analysis, sensory analysis, and statistical analysis. Modified samples of the bread dough achieved a 93.0% acceptance rate for individuals with celiac disease and up to 97.0% for individuals without celiac disease. The most affected characteristics were odor and texture. In terms of chemical composition of the bread dough, energy was reduced by 32.1% and the fat fraction was 42.3% before being cooked. Data obtained from sensory analysis of psyllium doughs indicate that the products had good acceptance by individuals with celiac disease as well as by individuals without celiac disease. This suggests that psyllium can replace gluten in preparations. Furthermore, in terms of chemical composition, products made with modified dough had less fat and fewer calories.

  7. Rye flour enriched with arabinoxylans in rye bread making.

    PubMed

    Buksa, Krzysztof; Nowotna, Anna; Ziobro, Rafał; Gambuś, Halina

    2015-01-01

    The aim of the study was to investigate physical and chemical properties of preparations of water soluble arabinoxylans (arabinoxylan-enriched flour) obtained by industrial method and their derivatives (obtained by hydrolysis and cross-linking of aranbinoxylans), as well as their impact on baking properties of rye flours. Additionally, these results were compared with highly purified arabinoxylans prepared by laboratory method and well characterized in the literature. Flour enriched with arabinoxylans was obtained by industrial method involving air separation of flour particles. It was characterized by 8.6% arabinoxylan content, lack of insoluble material and substantial residue (67%) of starch and dextrins. The addition of all industrial method preparations in amount of 10% (i.e. approx. 1% water soluble arabinoxylans), to rye flours resulted in an increase in water absorption, bread volume and decrease in hardness of the bread crumb and the effect was especially strong in the case of flour type 720. Due to the easiness of isolation procedure, industrial method preparation could be advised as an improver for rye bread making.

  8. Fungi with multifunctional lifestyles: endophytic insect pathogenic fungi.

    PubMed

    Barelli, Larissa; Moonjely, Soumya; Behie, Scott W; Bidochka, Michael J

    2016-04-01

    This review examines the symbiotic, evolutionary, proteomic and genetic basis for a group of fungi that occupy a specialized niche as insect pathogens as well as endophytes. We focus primarily on species in the genera Metarhizium and Beauveria, traditionally recognized as insect pathogenic fungi but are also found as plant symbionts. Phylogenetic evidence suggests that these fungi are more closely related to grass endophytes and diverged from that lineage ca. 100 MYA. We explore how the dual life cycles of these fungi as insect pathogens and endophytes are coupled. We discuss the evolution of insect pathogenesis while maintaining an endophytic lifestyle and provide examples of genes that may be involved in the transition toward insect pathogenicity. That is, some genes for insect pathogenesis may have been co-opted from genes involved in endophytic colonization. Other genes may be multifunctional and serve in both lifestyle capacities. We suggest that their evolution as insect pathogens allowed them to effectively barter a specialized nitrogen source (i.e. insects) with host plants for photosynthate. These ubiquitous fungi may play an important role as plant growth promoters and have a potential reservoir of secondary metabolites.

  9. Low bioaccessibility of vitamin D2 from yeast-fortified bread compared to crystalline D2 bread and D3 from fluid milks.

    PubMed

    Lipkie, Tristan E; Ferruzzi, Mario G; Weaver, Connie M

    2016-11-09

    The assessment of the efficacy of dietary and supplemental vitamin D tends to be confounded by differences in the serum 25-hydroxyvitamin D response between vitamin D2 and vitamin D3. Serum response differences from these vitamers may be due to differences in bioavailability. To address this specifically, the bioaccessibility was assessed for vitamin D2 from breads fortified with UV-treated yeast, and a benchmark against staple vitamin D3 fortified foods including bovine milks and infant formula, as well as crystalline vitamin D2 fortified bread. Fortified foods were subjected to a three-stage static in vitro digestion model, and vitamin D was analyzed by HPLC-MS. Vitamin D bioaccessibility was significantly greater from bovine milks and infant formula (71-85%) than from yeast-fortified sandwich breads (6-7%). Bioaccessibility was not different between whole wheat and white wheat bread (p > 0.05), but was ∼4× lower from yeast-fortified bread than from crystalline vitamin D2 fortified bread (p < 0.05). Intact yeast cells were observed in the digesta of yeast fortified bread. These results indicate that the low bioavailability of yeast D2 in comparison to other vitamin D2 sources is likely due to entrapment within a less digestible yeast matrix and not only to metabolic differences between vitamins D2 and D3.

  10. Characterization of aerobic spore-forming bacteria associated with industrial dairy processing environments and product spoilage.

    PubMed

    Lücking, Genia; Stoeckel, Marina; Atamer, Zeynep; Hinrichs, Jörg; Ehling-Schulz, Monika

    2013-09-02

    Due to changes in the design of industrial food processing and increasing international trade, highly thermoresistant spore-forming bacteria are an emerging problem in food production. Minimally processed foods and products with extended shelf life, such as milk products, are at special risk for contamination and subsequent product damages, but information about origin and food quality related properties of highly heat-resistant spore-formers is still limited. Therefore, the aim of this study was to determine the biodiversity, heat resistance, and food quality and safety affecting characteristics of aerobic spore-formers in the dairy sector. Thus, a comprehensive panel of strains (n=467), which originated from dairy processing environments, raw materials and processed foods, was compiled. The set included isolates associated with recent food spoilage cases and product damages as well as isolates not linked to product spoilage. Identification of the isolates by means of Fourier-transform infrared spectroscopy and molecular methods revealed a large biodiversity of spore-formers, especially among the spoilage associated isolates. These could be assigned to 43 species, representing 11 genera, with Bacillus cereus s.l. and Bacillus licheniformis being predominant. A screening for isolates forming thermoresistant spores (TRS, surviving 100°C, 20 min) showed that about one third of the tested spore-formers was heat-resistant, with Bacillus subtilis and Geobacillus stearothermophilus being the prevalent species. Strains producing highly thermoresistant spores (HTRS, surviving 125°C, 30 min) were found among mesophilic as well as among thermophilic species. B. subtilis and Bacillus amyloliquefaciens were dominating the group of mesophilic HTRS, while Bacillus smithii and Geobacillus pallidus were dominating the group of thermophilic HTRS. Analysis of spoilage-related enzymes of the TRS isolates showed that mesophilic strains, belonging to the B. subtilis and B. cereus

  11. Bread formulated with guava powder was enriched in phenolic and aroma compounds, and was highly acceptable by consumers.

    PubMed

    Castelo-Branco, Vanessa N; Lago, Mabel G; Minuzzo, Daniela A; Moura-Nunes, Nathália; Torres, Alexandre G; Nunes, Juliana C; Monteiro, Mariana

    2016-12-01

    Guava powder (GP) was used as source of aroma and phenolic compounds to fortify wheat bread 10% (GB10) and 20% (GB20), substituting for wheat flour. Phenolic compounds, antioxidant capacity, volatile compounds profile, and sensory acceptability of control bread (CB; without GP) and guava breads (GB) were evaluated. Incorporation of GP increased roughly 2-to-3-fold the phenolic compounds contents of bread. Ten phenolic compounds were identified in GB20, and quercetin-3-O-rutinoside was the major compound, while in CB, ferulic acid was the major among the six phenolic compounds in CB. Bread making seemed to promote the release of phenolic compounds from structural components. Breads incorporated with GP presented a richer volatile profile than CB, especially due to the presence of terpenes. GB improved aroma profile of bread. GP added aroma compounds and phenolic antioxidants, and seemed to be an interesting approach to enhance bread bioactivity and acceptability.

  12. Effect of DHA containing oils and powders on baking performance and quality of white pan bread.

    PubMed

    Serna-Saldivar, Sergio O; Zorrilla, Raquel; De La Parra, Columba; Stagnitti, George; Abril, Ruben

    2006-09-01

    Different sources of DHA and/or n-3 (omega-3) rich oils, oil emulsions and microencapsulated (ME) powders were tested at two different concentrations with the aim of producing fortified pan bread. Three oils (S-algae, fish and flax), two emulsified algae oils (Emulsion-P and Emulsion-L) and two ME oils (ME-S algae and ME-C algae) were compared. The DHA and n-3 oils replaced part of the shortening in order to obtain 32 g slices enriched with 25 or 50 mg DHA, 35 or 70 mg total n-3 from fish oil and 90 or 180 mg linolenic from flax oil. Addition of oils did not significantly affect water absorption but reduced mix time whereas addition of the ME oils decreased both water absorption and mix time. Breads enriched with flax or ME-C oils had lower volume and higher density than the control, ME-S algae, Emulsion-P and Emulsion-L breads. All breads lost texture throughout 14 d storage, the major changes occurred after 3 d. The ME-S algae oil bread had the best softness after 14 d storage whereas breads produced from ME-S algae or ME-C algae oils had the poorest texture. Sensory evaluations indicated that the color of the ME-S algae oil fortified bread was significantly less preferred than the other loaves. After 6 d the control bread had higher acceptability compared with the rest of the breads enriched with high levels of DHA or omega-3 oils. The high-enriched fish oil bread was well accepted during the first days of storage but had the least preferred acceptability after 13 d. The best fortified breads were those supplemented with S-algae oil, Emulsion-P and Emulsion-L oils.

  13. Melanized Fungi in Human Disease

    PubMed Central

    Revankar, Sanjay G.; Sutton, Deanna A.

    2010-01-01

    Summary: Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes. Many are soil organisms and are generally distributed worldwide, though certain species appear to have restricted geographic ranges. Though they are uncommon causes of disease, melanized fungi have been increasingly recognized as important pathogens, with most reports occurring in the past 20 years. The spectrum of diseases with which they are associated has also broadened and includes allergic disease, superficial and deep local infections, pneumonia, brain abscess, and disseminated infection. For some infections in immunocompetent individuals, such as allergic fungal sinusitis and brain abscess, they are among the most common etiologic fungi. Melanin is a likely virulence factor for these fungi. Diagnosis relies on careful microscopic and pathological examination, as well as clinical assessment of the patient, as these fungi are often considered contaminants. Therapy varies depending upon the clinical syndrome. Local infection may be cured with excision alone, while systemic disease is often refractory to therapy. Triazoles such as voriconazole, posaconazole, and itraconazole have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and optimal treatment of these uncommon infections. PMID:20930077

  14. Effect of high molecular weight glutenin subunit composition in common wheat on dough properties and steamed bread quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Steamed bread is a popular staple in Asia with different flour quality requirements from pan bread. Little is known about how glutenin characteristics affect steamed bread quality. This work investigated how deletions of high molecular weight glutenin subunits (HMW-GS) influence gluten properties an...

  15. 40 CFR 408.130 - Applicability; description of the breaded shrimp processing in the contiguous States subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... breaded shrimp processing in the contiguous States subcategory. 408.130 Section 408.130 Protection of... SEAFOOD PROCESSING POINT SOURCE CATEGORY Breaded Shrimp Processing in the Contiguous States Subcategory § 408.130 Applicability; description of the breaded shrimp processing in the contiguous...

  16. 40 CFR 408.130 - Applicability; description of the breaded shrimp processing in the contiguous States subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... breaded shrimp processing in the contiguous States subcategory. 408.130 Section 408.130 Protection of... SEAFOOD PROCESSING POINT SOURCE CATEGORY Breaded Shrimp Processing in the Contiguous States Subcategory § 408.130 Applicability; description of the breaded shrimp processing in the contiguous...

  17. 40 CFR 408.130 - Applicability; description of the breaded shrimp processing in the contiguous States subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... breaded shrimp processing in the contiguous States subcategory. 408.130 Section 408.130 Protection of... SEAFOOD PROCESSING POINT SOURCE CATEGORY Breaded Shrimp Processing in the Contiguous States Subcategory § 408.130 Applicability; description of the breaded shrimp processing in the contiguous...

  18. 40 CFR 408.130 - Applicability; description of the breaded shrimp processing in the contiguous States subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... breaded shrimp processing in the contiguous States subcategory. 408.130 Section 408.130 Protection of... SEAFOOD PROCESSING POINT SOURCE CATEGORY Breaded Shrimp Processing in the Contiguous States Subcategory § 408.130 Applicability; description of the breaded shrimp processing in the contiguous...

  19. 40 CFR 408.130 - Applicability; description of the breaded shrimp processing in the contiguous States subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... breaded shrimp processing in the contiguous States subcategory. 408.130 Section 408.130 Protection of... SEAFOOD PROCESSING POINT SOURCE CATEGORY Breaded Shrimp Processing in the Contiguous States Subcategory § 408.130 Applicability; description of the breaded shrimp processing in the contiguous...

  20. Proteome Studies of Filamentous Fungi

    SciTech Connect

    Baker, Scott E.; Panisko, Ellen A.

    2011-04-20

    The continued fast pace of fungal genome sequence generation has enabled proteomic analysis of a wide breadth of organisms that span the breadth of the Kingdom Fungi. There is some phylogenetic bias to the current catalog of fungi with reasonable DNA sequence databases (genomic or EST) that could be analyzed at a global proteomic level. However, the rapid development of next generation sequencing platforms has lowered the cost of genome sequencing such that in the near future, having a genome sequence will no longer be a time or cost bottleneck for downstream proteomic (and transcriptomic) analyses. High throughput, non-gel based proteomics offers a snapshot of proteins present in a given sample at a single point in time. There are a number of different variations on the general method and technologies for identifying peptides in a given sample. We present a method that can serve as a “baseline” for proteomic studies of fungi.

  1. Effect of water content and flour particle size on gluten-free bread quality and digestibility.

    PubMed

    de la Hera, Esther; Rosell, Cristina M; Gomez, Manuel

    2014-05-15

    The impact of dough hydration level and particle size distribution of the rice flour on the gluten free bread quality and in vitro starch hydrolysis was studied. Rice flour was fractionated in fine and coarse parts and mixed with different amounts of water (70%, 90% and 110% hydration levels) and the rest of ingredients used for making gluten free bread. A larger bread specific volume was obtained when coarser fraction and great dough hydration (90-110%) were combined. The crumb texture improved when increasing dough hydration, although that effect was more pronounced when breads were obtained from a fine fraction. The estimated glycaemic index was higher in breads with higher hydration (90-110%). Slowly digestible starch (SDS) and resistant starch (RS) increased in the coarse flour breads. The coarse fraction complemented with a great dough hydration (90-110%) was the most suitable combination for developing rice bread when considering the bread volume and crumb texture. However, the lowest dough hydration limited starch gelatinization and hindered the in vitro starch digestibility.

  2. Durum and soft wheat flours in sourdough and straight-dough bread-making.

    PubMed

    Rinaldi, Massimiliano; Paciulli, Maria; Caligiani, Augusta; Sgarbi, Elisa; Cirlini, Martina; Dall'Asta, Chiara; Chiavaro, Emma

    2015-10-01

    In the present work, the bread-making performance of durum wheat flour under straight-dough and sourdough procedures were compared to those offered by soft wheat flour by means of selected physical properties (colour, texture, water dynamics, crumb grain characteristic, bulk volume) immediately after baking and during a 5-day shelf-life. The use of sourdough process better preserved both crumb grain characteristic and moisture content of the breads during shelf-life, independently of the wheat flour used. The flour seemed to significantly affect the water dynamics in sourdough breads, being the dehydration process of crust and under-crust faster in durum wheat breads. On the other hand, increasing trend of crumb firmness during the shelf-life was slower in durum wheat breads than in those obtained with soft wheat flour. Initial colour parameters of crust and crumb appeared to less change during shelf-life if durum wheat flour was used. Thus, the final quality of breads after baking and along the shelf-life was significantly affected by both the type of flours and the bread-making process. The results reported herein showed that technological performances of durum wheat flour, especially when combined with sourdough processes, could be successfully exploited for the production of innovative products in the bread-making industry.

  3. Implications of non-covalent interactions in zein-starch dough and bread quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Breads made from non-wheat flours are made from thick batters and are lower quality than wheat bread. The development of visco-elastic doughs from non-wheat proteins would allow a wider range of gluten-free products and would improve the quality of such foods. Only recently has the mechanism of zei...

  4. Characterization of lipids and their oxidation products in baked or fried breaded shrimp products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two breaded shrimp products were examined for the changes in cholesterol, phytosterols, and fatty acids that occurred during cooking. The products were analyzed by gas chromatography (GC) in the raw, baked, and fried states after separation into breading and shrimp components. Cholesterol, campest...

  5. Influence of final baking technologies in partially baked frozen gluten-free bread quality.

    PubMed

    Aguilar, Núria; Albanell, Elena; Miñarro, Begoña; Gallardo, Joan; Capellas, Marta

    2015-03-01

    The effect of final baking in convection oven (FBC), microwave oven (FBM), and microwave oven with susceptor packaging material (FBMS) on partially baked (PB) frozen gluten-free bread characteristics was investigated. Specific volume and crust color of loaves were measured at day 0. Bread moisture, water activity, and crumb and crust texture (at 15, 45, and 90 min after baking) were analyzed at day 0 and after 28 d of frozen storage (-18 °C). Volatile compounds from breads baked in convection oven or microwave oven with susceptor packaging material were also evaluated. Bread finally baked in convection oven or in microwave oven with susceptor packaging increased crust browning. Crumb and roll hardness increased with time after final baking (measured at 15, 45, 90 min) and after 28 d of frozen storage. Bread finally baked in microwave oven was the hardest, due to high water losses. At day 0, bread finally baked in convection oven had softer crumb than bread finally baked in microwave oven with susceptor packaging but, after 28 d of frozen storage, there were no differences between them. Moreover, FBC and FBMS rendered gluten-free breads that could not be distinguished in a triangular test and had the same volatile compounds profile. In conclusion, FBMS could be an alternative to FBC.

  6. Effects of uniquely processed cowpea and plantain flours on wheat bread properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of incorporating uniquely processed whole-seed cowpeas or plantain flours at 10 or 20 g/100 g in all-purpose flour on paste viscosity and bread-baking properties in model bread was determined. Flours from plantains processed as follows: unblanched plantains dried at 60 degrees C (PLC), so...

  7. PCB metabolism by ectomycorrhizal fungi

    SciTech Connect

    Donnelly, P.K.; Fletcher, J.S.

    1995-04-01

    Since 1976 the use of polychlorinated biphenyls (PCBs) has been banned in the U.S. Prior to this, commercial mixtures (Aroclors) had been used extensively as an industrial lubricant because of their nonflammable, nonreactive properties. These same properties are responsible for their persistent in the environment where they bind to soil particles and resist biodegradation. Decontamination of PCB-laden soil is expensive with excavation followed by either storage or incineration as the primary means of remediation. The use of microorganisms for PCB bioremediation has been gaining popularity in the past few years. Bacteria and/or fungi isolated from environmental samples have been used to degrade PCBs under laboratory conditions, but in field trials they have not been as effective. The most common explanation for the poor performance of PCB-degrading organisms introduced at contaminated sites is that they do not compete well with the existing populations. Plant-ectomycorrhizal systems may overcome this problem. Introduction and cultivation of a known host plant at a contaminated site has the potential of providing a survival advantage for ectomycorrhizal fungi that normally colonize the roots of the introduced plant. Ectomycorrhizal fungi exist naturally in the soil and normally grow in association with the roots of a host plant in a mutualistic symbiotic relationship. Preliminary in vitro examination of this group of fungi for their ability to enzymatically degrade xenobiotics is very promising. In vivo studies have shown that some of these fungi have the ability to degrade chlorinated, aromatic compounds, such as 2,4-D and atrazine. The aspect of ectomycorrhizal metabolism was investigated further in the current study by determining the ability of 21 different fungi to metabolize 19 different PCB congeners with varying chlorine content and substitution patterns. 13 refs., 1 fig., 2 tabs.

  8. Green tea catechins reduced the glycaemic potential of bread: an in vitro digestibility study.

    PubMed

    Goh, Royston; Gao, Jing; Ananingsih, Victoria K; Ranawana, Viren; Henry, Christiani Jeyakumar; Zhou, Weibiao

    2015-08-01

    Green tea catechins are potent inhibitors of enzymes for carbohydrate digestion. However, the potential of developing low glycaemic index bakery food using green tea extract has not been investigated. Results of this study showed that addition of green tea extract (GTE) at 0.45%, 1%, and 2% concentration levels significantly reduced the glycaemic potential of baked and steamed bread. The average retention levels of catechins in the baked and steamed bread were 75.3-89.5% and 81.4-99.3%, respectively. Bread fortified with 2% GTE showed a significantly lower level of glucose release during the first 90 min of pancreatic digestion as well as a lower content of rapidly digested starch (RDS) content. A significantly negative correlation was found between the catechin retention level and the RDS content of bread. The potential of transforming bread into a low GI food using GTE fortification was proven to be promising.

  9. Physicochemical, sensory properties and starch in vitro digestion of gluten-free breads.

    PubMed

    Carini, Eleonora; Scazzina, Francesca; Curti, Elena; Fattori, Fabio; Mazzeo, Teresa; Vittadini, Elena

    2015-01-01

    The physicochemical (volume, crumb grain and color), sensory and starch in vitro digestion properties were investigated in four gluten-free breads, produced using gluten-free commercial mixes. Different mixes' formulations and processing parameters led to the production of breads with different crumb grain, specific volume, crust and crumb color, which affected product's sensory acceptability. Generally, more heterogeneous and coarser crumb grain and darker color were more appreciated by the judges. Nutritional composition of gluten-free breads differed mainly for starch and lipids contents, due to a wide variety of ingredients used in breads formulations. Starch availability to hydrolytic enzymes in the gluten-free breads was not influenced by variation in ingredients and nutritional composition, but it was related to the physical structure in terms of specific volume. The higher was the specific volume, the higher was the starch-digested fraction.

  10. Properties of bread dough with added fiber polysaccharides and phenolic antioxidants: a review.

    PubMed

    Sivam, Anusooya S; Sun-Waterhouse, Dongxiao; Quek, SiewYoung; Perera, Conrad O

    2010-10-01

    During breadmaking, different ingredients are used to ensure the development of a continuous protein network that is essential for bread quality. Interests in incorporating bioactive ingredients such as dietary fiber (DF) and phenolic antioxidants into popular foods such as bread have grown rapidly, due to the increased consumer health awareness. The added bioactive ingredients may or may not promote the protein cross-links. Appropriate cross-links among wheat proteins, fiber polysaccharides, and phenolic antioxidants could be the most critical factor for bread dough enhanced with DF and phenolic antioxidants. Such cross-links may influence the structure and properties of a bread system during baking. This article presents a brief overview of our current knowledge of the fate of the key components (wheat proteins, fibers, and phenolic antioxidants) and how they might interact during bread dough development and baking.

  11. The contribution of glutenin macropolymer depolymerization to the deterioration of frozen steamed bread dough quality.

    PubMed

    Wang, Pei; Lee, Tung-Ching; Xu, Xueming; Jin, Zhengyu

    2016-11-15

    Depolymerization of glutenin macropolymers (GMP) widely exists in the frozen dough with little effort in elucidating its effects on steamed bread quality. To clarify this, GMP was fractionated from wheat flour and reconstituted to yeast and chemical leavened dough (YLD/CLD). Results showed that with supplementary GMP fraction, depolymerization degree was alleviated in frozen dough. The bread quality loss from freezing was partially counteracted along with better preserved GMP content. Both of dough elasticity and gas retention capability were enhanced in GMP-enriched frozen dough. Gassing power in frozen YLD decreased while remained constant in CLD. Addition of GMP did not affect the gassing power, which allowed interpreting the improved bread qualities from the enhanced dough elasticity and gas retention capability. Based on the improved facts of frozen steamed bread dough quality with additional GMP fractions, this study revealed the pivotal role of GMP depolymerization on the frozen steamed bread dough quality.

  12. Rheological parameters of dough with inulin addition and its effect on bread quality

    NASA Astrophysics Data System (ADS)

    Bojnanska, T.; Tokar, M.; Vollmannova, A.

    2015-04-01

    The rheological properties of enriched flour prepared with an addition of inulin were studied. The addition of inulin caused changes of the rheological parameters of the recorder curve. 10% and more addition significantly extended development time and on the farinogram were two peaks of consistency, what is a non-standard shape. With increasing addition of inulin resistance to deformation grows and dough is difficult to process, over 15% addition make dough short and unsuitable for making bread. Bread volume, the most important parameter, significantly decreased with inulin addition. Our results suggest a level of 5% inulin to produce a functional bread of high sensory acceptance and a level of 10% inulin produce a bread of satisfactory sensory acceptance. Bread with a level over 10% of inulin was unsatisfactory.

  13. Quality characteristics of bread and cookies enriched with debittered Moringa oleifera seed flour.

    PubMed

    Ogunsina, B S; Radha, C; Indrani, D

    2011-03-01

    The effects of replacing wheat flour with 0-15% debittered moringa seed (DBMS) flour on the dough rheology of wheat flour and physical, sensory and chemical properties of bread were studied. Incorporation of an increasing amount of DBMS from 0 to 15% decreased farinograph water absorption, dough stability, amylograph peak viscosity and overall quality of bread. The bread with 10% DBMS had a typical moringa seed taste and was acceptable. Addition of combination of additives improved the dough strength and quality of bread with 10% DBMS flour. Replacement of wheat flour with 10%, 20% and 30% DBMS grits was found to affect cookies quality. Cookies with 20% DBMS grits had the nutty taste of moringa seeds and were acceptable. Bread with 10% DBMS flour and cookies with 20% DBMS grits had more protein, iron and calcium. Incorporating moringa seeds in baked foods may be exploited as a means of boosting nutrition in Africa and Asia where malnutrition is prevalent.

  14. Properties of Bread Dough with Added Fiber Polysaccharides and Phenolic Antioxidants: A Review

    PubMed Central

    Sivam, Anusooya S; Sun-Waterhouse, Dongxiao; Quek, SiewYoung; Perera, Conrad O

    2010-01-01

    During breadmaking, different ingredients are used to ensure the development of a continuous protein network that is essential for bread quality. Interests in incorporating bioactive ingredients such as dietary fiber (DF) and phenolic antioxidants into popular foods such as bread have grown rapidly, due to the increased consumer health awareness. The added bioactive ingredients may or may not promote the protein cross-links. Appropriate cross-links among wheat proteins, fiber polysaccharides, and phenolic antioxidants could be the most critical factor for bread dough enhanced with DF and phenolic antioxidants. Such cross-links may influence the structure and properties of a bread system during baking. This article presents a brief overview of our current knowledge of the fate of the key components (wheat proteins, fibers, and phenolic antioxidants) and how they might interact during bread dough development and baking. PMID:21535512

  15. Postprandial differences in the plasma metabolome of healthy Finnish subjects after intake of a sourdough fermented endosperm rye bread versus white wheat bread

    PubMed Central

    2011-01-01

    Background The mechanism behind the lowered postprandial insulin demand observed after rye bread intake compared to wheat bread is unknown. The aim of this study was to use the metabolomics approach to identify potential metabolites related to amino acid metabolism involved in this mechanism. Methods A sourdough fermented endosperm rye bread (RB) and a standard white wheat bread (WB) as a reference were served in random order to 16 healthy subjects. Test bread portions contained 50 g available carbohydrate. In vitro hydrolysis of starch and protein were performed for both test breads. Blood samples for measuring glucose and insulin concentrations were drawn over 4 h and gastric emptying rate (GER) was measured. Changes in the plasma metabolome were investigated by applying a comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry metabolomics platform (GC×GC-TOF-MS). Results Plasma insulin response to RB was lower than to WB at 30 min (P = 0.004), 45 min (P = 0.002) and 60 min (P < 0.001) after bread intake, and plasma glucose response was significantly higher at time point 90 min after RB than WB intake (P = 0.045). The starch hydrolysis rate was higher for RB than WB, contrary to the in vitro protein digestibility. There were no differences in GER between breads. From 255 metabolites identified by the metabolomics platform, 26 showed significant postprandial relative changes after 30 minutes of bread intake (p and q values < 0.05). Among them, there were changes in essential amino acids (phenylalanine, methionine, tyrosine and glutamic acid), metabolites involved in the tricarboxylic acid cycle (alpha-ketoglutaric, pyruvic acid and citric acid) and several organic acids. Interestingly, the levels of two compounds involved in the tryptophan metabolism (picolinic acid, ribitol) significantly changed depending on the different bread intake. Conclusions A single meal of a low fibre sourdough rye bread producing low postprandial

  16. Biocontrol Activity of Bacillus subtilis Isolated from Agaricus bisporus Mushroom Compost Against Pathogenic Fungi.

    PubMed

    Liu, Can; Sheng, Jiping; Chen, Lin; Zheng, Yanyan; Lee, David Yue Wei; Yang, Yang; Xu, Mingshuang; Shen, Lin

    2015-07-08

    Bacillus subtilis strain B154, isolated from Agaricus bisporus mushroom compost infected by red bread mold, exhibited antagonistic activities against Neurospora sitophila. Antifungal activity against phytopathogenic fungi was also observed. The maximum antifungal activity was reached during the stationary phase. This antifungal activity was stable over a wide pH and temperature range and was not affected by proteases. Assay of antifungal activity in vitro indicated that a purified antifungal substance could strongly inhibit mycelia growth and spore germination of N. sitophila. In addition, treatment with strain B154 in A. bisporus mushroom compost infected with N. sitophila significantly increased the yield of bisporus mushrooms. Ultraviolet scan spectroscopy, tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis, matrix-associated laser desorption ionization time-of-flight mass spectrometry, and electrospray ionization tandem mass spectrometry analyses revealed a molecular weight consistent with 1498.7633 Da. The antifungal compound might belong to a new type of lipopeptide fengycin.

  17. Physicochemical and sensory properties of soy bread made with germinated, steamed, and roasted soy flour.

    PubMed

    Shin, Doo-Jee; Kim, Wook; Kim, Yookyung

    2013-11-01

    For the development of healthful gluten-free soy bread acceptable to consumers, we evaluated the effects of various processing procedures for soy flour on bread quality, in terms of beany flavour and texture. We pretreated soy flour by both non-heating (raw:NS and germinated:GS) and heating (steamed:SS and roasted:RS) methods. In addition, to improve the loaf volume, we added 1% hydroxypropyl-methylcellulose (HPMC) to RS flour. Lipoxygenase activity was retained in the non-heat-treated flours (279 U/g for NS and 255 U/g for GS), but was significantly reduced in the heat-treated flours (106U/g for SS and 69 U/g for RS). Moreover, heat-treated flour had higher isoflavone and ferric reducing antioxidant power than had non-heat-treated flour. However, RS flour had the lowest moisture content and lowest L value. The GS bread had the highest specific loaf volume (3.53 cm(3)/g), followed by NS (2.96 cm(3)/g), RS (2.25c m(3)/g), and SS (1.81 cm(3)/g) bread. GS bread had the lowest hardness (1.53N), followed by NS (1.65 N), RS (2.00 N), and SS (3.75 N) bread. The addition of 1% HPMC to RS increased the loaf volume (2.44 cm(3)/g), but decreased the bread's hardness (1.80N). As to the sensory properties, the bread with heat-treated flour was perceived to have a less beany odour and taste than was the bread with non-heat-treated flour. However, the latter had a better appearance than the former. These results indicated that soy flour pretreatment could enhance the loaf volume and reduce the beany flavour of whole soy bread.

  18. Comparison of Volatiles Profile and Contents of Trichothecenes Group B, Ergosterol, and ATP of Bread Wheat, Durum Wheat, and Triticale Grain Naturally Contaminated by Mycobiota

    PubMed Central

    Buśko, Maciej; Stuper, Kinga; Jeleń, Henryk; Góral, Tomasz; Chmielewski, Jarosław; Tyrakowska, Bożena; Perkowski, Juliusz

    2016-01-01

    In natural conditions cereals can be infested by pathogenic fungi. These can reduce the grain yield and quality by contamination with mycotoxins which are harmful for plants, animals, and humans. To date, performed studies of the compounds profile have allowed for the distinction of individual species of fungi. The aim of this study was to determine the profile of volatile compounds and trichothecenes of group B, ergosterol, adenosine triphosphate content carried out on a representative sample of 16 genotypes of related cereals: triticale, bread wheat, and durum wheat. Based on an analysis of volatile compounds by means of gas chromatography mass spectrometry and with the use of an electronic nose, volatile profiles for cereals were determined. Differentiation is presented at four levels through discriminant analysis, heatmaps, principal component analysis (PCA), and electronic nose maps. The statistical model was built by subsequent incorporation of chemical groups such as trichothecenes (GC/MS), fungal biomass indicators ergosterol (HPLC) and ATP (luminometric) and volatiles. The results of the discriminatory analyses showed that the volatile metabolites most markedly differentiated grain samples, among which were mainly: lilial, trichodiene, p-xylene. Electronic nose analysis made it possible to completely separate all the analyzed cereals based only on 100 ions from the 50–150 m/z range. The research carried out using chemometric analysis indicated significant differences in the volatile metabolites present in the grain of bread wheat, durum wheat and triticale. The end result of the performed analyses was a complete discrimination of the examined cereals based on the metabolites present in their grain. PMID:27597856

  19. Marine Fungi: Their Ecology and Molecular Diversity

    NASA Astrophysics Data System (ADS)

    Richards, Thomas A.; Jones, Meredith D. M.; Leonard, Guy; Bass, David

    2012-01-01

    Fungi appear to be rare in marine environments. There are relatively few marine isolates in culture, and fungal small subunit ribosomal DNA (SSU rDNA) sequences are rarely recovered in marine clone library experiments (i.e., culture-independent sequence surveys of eukaryotic microbial diversity from environmental DNA samples). To explore the diversity of marine fungi, we took a broad selection of SSU rDNA data sets and calculated a summary phylogeny. Bringing these data together identified a diverse collection of marine fungi, including sequences branching close to chytrids (flagellated fungi), filamentous hypha-forming fungi, and multicellular fungi. However, the majority of the sequences branched with ascomycete and basidiomycete yeasts. We discuss evidence for 36 novel marine lineages, the majority and most divergent of which branch with the chytrids. We then investigate what these data mean for the evolutionary history of the Fungi and specifically marine-terrestrial transitions. Finally, we discuss the roles of fungi in marine ecosystems.

  20. Modified-atmosphere packaging of hen table eggs: effects on pathogen and spoilage bacteria.

    PubMed

    Pasquali, F; Manfreda, G; Olivi, P; Rocculi, P; Sirri, F; Meluzzi, A

    2012-12-01

    As part of a more comprehensive research activity on the use of modified-atmosphere packaging for the improvement of quality and functional properties of table eggs, the effects of air, 100% CO(2), and 100% O(2) packaging were also evaluated on the survival of experimentally inoculated pathogen bacteria (Salmonella Enteritidis, Escherichia coli, and Listeria monocytogenes) as well as on spoilage bacteria (total aerobic mesophilic bacteria) on table eggs during 30 d of storage at 4, 25, and 37°C by colony count method. In general, temperatures played a major role, rather than gasses, in influencing the bacterial survival. In particular, the lowest microbial loads were registered at 4°C on E. coli and spoilage bacteria, whereas 37°C was the best storage temperature to avoid the psychrotropic microorganism L. monocytogenes development regardless of the gas used. One hundred percent CO(2) packaging, in association with a low storage temperature (4°C), had a significant positive effect in reducing Salmonella loads. On eggs inoculated with L. monocytogenes and stored at 4°C as well as on eggs containing only spoilage bacteria and stored at 25°C, 100% CO(2) resulted the best gas in comparison with air and O(2). One hundred percent CO(2) packaging showed no negative effect on pathogen survival compared with air. Although further improvements are required to control RH within packaging to limit bacteria growth/survival, in view of the positive effects of CO(2) packaging on quality traits of table eggs, 100% CO(2) packaging might represent a promising innovative technique for the maintenance of egg characteristics during transport, retail, and domestic storage.

  1. Role of Plasmids in Lactobacillus brevis BSO 464 Hop Tolerance and Beer Spoilage

    PubMed Central

    Bergsveinson, Jordyn; Baecker, Nina; Pittet, Vanessa

    2014-01-01

    Specific isolates of lactic acid bacteria (LAB) can grow in the harsh beer environment, thus posing a threat to brew quality and the economic success of breweries worldwide. Plasmid-localized genes, such as horA, horC, and hitA, have been suggested to confer hop tolerance, a trait required for LAB survival in beer. The presence and expression of these genes among LAB, however, do not universally correlate with the ability to grow in beer. Genome sequencing of the virulent beer spoilage organism Lactobacillus brevis BSO 464 revealed the presence of eight plasmids, with plasmids 1, 2, and 3 containing horA, horC, and hitA, respectively. To investigate the roles that these and the other five plasmids play in L. brevis BSO 464 growth in beer, plasmid curing with novobiocin was used to derive 10 plasmid variants. Multiplex PCRs were utilized to determine the presence or absence of each plasmid, and how plasmid loss affected hop tolerance and growth in degassed (noncarbonated) beer was assessed. Loss of three of the eight plasmids was found to affect hop tolerance and growth in beer. Loss of plasmid 2 (horC and 28 other genes) had the most dramatic effect, with loss of plasmid 4 (120 genes) and plasmid 8 (47 genes) having significant, but smaller, impacts. These results support the contention that genes on mobile genetic elements are essential for bacterial growth in beer and that beer spoilage ability is not dependent solely on the three previously described hop tolerance genes or on the chromosome of a beer spoilage LAB isolate. PMID:25501474

  2. Role of plasmids in Lactobacillus brevis BSO 464 hop tolerance and beer spoilage.

    PubMed

    Bergsveinson, Jordyn; Baecker, Nina; Pittet, Vanessa; Ziola, Barry

    2015-02-01

    Specific isolates of lactic acid bacteria (LAB) can grow in the harsh beer environment, thus posing a threat to brew quality and the economic success of breweries worldwide. Plasmid-localized genes, such as horA, horC, and hitA, have been suggested to confer hop tolerance, a trait required for LAB survival in beer. The presence and expression of these genes among LAB, however, do not universally correlate with the ability to grow in beer. Genome sequencing of the virulent beer spoilage organism Lactobacillus brevis BSO 464 revealed the presence of eight plasmids, with plasmids 1, 2, and 3 containing horA, horC, and hitA, respectively. To investigate the roles that these and the other five plasmids play in L. brevis BSO 464 growth in beer, plasmid curing with novobiocin was used to derive 10 plasmid variants. Multiplex PCRs were utilized to determine the presence or absence of each plasmid, and how plasmid loss affected hop tolerance and growth in degassed (noncarbonated) beer was assessed. Loss of three of the eight plasmids was found to affect hop tolerance and growth in beer. Loss of plasmid 2 (horC and 28 other genes) had the most dramatic effect, with loss of plasmid 4 (120 genes) and plasmid 8 (47 genes) having significant, but smaller, impacts. These results support the contention that genes on mobile genetic elements are essential for bacterial growth in beer and that beer spoilage ability is not dependent solely on the three previously described hop tolerance genes or on the chromosome of a beer spoilage LAB isolate.

  3. Functional properties of selected starter cultures for sour maize bread.

    PubMed

    Edema, Mojisola O; Sanni, Abiodun I

    2008-06-01

    This paper focuses on the functional properties of maize sour-dough microflora selected and tested for their use as starter cultures for sour maize bread. Lactic acid bacteria and yeasts isolated from spontaneously fermented maize dough were selected based on dominance during fermentation and presence at the end of fermentation. Functional properties examined included acidification, leavening and production of some antimicrobial compounds in the fermenting matrix. The organisms previously identified as Lactobacillus plantarum, Lb. brevis, Lb. fermentum, Lb. acidophilus, Pediococcus acidilactici, Leuconostoc mesenteroides and Leuconostoc dextranicum and Saccharomyces cerevisiae were used singly and as mixed cultures in the fermentation (fermentation time: 12h at 28+/-2 degrees C) of maize meal (particle size >0.2mm). The pH fell from an initial value of 5.62-3.05 in maize meals fermented with Lb. plantarum; 4.37 in L. dextranicum+S. cerevisiae compared with the value for the control (no starter) of 4.54. Significant differences (P

  4. Indoor fungi: companions and contaminants.

    PubMed

    Nevalainen, A; Täubel, M; Hyvärinen, A

    2015-04-01

    This review discusses the role of fungi and fungal products in indoor environments, especially as agents of human exposure. Fungi are present everywhere, and knowledge for indoor environments is extensive on their occurrence and ecology, concentrations, and determinants. Problems of dampness and mold have dominated the discussion on indoor fungi. However, the role of fungi in human health is still not well understood. In this review, we take a look back to integrate what cultivation-based research has taught us alongside more recent work with cultivation-independent techniques. We attempt to summarize what is known today and to point out where more data is needed for risk assessment associated with indoor fungal exposures. New data have demonstrated qualitative and quantitative richness of fungal material inside and outside buildings. Research on mycotoxins shows that just as microbes are everywhere in our indoor environments, so too are their metabolic products. Assessment of fungal exposures is notoriously challenging due to the numerous factors that contribute to the variation of fungal concentrations in indoor environments. We also may have to acknowledge and incorporate into our understanding the complexity of interactions between multiple biological agents in assessing their effects on human health and well-being.

  5. [Alternative oxidase in industrial fungi].

    PubMed

    Gu, Shuai; Liu, Qiang; He, Hao; Li, Shuang

    2015-01-01

    Filamentous fungi have been used in industrial fermentation extensively. Based on non-phosphorylating electron transport process, alternative respiration pathway (ARP) acts as an energy overflow, which can balance carbon metabolism and electron transport, allow the continuance of tricarboxylic acid cycle without the formation of ATP, and permit the turnover of carbon skeletons. Alternative respiration pathway also plays an important role in the stress response of fungi and the physiological function of conditioned pathogen. Alternative oxidase (AOX) is the terminal oxidase responsible for the activity of alternative respiration pathway, which exists widely in higher plants, parts of fungi and algae. Owing to the property that alternative oxidase (AOX) is sensitive to salicylhydroxamic acid (SHAM) and insensitive to conventional inhibitors of cytochrome respiration, alternative respiration pathway by AOX is also named as cyanide-resistant respiration (CRR). In recent years, the study of the alternative respiration pathway and alternative oxidase has been a hot topic in the area involving cellular respiration metabolism. In this review we summarized the latest research advances about the functions of alternative respiration pathway and alternative oxidase in industrial fungi.

  6. Evolution of entomopathogenicity in fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The recent completions of a comprehensive study on the fungal phylogeny and a new classification reflecting that phylogeny form a new basis to examine questions about the origins and evolutionary implications of such major habits among fungi as the use living arthropods or other invertebrates as the...

  7. Development and application of Geobacillus stearothermophilus growth model for predicting spoilage of evaporated milk.

    PubMed

    Kakagianni, Myrsini; Gougouli, Maria; Koutsoumanis, Konstantinos P

    2016-08-01

    The presence of Geobacillus stearothermophilus spores in evaporated milk constitutes an important quality problem for the milk industry. This study was undertaken to provide an approach in modelling the effect of temperature on G. stearothermophilus ATCC 7953 growth and in predicting spoilage of evaporated milk. The growth of G. stearothermophilus was monitored in tryptone soy broth at isothermal conditions (35-67 °C). The data derived were used to model the effect of temperature on G. stearothermophilus growth with a cardinal type model. The cardinal values of the model for the maximum specific growth rate were Tmin = 33.76 °C, Tmax = 68.14 °C, Topt = 61.82 °C and μopt = 2.068/h. The growth of G. stearothermophilus was assessed in evaporated milk at Topt in order to adjust the model to milk. The efficiency of the model in predicting G. stearothermophilus growth at non-isothermal conditions was evaluated by comparing predictions with observed growth under dynamic conditions and the results showed a good performance of the model. The model was further used to predict the time-to-spoilage (tts) of evaporated milk. The spoilage of this product caused by acid coagulation when the pH approached a level around 5.2, eight generations after G. stearothermophilus reached the maximum population density (Nmax). Based on the above, the tts was predicted from the growth model as the sum of the time required for the microorganism to multiply from the initial to the maximum level ( [Formula: see text] ), plus the time required after the [Formula: see text] to complete eight generations. The observed tts was very close to the predicted one indicating that the model is able to describe satisfactorily the growth of G. stearothermophilus and to provide realistic predictions for evaporated milk spoilage.

  8. The involvement of bacterial quorum sensing in the spoilage of refrigerated Litopenaeus vannamei.

    PubMed

    Zhu, Suqin; Wu, Haohao; Zeng, Mingyong; Liu, Zunying; Wang, Ying

    2015-01-02

    Quorum-sensing signals in refrigerated shrimp (Litopenaeus vannamei) undergoing spoilage were examined using bioreporter assays, thin-layer chromatography and gas chromatography-mass spectrometry, and the results revealed the presence of three types of autoinducers including acetylated homoserine lactones (AHLs) (i.e., N-hexanoyl-homoserine lactone, N-oxohexanoyl-homoserine lactone and N-octanoyl-homoserine lactone), autoinducer-2, and cyclic dipeptides (i.e., cyclo-(L-Pro-L-Leu), cyclo-(L-Leu-L-Leu) and cyclo-(L-Pro-L-Phe)). Autoinducer-2, rather than any AHL, was detected in extracts from pure cultures of the specific spoilage organisms (SSO), i.e., Shewanella putrefaciens (SS01) and Shewanella baltica (SA02). As for the cyclic peptides, only SA02 was determined to produce cyclo-(L-Pro-L-Leu). According to the transcription levels of LuxR (the master quorum-sensing regulator) in the SSO in response to exogenous autoinducers, the SSO could sense AHLs and cyclo-(L-Leu-L-Leu), rather than autoinducer-2, cyclo-(L-Leu-L-Leu) and cyclo-(L-Pro-L-Phe). In accordance with the results of LuxR expression, the production of biofilm matrixes and extracellular proteases in the SSO was regulated by exogenous AHLs and cyclo-(L-Pro-L-Leu), rather than 4,5-dihydroxy-2,3-pentanedione (the autoinducer-2 precursor), cyclo-(L-Leu-L-Leu) and cyclo-(L-Pro-L-Phe). Exogenous N-hexanoyl-homoserine lactone and cyclo-(L-Pro-L-Leu) increased the growth rates and population percentages of the SSO in shrimp samples under refrigerated storage, and interestingly, exogenous 4,5-dihydroxy-2,3-pentanedione also increased the population percentages of the SSO in vivo by inhibiting the growth of the competing bacteria. However, according to the levels of TVB-N and the volatile organic components in the shrimp samples, exogenous 4,5-dihydroxy-2,3-pentanedione did not accelerate the shrimp spoilage process as N-hexanoyl-homoserine lactone and cyclo-(L-Pro-L-Leu) did. In summary, our results suggest that

  9. The spoilage yeast Zygosaccharomyces bailii forms mitotic spores: a screening method for haploidization.

    PubMed

    Rodrigues, Fernando; Ludovico, Paula; Sousa, Maria João; Steensma, H Yde; Côrte-Real, Manuela; Leão, Cecília

    2003-01-01

    Zygosaccharomyces bailii ISA 1307 and the type strain of this spoilage yeast show a diploid DNA content. Together with a rather peculiar life cycle in which mitotic but no meiotic spores appear to be formed, the diploid DNA content explains the observed difficulties in obtaining auxotrophic mutants. Mitotic chromosome loss induced by benomyl and selection on canavanine media resulted in three haploid strains of Z. bailii. This new set of Z. bailii strains allows the easy isolation of recessive mutants and is suitable for further molecular genetic studies.

  10. The influence of different preservation methods on spoilage bacteria populations inoculated in morcilla de Burgos during anaerobic cold storage.

    PubMed

    Diez, Ana M; Jaime, Isabel; Rovira, Jordi

    2009-06-30

    Blood sausage is a widely consumed traditional product that would benefit from an extended shelf life. The two main spoilage bacteria in vacuum-packaged morcilla de Burgos are Weissella viridescens and Leuconostoc mesenteroides. This study examines the way in which three preservation treatments--organic acid salts (OAS), high-pressure processing (HPP) and pasteurization--influence these bacterial populations and their spoilage behaviour. HPP and pasteurization treatments were found to inhibit growth of the inoculated species and delay sensory spoilage of the product. In both treatments, L. mesenteroides was observed to have a longer recovery time; even so, once its growth started, it grew faster than W. viridescens. This longer recovery time might be due to metabolic modification following treatment, which would affect the production of metabolites such as acetic acid and some aldehydes. W. viridescens was the first strain to recover from the two treatments. It preserved its spoilage behaviour and even increased the production of certain compounds such as acetoin or ethanol. The extended product shelf life following HPP and pasteurization treatments might be due to a combination of various factors such as the fall in both microbial populations, as well as the delay in spoilage caused by damage to L. mesenteroides cells, as this strain is the fastest-acting, most intensive spoilage microorganism. It was observed that the addition of organic salts neither diminished nor delayed the growth of the two inoculated species. Nevertheless, the results also indicate that this treatment inhibits the metabolic activity of L. mesenteroides, resulting once again in an extended product shelf life.

  11. Bioactive terpenes from marine-derived fungi.

    PubMed

    Elissawy, Ahmed M; El-Shazly, Mohamed; Ebada, Sherif S; Singab, AbdelNasser B; Proksch, Peter

    2015-04-03

    Marine-derived fungi continue to be a prolific source of secondary metabolites showing diverse bioactivities. Terpenoids from marine-derived fungi exhibit wide structural diversity including numerous compounds with pronounced biological activities. In this review, we survey the last five years' reports on terpenoidal metabolites from marine-derived fungi with particular attention on those showing marked biological activities.

  12. Bioactive Terpenes from Marine-Derived Fungi

    PubMed Central

    Elissawy, Ahmed M.; El-Shazly, Mohamed; Ebada, Sherif S.; Singab, AbdelNasser B.; Proksch, Peter

    2015-01-01

    Marine-derived fungi continue to be a prolific source of secondary metabolites showing diverse bioactivities. Terpenoids from marine-derived fungi exhibit wide structural diversity including numerous compounds with pronounced biological activities. In this review, we survey the last five years’ reports on terpenoidal metabolites from marine-derived fungi with particular attention on those showing marked biological activities. PMID:25854644

  13. An investigation of bread-baking process in a pilot-scale electrical heating oven using computational fluid dynamics.

    PubMed

    Anishaparvin, A; Chhanwal, N; Indrani, D; Raghavarao, K S M S; Anandharamakrishnan, C

    2010-01-01

    A computational fluid dynamics (CFD) model was developed for bread-baking process in a pilot-scale baking oven to find out the effect of hot air distribution and placement of bread on temperature and starch gelatinization index of bread. In this study, product (bread) simulation was carried out with different placements of bread. Simulation results were validated with experimental measurements of bread temperature. This study showed that nonuniform air flow pattern inside the oven cavity leads to uneven temperature distribution. The study with respect to placement of bread showed that baking of bread in upper trays required shorter baking time and gelatinization index compared to those in the bottom tray. The upper tray bread center reached 100 °C at 1200 s, whereas starch gelatinization completed within 900 s, which was the minimum baking index. Moreover, the heat penetration and starch gelatinization were higher along the sides of the bread as compared to the top and bottom portions of the bread.

  14. Inhibitory effect of various breads on DMH-induced aberrant crypt foci and colorectal tumours in rats.

    PubMed

    Qi, Guangying; Zeng, Sien; Takashima, Tiri; Nozoe, Koichiro; Shobayashi, Megumi; Kakugawa, Koji; Murakami, Kaori; Jikihara, Hiroshi; Zhou, Lihua; Shimamoto, Fumio

    2015-01-01

    Bread is rich in dietary fibre and many phytochemical compounds, which may influence chemoprevention of colon cancer. In the present study, we evaluated the effect of three kinds of bread on DMH-induced colorectal tumours in F344 rats. F344 rats were divided into four groups (Steinmetz Three-Grain bread, Steinmetz Country bread, White bread, and MF). All groups were injected with 1,2-dimethylhydrazine (DMH, 20 mg/kg body weight) once a week for 8 consecutive weeks from 5 weeks of age. To investigate the antioxidant effect of bread, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging rate of bread and the serum levels of 8-hydroxy-deoxyguanosine (8-OHdG) in rats were examined. The number of colorectal aberrant crypt foci (ACF) and the incidence of colorectal tumours were studied after 34 weeks of DMH treatment. The Steinmetz Three-Grain and Steinmetz Country bread groups had higher scavenging rates of the DPPH free radical and lower serum levels of 8-OHdG and incidence of ACF, adenomas, and adenocarcinomas of colon than the White bread and MF group. Steinmetz Three-Grain bread and Steinmetz Country bread have various ingredient combinations that may inhibit colorectal cancer progression.

  15. The ZbYME2 gene from the food spoilage yeast Zygosaccharomyces bailii confers not only YME2 functions in Saccharomyces cerevisiae, but also the capacity for catabolism of sorbate and benzoate, two major weak organic acid preservatives.

    PubMed

    Mollapour, M; Piper, P W

    2001-11-01

    A factor influencing resistances of food spoilage microbes to sorbate and benzoate is whether these organisms are able to catalyse the degradation of these preservative compounds. Several fungi metabolize benzoic acid by the beta-ketoadipate pathway, involving the hydroxylation of benzoate to 4-hydroxybenzoate. Saccharomyces cerevisiae is unable to use benzoate as a sole carbon source, apparently through the lack of benzoate-4-hydroxylase activity. However a single gene from the food spoilage yeast Zygosaccharomyces bailii, heterologously expressed in S. cerevisiae cells, can enable growth of the latter on benzoate, sorbate and phenylalanine. Although this ZbYME2 gene is essential for benzoate utilization by Z. bailii, its ZbYme2p product has little homology to other fungal benzoate-4-hydroxylases studied to date, all of which appear to be microsomal cytochrome P450s. Instead, ZbYme2p has strong similarity to the matrix domain of the S. cerevisiae mitochondrial protein Yme2p/Rna12p/Prp12p and, when expressed as a functional fusion to green fluorescent protein in S. cerevisiae growing on benzoate, is largely localized to mitochondria. The phenotypes associated with loss of the native Yme2p from S. cerevisiae, mostly apparent in yme1,yme2 cells, may relate to increased detrimental effects of endogenous oxidative stress. Heterologous expression of ZbYME2 complements these phenotypes, yet it also confers a potential for weak acid preservative catabolism that the native S. cerevisiae Yme2p is unable to provide. Benzoate utilization by S. cerevisiae expressing ZbYME2 requires a functional mitochondrial respiratory chain, but not the native Yme1p and Yme2p of the mitochondrion.

  16. Use of fungal proteases and selected sourdough lactic acid bacteria for making wheat bread with an intermediate content of gluten.

    PubMed

    Rizzello, Carlo Giuseppe; Curiel, José Antonio; Nionelli, Luana; Vincentini, Olimpia; Di Cagno, Raffaella; Silano, Marco; Gobbetti, Marco; Coda, Rossana

    2014-02-01

    This study was aimed at combining the highest degradation of gluten during wheat flour fermentation with good structural and sensory features of the related bread. As estimated by R5-ELISA, the degree of degradation of immune reactive gluten was ca. 28%. Two-dimensional electrophoresis and RP-FPLC analyses showed marked variations of the protein fractions compared to the untreated flour. The comparison was also extended to in vitro effect of the peptic/tryptic-digests towards K562 and T84 cells. The flour with the intermediate content of gluten (ICG) was used for bread making, and compared to whole gluten (WG) bread. The chemical, structural and sensory features of the ICG bread approached those of the bread made with WG flour. The protein digestibility of the ICG bread was higher than that from WG flour. Also the nutritional quality, as estimated by different indexes, was the highest for ICG bread.

  17. Impact of local hydrothermal treatment during bread baking on soluble amylose, firmness, amylopectin retrogradation and water mobility during bread staling.

    PubMed

    Besbes, Emna; Le Bail, Alain; Seetharaman, Koushik

    2016-01-01

    The impact of hydrothermal processing undergone by bread dough during baking on the degree of starch granule disruption, on leaching of soluble amylose, on water mobility, on firmness and on amylopectin retrogradation during staling has been investigated. Two heating rates during baking have been considered (4.67 and 6.31 °C/min) corresponding respectively to baking temperature of 220 and 240 °C. An increase in firmness and in the amount of retrogradated amylopectin accompanied by a decrease in freezable water has been observed during staling. Although a lower heating rate yielded in larger amount of retrogradated amylopectin retrogradation, it resulted in a lower firmness. Additionally, the amount of soluble amylose and the relaxation times of water measured by Nuclear Magnetic Resonance NMR (T20, T21 and T22) decreased during staling. It was demonstrated that the amount of soluble amylose was higher for bread crumb baked at lower heating rate, indicating that an increasing amount of amylose is leached outside the starch granules. This was corresponding to a greater amount of retrograded amylopectin during staling. Moreover, it was found that the degree of gelatinization differs locally in a same bread slice between the top, the centre and the bottom locations in the crumb. This was attributed to the differences in kinetics of heating, the availability of water during baking and the degree of starch granule disruption during baking. Based on first order kinetic model, it was found that staling kinetics were faster for samples baked at higher heating rate.

  18. Extruded Bread Classification on the Basis of Acoustic Emission Signal With Application of Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Świetlicka, Izabela; Muszyński, Siemowit; Marzec, Agata

    2015-04-01

    The presented work covers the problem of developing a method of extruded bread classification with the application of artificial neural networks. Extruded flat graham, corn, and rye breads differening in water activity were used. The breads were subjected to the compression test with simultaneous registration of acoustic signal. The amplitude-time records were analyzed both in time and frequency domains. Acoustic emission signal parameters: single energy, counts, amplitude, and duration acoustic emission were determined for the breads in four water activities: initial (0.362 for rye, 0.377 for corn, and 0.371 for graham bread), 0.432, 0.529, and 0.648. For classification and the clustering process, radial basis function, and self-organizing maps (Kohonen network) were used. Artificial neural networks were examined with respect to their ability to classify or to cluster samples according to the bread type, water activity value, and both of them. The best examination results were achieved by the radial basis function network in classification according to water activity (88%), while the self-organizing maps network yielded 81% during bread type clustering.

  19. Physical and molecular changes during the storage of gluten-free rice and oat bread.

    PubMed

    Hager, Anna-Sophie; Bosmans, Geertrui M; Delcour, Jan A

    2014-06-18

    Gluten-free bread crumb generally firms more rapidly than regular wheat bread crumb. We here combined differential scanning calorimetry (DSC), texture analysis, and time-domain proton nuclear magnetic resonance (TD (1)H NMR) to investigate the mechanisms underlying firming of gluten-free rice and oat bread. The molecular mobility of water and biopolymers in flour/water model systems and changes thereof after heating and subsequent cooling to room temperature were investigated as a basis for underpinning the interpretation of TD (1)H NMR profiles of fresh crumb. The proton distributions of wheat and rice flour/water model systems were comparable, while that of oat flour/water samples showed less resolved peaks and an additional population at higher T2 relaxation times representing lipid protons. No significant crumb moisture loss during storage was observed for the gluten-free bread loaves. Crumb firming was mainly caused by amylopectin retrogradation and water redistribution within bread crumb. DSC, texture, and TD (1)H NMR data correlated well and showed that starch retrogradation and crumb firming are much more pronounced in rice flour bread than in oat flour bread.

  20. Par-baked Bread Technology: Formulation and Process Studies to Improve Quality.

    PubMed

    Almeida, Eveline Lopes; Steel, Caroline Joy; Chang, Yoon Kil

    2016-01-01

    Extending the shelf-life of bakery products has been an important requirement resulting from the mechanization of this industry and the need to increase the distance for the distribution of final products, caused by the increase in production and consumer demand. Technologies based on the interruption of the breadmaking process represent an alternative to overcome product staling and microbiological deterioration. The production of par-baked breads is one of these technologies. It consists of baking the bread in two stages, and due to the possibility of retarding the second stage, it can be said that the bread can always be offered fresh to the consumer. The technology inserts logistics as part of the production process and creates the "hot point" concept, these being the locations where the bread is finalized, such as in the consumers' homes or sales locations. In this work, a review of the papers published on this subject was carried out, and aspects related to both the formulation and the process were considered. This technology still faces a few challenges, such as solving bread quality problems that appear due to process modifications, and these will also be considered. The market for these breads has grown rapidly and the bakery industry searches innovations related to par-baked bread technology.

  1. Variations in Postprandial Blood Glucose Responses and Satiety after Intake of Three Types of Bread

    PubMed Central

    Lunde, Marianne S. H.; Hjellset, Victoria T.; Holmboe-Ottesen, Gerd; Høstmark, Arne T.

    2011-01-01

    Background. The magnitude and duration of postprandial blood glucose (PPG) elevations are important risk factors of diabetes and coronary heart diseases. Aim. To study PPG after ingestion of breads with and without pea fibre and rapeseed oil. Methods. After fasting overnight, 10 Pakistani immigrant women participated in three experiments having a crossover design and involving ingestion of various types of bread: regular coarse bread or fibre enriched-bread with two levels of rapeseed oil, all providing 25 g available carbohydrates (CHO). Blood glucose and satiety were determined before the meal and every 15 min over the next 2 hours. Results. Intake of an amount of pea fibre-enriched bread containing 25 g CHO attenuated, the postprandial peak glucose value, the incremental area under the glucose versus time curve during 15 to 75 min, and the glycemic profile, and increased duration of satiety (P < .05), as compared with intake of regular bread with 25 g carbohydrate. Conclusion. Pea fibre-enriched breads can reduce PPG and prolong satiety. PMID:21773021

  2. Influence of Bifidobacterium bifidum on release of minerals from bread with differing bran content.

    PubMed

    Nalepa, Beata; Siemianowska, Ewa; Skibniewska, Krystyna Anna

    2012-01-01

    Bread is considered an important source of minerals; however, the presence of fiber and phytic acid reduces bioavailability of minerals from cereal products. It is well established that activity of microorganisms in human gut increases the amount of nutrients released during digestion. The aim of this study was to determine the influence of Bifidobacterium bifidum on release of some minerals from bread using an in vitro process of enzymatic digestion. White bread and with addition of 15, 30, or 45% of bran was baked in a bakery by traditional methods, with addition of yeasts and rye leaven, from flour made of wheat, Tonacja variety. Concentrations of calcium, magnesium, manganese, zinc, copper, and iron were determined by atomic absorption spectrometry. Bread was enzymatically digested in vitro without and with the addition of Bifidobacterium bifidum KD6 (inoculum 10(6) CFU/cm(3)) and percentages of minerals released were determined. The concentration of minerals released during enzymatic digestion varied depending upon the element, quantity of bran, and presence of bacteria. Increase in bran content decreased release of elements. Bifidobacterium bifidum KD6 enhanced amounts of magnesium and zinc released from all types of bread, while manganese and copper rose only from white bread with 15% bran addition. Bacteria decreased amounts of calcium and iron released from bread. Data indicate that diets rich in beneficial bacteria (probiotics) but not balanced with minerals might increase mineral deficiency.

  3. Comparison of Antioxidant Properties of Refined and Whole Wheat Flour and Bread.

    PubMed

    Yu, Lilei; Nanguet, Anne-Laure; Beta, Trust

    2013-11-26

    Antioxidant properties of refined and whole wheat flour and their resultant bread were investigated to document the effects of baking. Total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and oxygen radical absorbance capacity (ORAC) were employed to determine the content of ethanol extractable phenolic compounds. HPLC was used to detect the presence of phenolic acids prior to their confirmation using LC-MS/MS. Whole wheat flour showed significantly higher antioxidant activity than refined flour (p < 0.05). There was a significant effect of the bread-making process with the TPC of whole wheat bread (1.50-1.65 mg/g) and white bread (0.79-1.03 mg/g) showing a respective reduction of 28% and 33% of the levels found in whole wheat and refined flour. Similarly, baking decreased DPPH radical scavenging capacity by 32% and 30%. ORAC values, however, indicated that baking increased the antioxidant activities of whole wheat and refined flour by 1.8 and 2.9 times, respectively. HPLC analysis showed an increase of 18% to 35% in ferulic acid after baking to obtain whole and refined wheat bread containing 330.1 and 25.3 µg/g (average), respectively. Whole wheat flour and bread were superior to refined flour and bread in in vitro antioxidant properties.

  4. Improvement of the quality of wheat bread by addition of glycoside hydrolase family 10 xylanases.

    PubMed

    Zheng, Han; Guo, Bing; Chen, Xiu-Lan; Fan, Sou-Jin; Zhang, Yu-Zhong

    2011-04-01

    Although many xylanases are widely used in the baking industry, only one glycoside hydrolase family 10 (GH 10) xylanase has previously been reported to be effective in baking. In this study, we compared the effectiveness of two GH 10 xylanases, psychrophilic XynA from Glaciecola mesophila and mesophilic EX1 from Trichoderma pseudokoningii, in bread making. The optimal dosages needed to improve wheat flour dough and bread quality were 270-U/kg flour for EX1 and 0.9-U/kg flour for XynA. At their optimal dosage, both XynA and EX1 had significant dough-softening ability, resulting in a 50% reduction in Brabender units. XynA was more effective than EX1 in reducing the time to reach maximum consistency. XynA and EX1 showed similar effects in improving the bread volume (~30% increase). EX1 was more effective in reducing the initial crumb firmness. Although both enzymes exhibited similar anti-staling effects on the bread, based on a decrease in the bread firmness, XynA had a greater effect on reducing the firming rate, and EX1 showed an enhanced reduction in the initial firmness. These results show that these two GH 10 xylanases have unique advantages in improving dough and bread quality and indicate their potential in bread making.

  5. The effect of fermentation and addition of vegetable oil on resistant starch formation in wholegrain breads.

    PubMed

    Buddrick, Oliver; Jones, Oliver A H; Hughes, Jeff G; Kong, Ing; Small, Darryl M

    2015-08-01

    Resistant starch has potential health benefits but the factors affecting its formation in bread and baked products are not well studied. Here, the formation of resistant starch in wholemeal bread products was evaluated in relation to the processing conditions including fermentation time, temperature and the inclusion of palm oil as a vitamin source. The effects of each the factor were assessed using a full factorial design. The impact on final starch content of traditional sourdough fermentation of wholemeal rye bread, as well as the bulk fermentation process of wheat and wheat/oat blends of wholemeal bread, was also assessed by enzyme assay. Palm oil content was found to have a significant effect on the formation of resistant starch in all of the breads while fermentation time and temperature had no significant impact. Sourdough fermentation of rye bread was found to have a greater impact on resistant starch formation than bulk fermentation of wheat and wheat blend breads, most likely due the increased organic acid content of the sourdough process.

  6. Gluten-Free Bread: Influence of Sourdough and Compressed Yeast on Proofing and Baking Properties

    PubMed Central

    Cappa, Carola; Lucisano, Mara; Raineri, Andrea; Fongaro, Lorenzo; Foschino, Roberto; Mariotti, Manuela

    2016-01-01

    The use of sourdough is the oldest biotechnological process to leaven baked goods, and it represents a suitable technology to improve traditional bread texture, aroma, and shelf life. A limited number of studies concerning the use of sourdough in gluten-free (GF) breadmaking have been published in comparison to those on traditional bread. The aim of this study was to compare the properties of GF breads obtained by using a previously in-lab developed GF-sourdough (SD), compressed yeast (CY; Saccharomyces cerevisiae) or their mixture (SDCY) as leavening agents; more specifically, it aims to confirm the findings of a previous studies and to further improve (both in terms of recipe and process) the features of the resulting GF breads. Dough pH and rheological properties were measured. Fresh and stored breads were characterized for weight, height, specific volume, crust and crumb color, moisture, water activity, crumb hardness, and porosity. The combination SDCY was effective in improving bread volume and softness when compared to SD only. Furthermore, SD- and SDCY-crumbs exhibited a less crumbly behavior during storage (69 h, 25 °C, 60% of relative humidity) in comparison to CY-breads. This study confirms the positive effect of SD in GF breadmaking, in particular when used in combination with CY. PMID:28231163

  7. Bread supplemented with amaranth (Amaranthus cruentus): effect of phytates on in vitro iron absorption.

    PubMed

    Mario Sanz-Penella, Juan; Laparra, José Moisés; Sanz, Yolanda; Haros, Monika

    2012-03-01

    The objective of the present study was to evaluate the effect of the bread supplemented with whole amaranth flour (0, 20 and 40%) on iron bioavailability using Caco-2 cells model. The phytate and lower myo-inositol phosphates content in in vitro bread digests were measured by high pressure liquid chromatography. The breads made with amaranth showed significant increase of soluble phytates levels (up to 1.20 μmol/g in dry matter for the 40% of substitution) in comparison with controls, which have not detectable values. A negative correlation among phytate and Fe availability was found when increased levels of amaranth.Ferritin concentration was found 2.7- and 2.0-fold higher (P<0.05) in cultures exposed to 20% and 40% of amaranth formulated bread samples, respectively, compared to control bread. The soluble phytate/Fe molar ratio explained the whole amaranth flour-mediated inhibitory effect associated to the limitation of available Fe; however, the use up to 20% of amaranth in bread formulation appears as a promising strategy to improve the nutritional value of bread, as indicated by the ferritin concentrations quantified in cell cultures. Higher proportion of amaranth flour increased Fe concentration although there was not detected any increase in Fe uptake.

  8. The Occurrence of Beer Spoilage Lactic Acid Bacteria in Craft Beer Production.

    PubMed

    Garofalo, Cristiana; Osimani, Andrea; Milanović, Vesna; Taccari, Manuela; Aquilanti, Lucia; Clementi, Francesca

    2015-12-01

    Beer is one of the world's most ancient and widely consumed fermented alcoholic beverages produced with water, malted cereal grains (generally barley and wheat), hops, and yeast. Beer is considered an unfavorable substrate of growth for many microorganisms, however, there are a limited number of bacteria and yeasts, which are capable of growth and may spoil beer especially if it is not pasteurized or sterile-filtered as craft beer. The aim of this research study was to track beer spoilage lactic acid bacteria (LAB) inside a brewery and during the craft beer production process. To that end, indoor air and work surface samples, collected in the brewery under study, together with commercial active dry yeasts, exhausted yeasts, yeast pellet (obtained after mature beer centrifugation), and spoiled beers were analyzed through culture-dependent methods and PCR-DGGE in order to identify the contaminant LAB species and the source of contamination. Lactobacillus brevis was detected in a spoiled beer and in a commercial active dry yeast. Other LAB species and bacteria ascribed to Staphylococcus sp., Enterobaceriaceae, and Acetobacter sp. were found in the brewery. In conclusion, the PCR-DGGE technique coupled with the culture-dependent method was found to be a useful tool for identifying the beer spoilage bacteria and the source of contamination. The analyses carried out on raw materials, by-products, final products, and the brewery were useful for implementing a sanitization plan to be adopted in the production plant.

  9. Characterization of the spoilage lactic acid bacteria in "sliced vacuum-packed cooked ham".

    PubMed

    Kalschne, Daneysa Lahis; Womer, Rute; Mattana, Ademir; Sarmento, Cleonice Mendes Pereira; Colla, Luciane Maria; Colla, Eliane

    2015-03-01

    The lactic acid bacteria are involved with food fermentation and in such cases with food spoilage. Considering the need to reduce the lactic acid bacteria growth in meat products, the aim of this work was to enumerated and investigated the lactic acid bacteria present on sliced vacuum-packed cooked ham stored at 4 °C and 8 °C for 45 days by phenotypic and molecular techniques. The quantification showed that the lactic acid bacteria were present from the first day with mean count of 1.98 log cfu/g for the four batches analyzed. The lactic acid bacteria grew rapidly on the samples, and plate counts around 7.59 log cfu/g and 8.25 log cfu/g were detected after 45 days of storage at 4 °C and 8 °C, respectively; storage temperatures studied showed significant influence on the microorganism in study growth. The predominant lactic acid bacteria associated with the spoilage samples at one day of storage includes Lactobacillus sp., the phenotypic overlap Leuconostoc / Weissella sp. and Enterococcus sp. At 45 days of storage at 4 and 8 °C the mainly specie was Lactobacillus curvatus , following by Lactobacillus sakei and Leuconostoc mesentereoides ; the Enterococcus sp. was not present in the samples.

  10. Biogenic amines in fish: roles in intoxication, spoilage, and nitrosamine formation--a review.

    PubMed

    Al Bulushi, Ismail; Poole, Susan; Deeth, Hilton C; Dykes, Gary A

    2009-04-01

    Biogenic amines are non-volatile amines formed by decarboxylation of amino acids. Although many biogenic amines have been found in fish, only histamine, cadaverine, and putrescine have been found to be significant in fish safety and quality determination. Despite a widely reported association between histamine and scombroid food poisoning, histamine alone appears to be insufficient to cause food toxicity. Putrescine and cadaverine have been suggested to potentiate histamine toxicity. With respect to spoilage on the other hand, only cadaverine has been found to be a useful index of the initial stage of fish decomposition. The relationship between biogenic amines, sensory evaluation, and trimethylamine during spoilage are influenced by bacterial composition and free amino acid content. A mesophilic bacterial count of log 6-7 cfu/g has been found to be associated with 5 mg histamine/100 g fish, the Food and Drug Administration (FDA) maximum allowable histamine level. In vitro studies have shown the involvement of cadaverine and putrescine in the formation of nitrosamines, nitrosopiperidine (NPIP), and nitrosopyrrolidine (NPYR), respectively. In addition, impure salt, high temperature, and low pH enhance nitrosamine formation, whereas pure sodium chloride inhibits their formation. Understanding the relationships between biogenic amines and their involvement in the formation of nitrosamines could explain the mechanism of scombroid poisoning and assure the safety of many fish products.

  11. Emerging preservation techniques for controlling spoilage and pathogenic microorganisms in fruit juices.

    PubMed

    Aneja, Kamal Rai; Dhiman, Romika; Aggarwal, Neeraj Kumar; Aneja, Ashish

    2014-01-01

    Fruit juices are important commodities in the global market providing vast possibilities for new value added products to meet consumer demand for convenience, nutrition, and health. Fruit juices are spoiled primarily due to proliferation of acid tolerant and osmophilic microflora. There is also risk of food borne microbial infections which is associated with the consumption of fruit juices. In order to reduce the incidence of outbreaks, fruit juices are preserved by various techniques. Thermal pasteurization is used commercially by fruit juice industries for the preservation of fruit juices but results in losses of essential nutrients and changes in physicochemical and organoleptic properties. Nonthermal pasteurization methods such as high hydrostatic pressure, pulsed electric field, and ultrasound and irradiations have also been employed in fruit juices to overcome the negative effects of thermal pasteurization. Some of these techniques have already been commercialized. Some are still in research or pilot scale. Apart from these emerging techniques, preservatives from natural sources have also shown considerable promise for use in some food products. In this review article, spoilage, pathogenic microflora, and food borne outbreaks associated with fruit juices of last two decades are given in one section. In other sections various prevention methods to control the growth of spoilage and pathogenic microflora to increase the shelf life of fruit juices are discussed.

  12. Molecular characterization of Shewanella and Aeromonas isolates associated with spoilage of Common carp (Cyprinus carpio).

    PubMed

    Beaz-Hidalgo, Roxana; Agüeria, Daniela; Latif-Eugenín, Fadua; Yeannes, Maria I; Figueras, Maria J

    2015-01-01

    Storage in ice is a common way of preserving commercial fish species but some microorganisms can still contaminate and participate in the spoilage of the product; therefore, identification of potential harmful microbes is important. Thirteen colonies were isolated from common carp (Cyprinus carpio) that had been stored in ice, whose phenotypic identification revealed that they belonged to the genera Aeromonas (n = 5) and Shewanella (n = 8). Molecular genotyping with ERIC-PCR showed clonality only among two of the five Aeromonas isolates and for two groups (n = 3; n = 2) of the eight Shewanella isolates. Sequencing the rpoD gene showed that four Aeromonas isolates belonged to the species Aeromonas salmonicida and one to A. sobria. Of the eight Shewanella, seven isolates cluster with Shewanella putrefaciens and one with Shewanella profunda in the 16S rRNA phylogenetic tree. However, analysis of the gyrB gene showed that these eight isolates could constitute a new species closely related to S. baltica. The Shewanella and A. salmonicida isolates produce off-odours and reduce trimethylamine oxide, indicating that they might contribute to the spoilage of the fish.

  13. American Lobsters (Homarus Americanus) not Surviving During Air Transport: Evaluation of Microbial Spoilage

    PubMed Central

    Tirloni, Erica; Stella, Simone; Gennari, Mario; Colombo, Fabio

    2016-01-01

    Eighteen American lobsters (Homarus americanus), dead during air transport, were analysed in order to evaluate the microbial population of meat, gills and gut: no specific studies have ever been conducted so far on the microbiological quality of American lobsters’ meats in terms of spoilage microbiota. The meat samples showed very limited total viable counts, in almost all the cases below the level of 6 Log CFU/g, while higher loads were found, as expected, in gut and gills, the most probable source of contamination. These data could justify the possibility to commercialise these not-surviving subjects, without quality concerns for the consumers. Most of the isolates resulted to be clustered with type strains of Pseudoalteromonas spp. (43.1%) and Photobacterium spp. (24.1%), and in particular to species related to the natural marine environment. The distribution of the genera showed a marked inhomogeneity among the samples. The majority of the isolates identified resulted to possess proteolytic (69.3%) and lipolytic ability (75.5%), suggesting their potential spoilage ability. The maintanance of good hygienical practices, especially during the production of ready-to-eat lobsters-based products, and a proper storage could limit the possible replication of these microorganisms. PMID:27800442

  14. Characterisation and detection of spoilage mould responsible for black spot in dry-cured fermented sausages.

    PubMed

    Lozano-Ojalvo, Daniel; Rodríguez, Alicia; Cordero, Mirian; Bernáldez, Victoria; Reyes-Prieto, Mariana; Córdoba, Juan J

    2015-02-01

    Moulds responsible for black spot spoilage of dry-cured fermented sausages were characterised. For this purpose, samples were taken from those dry-cured fermented sausages which showed black spot alteration. Most of the mould strains were first tentatively identified as Penicillium spp. due to their morphological characteristics in different culture conditions, with one strain as Cladosporium sp. The Cladosporium strain was the only one which provoked blackening in culture media. This strain was further characterised by sequencing of ITS1-5.8S-ITS2 rRNA and β-tubulin genes. This mould strain was able to reproduce black spot formation in dry-cured fermented sausage 'salchichón' throughout the ripening process. In addition, a specific and sensitive real-time PCR method was also developed to detect Cladosporium oxysporum responsible for the black spot formation in sausages. This method could be of great interest for the meat industry to detect samples contaminated with this mould before spoilage of product avoiding economic losses for this sector.

  15. Mapping microbial ecosystems and spoilage-gene flow in breweries highlights patterns of contamination and resistance

    PubMed Central

    Bokulich, Nicholas A; Bergsveinson, Jordyn; Ziola, Barry; Mills, David A

    2015-01-01

    Distinct microbial ecosystems have evolved to meet the challenges of indoor environments, shaping the microbial communities that interact most with modern human activities. Microbial transmission in food-processing facilities has an enormous impact on the qualities and healthfulness of foods, beneficially or detrimentally interacting with food products. To explore modes of microbial transmission and spoilage-gene frequency in a commercial food-production scenario, we profiled hop-resistance gene frequencies and bacterial and fungal communities in a brewery. We employed a Bayesian approach for predicting routes of contamination, revealing critical control points for microbial management. Physically mapping microbial populations over time illustrates patterns of dispersal and identifies potential contaminant reservoirs within this environment. Habitual exposure to beer is associated with increased abundance of spoilage genes, predicting greater contamination risk. Elucidating the genetic landscapes of indoor environments poses important practical implications for food-production systems and these concepts are translatable to other built environments. DOI: http://dx.doi.org/10.7554/eLife.04634.001 PMID:25756611

  16. Inhibition of quorum sensing, biofilm, and spoilage potential in Shewanella baltica by green tea polyphenols.

    PubMed

    Zhu, Junli; Huang, Xuzheng; Zhang, Fang; Feng, Lifang; Li, Jianrong

    2015-12-01

    We investigated the quorum sensing (QS) system of Shewanella baltica and the anti-QS related activities of green tea polyphenols (TP) against spoilage bacteria in refrigerated large yellow croaker. Autoinducer-2 (AI-2) and the diketopiperazines (DKPs) cyclo-(L-Pro-L-Leu) and cyclo-(L-Pro-L-Phe) were detected in the culture extract of S. baltica XH2, however, no N-acylhomoserine lactones (AHLs) activity was observed. Green TP at sub-inhibitory concentrations interfered with AI-2 and DKPs activities of S. baltica without inhibiting cell growth and promoted degradation of AI-2. The green TP treatment inhibited biofilm development, exopolysaccharide production and swimming motility of S. baltica in a concentration- dependent manner. In addition, green TP decreased extracellular protease activities and trimethylamine production in S. baltica. A transcriptional analysis showed that green TP repressed the luxS and torA genes in S. baltica, which agreed with the observed reductions in QS activity and the spoilage phenotype. Epigallocatechin gallate (EGCG)-enriched in green TP significantly inhibited AI-2 activity of S. baltica. These findings strongly suggest that green TP could be developed as a new QS inhibitor for seafood preservation to enhance shelf life.

  17. Identification of lactic acid bacteria involved in the spoilage of pasteurized "foie gras" products.

    PubMed

    Matamoros, S; André, S; Hue, I; Prévost, H; Pilet, M F

    2010-07-01

    The spoiling microflora of a re-packaged French "foie gras" product was studied. A total of 54 isolates, originating from two different factories, were identified using phenotypical and molecular methods (partial 16S rDNA sequencing). Weissella viridescens was the main species detected in the products from factory 1 (64% of the isolates). These products had a low lactic acid concentration and were considered as non-spoiled. The microflora of factory 2 was dominated mainly by the genus Lactobacillus (95% of the isolates), and the high lactic acid concentration of these products was linked with a strong spoilage. Among the 30 Lactobacillus strains, three species were predominant: Lactobacillus sakei (nine isolates), Lactobacillus coryniformis (eight isolates) and Lactobacillus paraplantarum (five isolates). Challenge tests were performed to confirm the involvement of the Lactobacillus strains in the spoilage of the product. Sterile "foie gras" samples were inoculated with 14 LAB strains from the collection. The most acidifying strains belonged to the species L. sakei, Lactobacillus plantarum and L. paraplantarum. This confirmed the role of the strains from the Lactobacillus genus as the main spoilers of "foie gras" products and will be useful to design new quality protocols and extend the shelf-life of these products.

  18. Spoilage of vacuum-packed beef by the yeast Kazachstania psychrophila.

    PubMed

    Kabisch, Jan; Erl-Höning, Constanze; Wenning, Mareike; Böhnlein, Christina; Gareis, Manfred; Pichner, Rohtraud

    2016-02-01

    A survey of the psychrotolerant yeast microbiota of vacuum-packed beef was conducted between 2010 and 2012. Chilled vacuum-packed beef (n = 50) sampled from 15 different producers was found to have a mean psychrotolerant yeast count of 3.76 log cfu per cm(2). During this assessment, a recently described yeast named Kazachstania psychrophila was shown to be associated with this product. In order to gain basic knowledge about the spoilage potential of K. psychrophila in vacuum-packed beef, challenge studies were performed and the survival of three different K. psychrophila strains was analyzed during storage of artificially contaminated beef. Beef samples were inoculated with the yeasts at a contamination level of 2 log cfu per cm(2). Survival and growth of K. psychrophila strains was monitored on malt extract agar at regular intervals over 84 days. Kazachstania levels rapidly increased about 5 log units within 16 days under chill conditions (4 °C). Gas bubbles were observed after 16 days, while discoloration and production of off-flavors became evident after 42 days in inoculated samples. This study demonstrates for the first time, that the psychrotolerant yeast K. psychrophila is a dominant spoilage microorganism of vacuum-packed beef products stored at low temperatures, causing sensory defects which result in reduced shelf life, and consequently in considerable economic losses.

  19. Characterization of the spoilage lactic acid bacteria in “sliced vacuum-packed cooked ham”

    PubMed Central

    Kalschne, Daneysa Lahis; Womer, Rute; Mattana, Ademir; Sarmento, Cleonice Mendes Pereira; Colla, Luciane Maria; Colla, Eliane

    2015-01-01

    The lactic acid bacteria are involved with food fermentation and in such cases with food spoilage. Considering the need to reduce the lactic acid bacteria growth in meat products, the aim of this work was to enumerated and investigated the lactic acid bacteria present on sliced vacuum-packed cooked ham stored at 4 °C and 8 °C for 45 days by phenotypic and molecular techniques. The quantification showed that the lactic acid bacteria were present from the first day with mean count of 1.98 log cfu/g for the four batches analyzed. The lactic acid bacteria grew rapidly on the samples, and plate counts around 7.59 log cfu/g and 8.25 log cfu/g were detected after 45 days of storage at 4 °C and 8 °C, respectively; storage temperatures studied showed significant influence on the microorganism in study growth. The predominant lactic acid bacteria associated with the spoilage samples at one day of storage includes Lactobacillus sp., the phenotypic overlap Leuconostoc / Weissella sp. and Enterococcus sp. At 45 days of storage at 4 and 8 °C the mainly specie was Lactobacillus curvatus , following by Lactobacillus sakei and Leuconostoc mesentereoides ; the Enterococcus sp. was not present in the samples. PMID:26221105

  20. Spoilage potentials and antimicrobial resistance of Pseudomonas spp. isolated from cheeses.

    PubMed

    Arslan, S; Eyi, A; Özdemir, F

    2011-12-01

    Pseudomonas spp. are aerobic, gram-negative bacteria that are recognized as major food spoilage microorganisms. A total of 32 (22.9%) Pseudomonas spp. from 140 homemade white cheese samples collected from the open-air public bazaar were isolated and characterized. The aim of the present study was to investigate the biochemical characteristics, the production of extracellular enzymes, slime and β-lactamase, and antimicrobial susceptibility of Pseudomonas spp. isolated from cheeses. The identified isolates including Pseudomonas pseudoalcaligenes, Pseudomonas alcaligenes, Pseudomonas aeruginosa, Pseudomonas fluorescens biovar V, and P. pseudoalcaligenes ssp. citrulli were found to produce extracellular enzymes, respectively: protease and lecithinase production (100%), and lipase activity (85.7, 42.9, 100, and 100%, and nonlipolytic, respectively). The isolates did not produce slime and had no detectable β-lactamase activity. The antimicrobial susceptibility of the isolates was tested using the disk diffusion method. Pseudomonas spp. had the highest resistance to penicillin G (100%), then sulphamethoxazole/trimethoprim (28.1%). However, all Pseudomonas spp. isolates were 100% susceptible to ceftazidime, ciprofloxacin, amikacin, gentamicin, and imipenem. Multidrug-resistance patterns were not observed among these isolates. In this study, Pseudomonas spp., exhibiting spoilage features, were isolated mainly from cheeses. Isolation of this organism from processed milk highlights the need to improve the hygienic practices. All of the stages in the milk processing chain during manufacturing have to be under control to achieve the quality and safety of dairy products.

  1. Optimized dispersion of ZnO nanoparticles and antimicrobial activity against foodborne pathogens and spoilage microorganisms

    NASA Astrophysics Data System (ADS)

    Espitia, Paula Judith Perez; Soares, Nilda de Fátima Ferreira; Teófilo, Reinaldo F.; Vitor, Débora M.; Coimbra, Jane Sélia dos Reis; de Andrade, Nélio José; de Sousa, Frederico B.; Sinisterra, Rubén D.; Medeiros, Eber Antonio Alves

    2013-01-01

    Single primary nanoparticles of zinc oxide (nanoZnO) tend to form particle collectives, resulting in loss of antimicrobial activity. This work studied the effects of probe sonication conditions: power, time, and the presence of a dispersing agent (Na4P2O7), on the size of nanoZnO particles. NanoZnO dispersion was optimized by response surface methodology (RSM) and characterized by the zeta potential (ZP) technique. NanoZnO antimicrobial activity was investigated at different concentrations (1, 5, and 10 % w/w) against four foodborne pathogens and four spoilage microorganisms. The presence of the dispersing agent had a significant effect on the size of dispersed nanoZnO. Minimum size after sonication was 238 nm. An optimal dispersion condition was achieved at 200 W for 45 min of sonication in the presence of the dispersing agent. ZP analysis indicated that the ZnO nanoparticle surface charge was altered by the addition of the dispersing agent and changes in pH. At tested concentrations and optimal dispersion, nanoZnO had no antimicrobial activity against Pseudomonas aeruginosa, Lactobacillus plantarum, and Listeria monocytogenes. However, it did have antimicrobial activity against Escherichia coli, Salmonella choleraesuis, Staphylococcus aureus, Saccharomyces cerevisiae, and Aspergillus niger. Based on the exhibited antimicrobial activity of optimized nanoZnO against some foodborne pathogens and spoilage microorganisms, nanoZnO is a promising antimicrobial for food preservation with potential application for incorporation in polymers intended as food-contact surfaces.

  2. Effectiveness of trisodium phosphate treatment against pathogenic and spoilage bacteria on poultry during refrigerated storage.

    PubMed

    del Río, Elena; Alonso-Calleja, Carlos; Capita, Rosa

    2005-04-01

    To determine the efficacy of trisodium phosphate (TSP) against pathogenic and spoilage bacteria on poultry and to assess the influence of the bacterial combination of inoculum on TSP effect, chicken legs were coinoculated with similar concentrations of a pathogenic (Salmonella enterica ser. Enteritidis or Listeria monocytogenes) and a spoilage (Pseudomonas fluorescens or Brochothrix thermosphacta) bacteria. Samples were dipped in TSP (12%, 15 min) or were not treated (control). Microbiological analysis and pH determinations were carried out at 0, 1, 3, and 5 days of storage (3 degrees C). Significant bacterial reductions (marked in gram-negative species) were observed on TSP-treated samples throughout refrigerated storage. Inoculum composition scarcely influenced the TSP effect against gram-positive bacteria. However, greater reductions were observed on gram-negative bacteria (Salmonella Enteritidis and P. fluorescens) when samples were coinoculated with B. thermosphacta and L. monocytogenes, respectively. Values of pH were higher in TSP-treated than in control samples at all sampling times. The combination of bacteria in inocula did not have a significant influence on pH values.

  3. Potassium transport at the plasma membrane of the food spoilage yeast Zygosaccharomyces bailii.

    PubMed

    Demidchik, Vadim; Macpherson, Neil; Davies, Julia M

    2005-01-15

    Zygosaccharomyces bailii is a commercially important spoilage yeast capable of growth at low pH in the presence of weak organic acid preservatives, such as benzoic acid. A patch-clamp electrophysiological analysis of plasma membrane K+ transport revealed a high conductance pathway for low-affinity K+ uptake. In contrast to the equivalent K+ transporter in Saccharomyces cerevisiae, this system remained operative at low extracellular pH and may therefore facilitate K+ uptake in K(+)-rich and acidic beverages. Benzoate inhibited growth, increased intracellular K+ content, yet decreased the magnitude of the K+ uptake conductance; specifically, the hyperpolarization-activated inwardly-rectifying component was reduced. It is proposed that this adaptation helps maintain a hyperpolarized membrane voltage to effect continued ATPase-mediated H+ extrusion and so combat preservative-induced cytosolic acidosis. Again in contrast to S. cerevisiae, the K+ conductance was relatively insensitive to increased extracellular Ca2+. Paradoxically (and unlike S. cerevisiae) increasing extracellular Ca2+ inhibited growth, suggesting a simple expedient to limit spoilage by Z. bailii.

  4. A mixed-species microarray for identification of food spoilage bacilli.

    PubMed

    Caspers, Martien P M; Schuren, Frank H J; van Zuijlen, Andre C M; Brul, Stanley; Montijn, Roy C; Abee, Tjakko; Kort, Remco

    2011-04-01

    Failure of food preservation is frequently caused by thermostable spores of members of the Bacillaceae family, which show a wide spectrum of resistance to cleaning and preservation treatments. We constructed and validated a mixed-species genotyping array for 6 Bacillus species, including Bacillus subtilis, Bacillus licheniformis, Bacillus pumilus, Bacillus sporothermodurans, Bacillus cereus and Bacillus coagulans, and 4 Geobacillus species, including Geobacillus stearothermophilus, Geobacillus thermocatenulatus, Geobacillus toebii and Geobacillus sp., in order to track food spoilage isolates from ingredient to product. The discriminating power of the array was evaluated with sets of 42 reference and 20 test strains. Bacterial isolates contain a within-species-conserved core genome comprising 68-88% of the entire genome and a non-conserved accessory genome comprising 7-22%. The majority of the core genome markers do not hybridise between species, thus they allow for efficient discrimination at the species level. The accessory genome array markers provide high-resolution discrimination at the level of individual isolates from a single species. In conclusion, the reported mixed-species microarray contains discriminating markers that allow rapid and cost-effective typing of Bacillus food spoilage bacteria in a wide variety of food products.

  5. Emerging Preservation Techniques for Controlling Spoilage and Pathogenic Microorganisms in Fruit Juices

    PubMed Central

    Aneja, Kamal Rai; Dhiman, Romika; Aggarwal, Neeraj Kumar; Aneja, Ashish

    2014-01-01

    Fruit juices are important commodities in the global market providing vast possibilities for new value added products to meet consumer demand for convenience, nutrition, and health. Fruit juices are spoiled primarily due to proliferation of acid tolerant and osmophilic microflora. There is also risk of food borne microbial infections which is associated with the consumption of fruit juices. In order to reduce the incidence of outbreaks, fruit juices are preserved by various techniques. Thermal pasteurization is used commercially by fruit juice industries for the preservation of fruit juices but results in losses of essential nutrients and changes in physicochemical and organoleptic properties. Nonthermal pasteurization methods such as high hydrostatic pressure, pulsed electric field, and ultrasound and irradiations have also been employed in fruit juices to overcome the negative effects of thermal pasteurization. Some of these techniques have already been commercialized. Some are still in research or pilot scale. Apart from these emerging techniques, preservatives from natural sources have also shown considerable promise for use in some food products. In this review article, spoilage, pathogenic microflora, and food borne outbreaks associated with fruit juices of last two decades are given in one section. In other sections various prevention methods to control the growth of spoilage and pathogenic microflora to increase the shelf life of fruit juices are discussed. PMID:25332721

  6. Physicochemical Characterization and Sensory Analysis of Yeast-leavened and Sourdough Soy Breads

    PubMed Central

    Yezbick, Gabrielle; Ahn-Jarvis, Jennifer; Schwartz, Steven J.; Vodovotz, Yael

    2013-01-01

    Sourdough fermentation has been shown to have numerous beneficial effects on bread quality, and nutritionally enhance soy-supplemented bread by altering isoflavone chemical forms. Given this, the objective of this study was to compare the loaf quality and shelf life of sourdough and yeast-leavened soy breads by various physical, thermal, and sensorial methods, and to assess the effects of fermentation by various microorganisms on isoflavone profile in dough and breads using high-performance liquid chromatography analysis. Sourdough fermentation yielded a less extensible dough compared to yeast-leavened soy dough (P < 0.001), and resulted in a harder bread crumb (P < 0.05) and lighter crust color (P < 0.001), compared to yeast-leavened soy bread (Y-B). Sensory analysis revealed a significantly higher overall liking of Y-B compared to sourdough soy bread (SD-B) (P < 0.001). Segmentation analysis of the cohort suggests that overall liking and bread consumption frequency may be determinants of Y-B or SD-B preference. SD-B and Y-B exhibited similar shelf-life properties. Despite significantly different enthalpies associated with the melting of amylose-lipid complexes, thermal analysis of the 2 soy breads stored for 10 d (ambient conditions) demonstrated no significant difference in water distribution and starch retrogradation (P < 0.05). Lastly, SD-B was determined to have 32% of total isoflavones occurring in the aglycone form compared to 17% in Y-B. These findings warrant further investigation of sourdough fermentation as a processing technique for quality and nutritional enhancement of soy-based baked goods. PMID:24024975

  7. Detection and identification of xerophilic fungi in Belgian chocolate confectionery factories.

    PubMed

    De Clercq, Nikki; Van Coillie, Els; Van Pamel, Els; De Meulenaer, Bruno; Devlieghere, Frank; Vlaemynck, Geertrui

    2015-04-01

    Chocolate confectionery fillings are generally regarded as microbiologically stable. The stability of these fillings is largely due to the general practice of adding either alcohol or preservatives. Consumer demands are now stimulating producers to move away from adding alcohol or other preservatives to their confectionery fillings and instead to search for innovative formulations. Such changes in composition can influence the shelf life of the product and may lead to spoilage by xerophilic fungi. The aim of this study was to test whether the production environment of Belgian chocolate confectionery factories and common ingredients of chocolate confectioneries could be potential sources of contamination with xerophilic fungal species. In the factory environment, the general and strictly xerophilic fungal spore load was determined using an RCS Air Sampler device in combination with DG18 and MY50G medium, respectively. Four basic ingredients of chocolate confectionery fillings were also examined for fungal spore levels using a direct plating technique. Detected fungi were identified to species level by a combination of morphological characterization and sequence analysis. Results indicated a general fungal spore load in the range of 50-250 colony forming units per cubic meter of air (CFU/m(3) air) and a more strict xerophilic spore load below 50 CFU/m(3) air. These results indicate rather low levels of fungal spores present in the factory environment. The most prevalent fungi in the factory environment were identified as Penicillium spp., particularly Penicillium brevicompactum. Examination of the basic ingredients of confectionery fillings revealed nuts to be the most likely potential source of direct contamination. In nuts, the most prevalent fungal species identified were Eurotium, particularly Eurotium repens.

  8. Industrial application of selected lactic acid bacteria isolated from local semolinas for typical sourdough bread production.

    PubMed

    Corona, Onofrio; Alfonzo, Antonio; Ventimiglia, Giusi; Nasca, Anna; Francesca, Nicola; Martorana, Alessandra; Moschetti, Giancarlo; Settanni, Luca

    2016-10-01

    Four obligate heterofermentative lactic acid bacteria (LAB) strains (Weissella cibaria PON10030 and PON10032 and Leuconostoc citreum PON 10079 and PON10080) were tested as single strain starters, mono-species dual strain starters, and multiple strain starter for the preparation and propagation of sourdoughs for the production of a typical bread at industrial level. The kinetics of pH and TTA during the daily sourdough refreshments indicated a correct acidification process for all trials. The concentration of lactic and acetic acid increased consistently during fermentation. The resulting molar ratios between these two organic acids in the experimental trials were lower than those observed in the control trial. The microbiological investigation showed levels of approximately 10(9) CFU/mL in almost all sourdoughs and the comparison of the genetic polymorphisms of the dominating LAB with those of the pure cultures evidenced the persistence of the added strains over time. The resulting breads were evaluated for several quality parameters. The breads with the greatest height were obtained with the quadruple combination of leuconostocs and weissellas. The highest softness was registered for the breads obtained from fermentations performed by W. cibaria PON10032 alone and in combination. The different inocula influenced also the color, the void fraction, the cell density and the mean cell area of the breads. Different levels of acids, alcohols, aldehydes, esters, hydrocarbons, ketones, terpenes, furans and phenol were emitted by the breads. The sensory tests indicated the breads from the sourdoughs fermented with the seven LAB inocula as sweeter and less acidic than control breads and the breads from the trials with the highest complexity of LAB inoculums were those more appreciated by tasters. A multivariate approach found strong differences among the trials. In particular, control breads and the breads obtained with different starter LAB were quite distant and a more

  9. Proteomics of Plant Pathogenic Fungi

    PubMed Central

    González-Fernández, Raquel; Prats, Elena; Jorrín-Novo, Jesús V.

    2010-01-01

    Plant pathogenic fungi cause important yield losses in crops. In order to develop efficient and environmental friendly crop protection strategies, molecular studies of the fungal biological cycle, virulence factors, and interaction with its host are necessary. For that reason, several approaches have been performed using both classical genetic, cell biology, and biochemistry and the modern, holistic, and high-throughput, omic techniques. This work briefly overviews the tools available for studying Plant Pathogenic Fungi and is amply focused on MS-based Proteomics analysis, based on original papers published up to December 2009. At a methodological level, different steps in a proteomic workflow experiment are discussed. Separate sections are devoted to fungal descriptive (intracellular, subcellular, extracellular) and differential expression proteomics and interactomics. From the work published we can conclude that Proteomics, in combination with other techniques, constitutes a powerful tool for providing important information about pathogenicity and virulence factors, thus opening up new possibilities for crop disease diagnosis and crop protection. PMID:20589070

  10. Bacteria, fungi and protozoa paper

    EPA Pesticide Factsheets

    Bacteria and fungi in source and treated drinking waterThis dataset is associated with the following publication:King , D., S. Pfaller , M. Donohue , S. Vesper , E. Villegas , M. Ware , S. Glassmeyer , M. Vogal, E. Furlong, and D. Kolpin. Microbial pathogens in source and treated waters from drinking water treatment plants in the United States and implications for human health. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier BV, AMSTERDAM, NETHERLANDS, 562: 987–995, (2016).

  11. Otomycosis due to filamentous fungi.

    PubMed

    García-Agudo, Lidia; Aznar-Marín, Pilar; Galán-Sánchez, Fátima; García-Martos, Pedro; Marín-Casanova, Pilar; Rodríguez-Iglesias, Manuel

    2011-10-01

    Otomycosis is common throughout the world but barely studied in Spain. Our objective was to determine the microbiological and epidemiological characteristics of this pathology in Cadiz (Spain) between 2005 and 2010. Samples from patients with suspicion of otomycosis underwent a direct microscopic examination and culture on different media for fungi and bacteria. Mycological cultures were incubated at 30°C for at least seven days. Identification of fungi was based on colonial morphology and microscopic examination of fungal structure. From a total of 2,633 samples, microbial growth was present in 1,375 (52.2%) and fungal isolation in 390 (28.4%). We identified 228 yeasts and 184 filamentous fungi (13.4% of positive cultures and 47.2% of otomycosis), associated with yeasts in 22 cases (5.6%). The most frequent species were Aspergillus flavus (42.4%), A. niger (35.9%), A. fumigatus (12.5%), A. candidus (7.1%), A. terreus (1.6%), and Paecilomyces variotii (0.5%). Infection was predominant in men (54.9%) and patients beyond 55 years old (46.8%). The most common clinical symptoms were itching (98.9%), otalgia (59.3%), and hypoacusis (56.0%). Fall season reported the lowest number of cases (20.1%). Incidence of otomycosis and fungi producing otomycosis vary within the distinct geographical areas. In Cadiz, this infection is endemic due to warm temperatures, high humidity, sea bathing, and wind, which contributes to disseminate the conidia. Despite Aspergillus niger has been reported as the main causative agent, A. flavus is predominant in Cadiz. Although infection is usually detected in warm months, we observed a homogeneous occurrence of otomycosis in almost all the seasons.

  12. Ambrosia fungi in the insect-fungi symbiosis in relation to cork oak decline.

    PubMed

    Henriques, Joana; Inácio, Maria Lurdes; Sousa, Edmundo

    2006-09-01

    Ambrosia fungi live associated with beetles (Scolytidae and Platypodidae) in host trees and act as a food source for the insects. The symbiotic relation is important to the colonizing strategies of host trees by beetles. Ambrosia fungi are dimorphic: they grow as ambrosial form and as mycelium. The fungi are highly specialized, adapted to a specific beetle and to the biotope where they both live. In addition other fungi have been found such as tree pathogenic fungi that may play a role in insects host colonization success. Saprophytic fungi are also present in insects galleries. These may decompose cellulose and/or be antagonistic to other less beneficial fungi. This paper summarizes the importance of ambrosia fungi and the interaction with insects and hosts. The possibility of the transport of pathogenic fungi by Platypus cylindrus to cork oak thus contributing for its decline is discussed.

  13. Effector proteins of rust fungi

    PubMed Central

    Petre, Benjamin; Joly, David L.; Duplessis, Sébastien

    2014-01-01

    Rust fungi include many species that are devastating crop pathogens. To develop resistant plants, a better understanding of rust virulence factors, or effector proteins, is needed. Thus far, only six rust effector proteins have been described: AvrP123, AvrP4, AvrL567, AvrM, RTP1, and PGTAUSPE-10-1. Although some are well established model proteins used to investigate mechanisms of immune receptor activation (avirulence activities) or entry into plant cells, how they work inside host tissues to promote fungal growth remains unknown. The genome sequences of four rust fungi (two Melampsoraceae and two Pucciniaceae) have been analyzed so far. Genome-wide analyses of these species, as well as transcriptomics performed on a broader range of rust fungi, revealed hundreds of small secreted proteins considered as rust candidate secreted effector proteins (CSEPs). The rust community now needs high-throughput approaches (effectoromics) to accelerate effector discovery/characterization and to better understand how they function in planta. However, this task is challenging due to the non-amenability of rust pathosystems (obligate biotrophs infecting crop plants) to traditional molecular genetic approaches mainly due to difficulties in culturing these species in vitro. The use of heterologous approaches should be promoted in the future. PMID:25191335

  14. Dye removal by immobilised fungi.

    PubMed

    Rodríguez Couto, Susana

    2009-01-01

    Dyes are widely used within the food, pharmaceutical, cosmetic, printing, textile and leather industries. This has resulted in the discharge of highly coloured effluents that affect water transparency and gas solubility in water bodies. Furthermore, they pose a problem because of their carcinogenicity and toxicity. Therefore, removal of such dyes before discharging them into natural water streams is essential. For this, appropriate treatment technologies are required. The treatment of recalcitrant and toxic dyes with traditional technologies is not always effective or may not be environmentally friendly. This has impelled the search for alternative technologies such as biodegradation with fungi. In particular, ligninolytic fungi and their non-specific oxidative enzymes have been reported to be responsible for the decolouration of different synthetic dyes. Thus, the use of such fungi is becoming a promising alternative to replace or complement the current technologies for dye removal. Processes using immobilised growing cells seem to be more promising than those with free cells, since the immobilisation allows using the microbial cells repeatedly and continuously. This paper reviews the application of fungal immobilisation to dye removal.

  15. In-package cold plasma inactivation of pathogenic and spoilage bacteria commonly found on raw chicken carcasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aims: The goal of this study was to test the efficacy of in-package DBD-CP treatment to inactivate poultry-associated spoilage (Pseudomonas fluorescens) and pathogenic (Salmonella enterica Typhimurium, Campylobacter jejuni) bacteria. Methods and Results: Liquid cultures of the bacterial isolates we...

  16. 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.

  17. Bacterial ecology of fermented cucumber rising pH spoilage as determined by non-culture based methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fermented cucumber spoilage (FCS) characterized by rising pH and the appearance of manure- and cheeselike aromas is a challenge of significant economical impact for the pickling industry. Previous culture-based studies identified the yeasts Pichia manshurica and Issatchenkia occidentalis, 4 Gram-pos...

  18. Influence of sodium chloride, pH, and lactic acid bacteria on anaerobic lactic acid utilization during fermented cucumber spoilage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cucumbers are preserved commercially by natural fermentations in 5% to 8% sodium chloride (NaCl) brines. Occasionally, fermented cucumbers spoil after the primary fermentation is complete. This spoilage has been characterized by decreases in lactic acid and a rise in brine pH caused by microbial ins...

  19. Factors affecting microbial spoilage and shelf-life of chilled vacuum-packed lamb transported to distant markets: a review.

    PubMed

    Mills, John; Donnison, Andrea; Brightwell, Gale

    2014-09-01

    Vacuum-packaging and stringent control of storage temperatures enable the export of meat to distant markets, supplying a chilled product that can favourably compete with local fresh meats. To save fuel and reduce emissions, the speed of ships travelling to international markets has decreased resulting in requirement for the shelf-life of chilled lamb to be extended beyond the recognised time of 60-70 days. Growth of microorganisms and ability to cause spoilage of vacuum-packed lamb are dependent on many factors, including the type and initial concentration of spoilage bacteria, meat pH, water activity, availability of substrates, oxygen availability and, most importantly, storage time and temperature of the packaged product. This paper reviews the existing knowledge of the spoilage bacteria affecting vacuum-packed lamb, discusses the impact of these bacteria on product quality, shelf-life and spoilage, and concludes that under specified conditions the shelf-life of chilled lamb can be extended to beyond 70 days.

  20. Transcriptomic analysis on the formation of the viable putative non-culturable state of beer-spoilage Lactobacillus acetotolerans

    PubMed Central

    Liu, Junyan; Deng, Yang; Peters, Brian M.; Li, Lin; Li, Bing; Chen, Lequn; Xu, Zhenbo; Shirtliff, Mark E.

    2016-01-01

    Lactic acid bacteria (LAB) are the most common beer-spoilage bacteria regardless of beer type, and thus pose significant problems for the brewery industry. The aim of this study was to investigate the genetic mechanisms involved in the ability of the hard-to-culture beer-spoilage bacterium Lactobacillus acetotolerans to enter into the viable putative non-culturable (VPNC) state. A genome-wide transcriptional analysis of beer-spoilage L. acetotolerans strains BM-LA14526, BM-LA14527, and BM-LA14528 under normal, mid-term and VPNC states were performed using RNA-sequencing (RNA-seq) and further bioinformatics analyses. GO function, COG category, and KEGG pathway enrichment analysis were conducted to investigate functional and related metabolic pathways of the differentially expressed genes. Functional and pathway enrichment analysis indicated that heightened stress response and reduction in genes associated with transport, metabolic process, and enzyme activity might play important roles in the formation of the VPNC state. This is the first transcriptomic analysis on the formation of the VPNC state of beer spoilage L. acetotolerans. PMID:27819317

  1. Effect of flour extraction rate and baking on thiamine and riboflavin content and antioxidant capacity of traditional rye bread.

    PubMed

    Martinez-Villaluenga, C; Michalska, A; Frias, J; Piskula, M K; Vidal-Valverde, C; Zieliński, H

    2009-01-01

    The effect of rye flour extraction rates and baking on thiamine and riboflavin content, and antioxidant capacity of traditional rye bread were studied and compared with white wheat flour. The content of thiamine was higher (10.9%) in rye dough formulated with dark rye flour (F-100%; extraction rate of 100%) than in rye dough formulated with brown rye flour (F-92%; extraction rate of 92%) that was similar to dough made with wheat flour. The riboflavin content in rye dough made from flour F-100% was also higher (16%) than in dough formulated with flour F-92%, and both provided larger riboflavin content than wheat dough. Baking led to reductions in thiamine of 56% for wheat bread and of 20% for both rye breads; however, this process caused only a 10% decrease in riboflavin for wheat bread and a 30% decrease for rye breads. Trolox equivalent antioxidant capacity, peroxyl radical scavenging capacity, DPPH radical scavenging activity, and Folin-Ciocalteu reducing capacity were higher in rye than in wheat dough and bread. Baking process produced slight changes in antioxidant activity, except for Superoxide Dismutase-like activity where a sharp decrease was observed. Our findings showed that rye breads are an important source of B vitamins and rye breads formulated with dark and brown flours showed better antioxidant properties than wheat bread. Therefore, rye breads should be more widely recommended in human nutrition.

  2. Supplementation of hydroxypropyl methylcellulose into yeast leavened all-whole grain barley bread potentiates cholesterol-lowering effect.

    PubMed

    Kim, Hyunsook; Turowski, Maciej; Anderson, W H Kerr; Young, Scott A; Kim, Yookyung; Yokoyama, Wallace

    2011-07-27

    We investigated in Syrian Golden hamsters the biological impact and its underlying mechanism of single whole grain breads supplemented with 2-3% hydroxypropyl methylcellulose (HPMC), a semisynthetic viscous soluble dietary fiber (SDF) as a substitute for gluten. Hamsters were fed high-fat diets supplemented with 48-65% (w/w) differently ground, freeze-dried single grain breads including whole grain wheat, barley, barley supplemented with HPMC, debranned oat, and oat supplemented with HPMC which were compared to a diet containing microcrystalline cellulose (control). All single grain breads significantly lowered plasma LDL-cholesterol concentrations compared to the control. Enrichment with HPMC further lowered plasma and hepatic cholesterol concentrations. Despite the reduced molecular weight of naturally occurring soluble (1--->3),(1--->4)-β-d-glucan (β-glucan) caused by the bread-making process, whole grain barley breads downregulated hepatic expression of CYP7A1 and HMG-CoAR genes that are responsible for bile acid and cholesterol synthesis, suggesting a possible role of bioactive compounds such as short-chain fatty acids and phenolic compounds from barley bread. Barley bread enriched with HPMC downregulated expression of ABCG5 gene. Taken together, it appears that distinctive modulation of synthesis and excretion of hepatic cholesterol and bile acid contributes to the cholesterol-lowering properties of whole grain barley breads and breads enriched with HPMC. These data suggests that alternative whole grain breads supplemented with HPMC may provide consumers with a staple food that can assist in cholesterol management.

  3. Sourdough-leavened bread improves postprandial glucose and insulin plasma levels in subjects with impaired glucose tolerance.

    PubMed

    Maioli, Mario; Pes, Giovanni Mario; Sanna, Manuela; Cherchi, Sara; Dettori, Mariella; Manca, Elena; Farris, Giovanni Antonio

    2008-06-01

    Sourdough bread has been reported to improve glucose metabolism in healthy subjects. In this study postprandial glycaemic and insulinaemic responses were evaluated in subjects with impaired glucose tolerance (IGT) who had a meal containing sourdough bread leavened with lactobacilli, in comparison to a reference meal containing bread leavened with baker yeast. Sixteen IGT subjects (age range 52-75, average BMI 29.9 +/- 4.2 kg/ m2) were randomly given a meal containing sourdough bread (A) and a meal containing the reference bread (B) in two separate occasions at the beginning of the study and after 7 days. Sourdough bread was leavened for 8 h using a starter containing autochthonous Saccharomyces cerevisiae and several bacilli able to produce a significant amount of D-and L-lactic acid, whereas the reference bread was leavened for 2 h with commercial baker yeast containing Saccharomyces cerevisiae. Plasma glucose and insulin levels were measured at time 0, 30, 60, 120, and 180 min. In IGT subjects sourdough bread induced a significantly lower plasma glucose response at 30 minutes (p = 0.048) and a smaller incremental area under curve (AUC) delta 0-30 and delta 0-60 min (p = 0.020 and 0.018 respectively) in comparison to the bread leavened with baker yeast. Plasma insulin response to this type of bread showed lower values at 30 min (p = 0.045) and a smaller AUC delta 0-30 min (p = 0.018). This study shows that in subjects with IGT glycaemic and insulinaemic responses after the consumption of sourdough bread are lower than after the bread leavened with baker yeast. This effect is likely due to the lactic acid produced during dough leavening as well as the reduced availability of simple carbohydrates. Thus, sour-dough bread may potentially be of benefit in subjects with impaired glucose metabolism.

  4. Spoilage Science

    ERIC Educational Resources Information Center

    Science and Children, 2005

    2005-01-01

    Have you ever tucked away a piece of fruit for later and returned to find it past its prime? Or found some leftovers that had outlived their welcome in the refrigerator? Whether it's fresh or processed, all food eventually spoils. Methods such as freezing, canning, and the use of preservatives lengthen the lifespan of foods, and we--and the modern…

  5. Mesophilic and psychrotrophic bacteria from meat and their spoilage potential in vitro and in beef.

    PubMed

    Ercolini, Danilo; Russo, Federica; Nasi, Antonella; Ferranti, Pasquale; Villani, Francesco

    2009-04-01

    Mesophilic and psychrotrophic populations from refrigerated meat were identified in this study, and the spoilage potential of microbial isolates in packaged beef was evaluated by analyzing the release of volatile organic compounds (VOC) by gas chromatography-mass spectrometry (GC/MS). Fifty mesophilic and twenty-nine psychrotrophic isolates were analyzed by random amplified polymorphic DNA-PCR, and representative strains were identified by 16S rRNA gene sequencing. Carnobacterium maltaromaticum and C. divergens were the species most frequently found in both mesophilic and psychrotrophic populations. Acinetobacter baumannii, Buttiauxella spp. and Serratia spp. were identified among the mesophilic isolates, while Pseudomonas spp. were commonly identified among the psychrotrophs. The isolates were further characterized for their growth at different temperatures and their proteolytic activity in vitro on meat proteins extracts at 7 degrees C. Selected proteolytic strains of Serratia proteamaculans, Pseudomonas fragi, and C. maltaromaticum were used to examine their spoilage potential in situ. Single strains of these species and mixtures of these strains were used to contaminate beef chops that were packed and stored at 7 degrees C. At time intervals up to 1 month, viable counts were determined, and VOC were identified by GC/MS. Generally, the VOC concentrations went to increase during the storage of the contaminated meats, and the profiles of the analyzed meat changed dramatically depending on the contaminating microbial species. About 100 volatiles were identified in the different contaminated samples. Among the detected volatiles, some specific molecules were identified only when the meat was contaminated by a specific microbial species. Compounds such as 2-ethyl-1-hexanol, 2-buten-1-ol, 2-hexyl-1-octanol, 2-nonanone, and 2-ethylhexanal were detectable only for C. maltaromaticum, which also produced the highest number of aldehydes, lactones, and sulfur compounds. The

  6. Impact of water extractable arabinoxylan from rye bran on the frozen steamed bread dough quality.

    PubMed

    Wang, Pei; Tao, Han; Jin, Zhengyu; Xu, Xueming

    2016-06-01

    Impact of water extractable arabinoxylan from rye bran on frozen steamed bread dough quality was investigated in terms of the bread characteristics, ice crystallization, yeast activity as well as the gluten molecular weight distribution and glutenin macropolymer content in the present study. Results showed that water extractable arabinoxylan significantly improved bread characteristics during the 60-day frozen storage. Less water was crystallized in the water extractable arabinoxylan dough during storage, which could explain the alleviated yeast activity loss. For all the frozen dough samples, more soluble high molecular weight (Mw ≈ 91,000-688,000) and low molecular weight (Mw ≈ 91,000-16,000) proteins were derived from glutenin macropolymer depolymerization. Nevertheless, water extractable arabinoxylan dough developed higher glutenin macropolymer content with lowered level of soluble low molecular weight proteins throughout the storage. This study suggested water extractable arabinoxylan from rye bran had great potential to be served as an effective frozen steamed bread dough improver.

  7. Shelf life assessment of industrial durum wheat bread as a function of packaging system.

    PubMed

    Licciardello, Fabio; Giannone, Virgilio; Del Nobile, Matteo Alessandro; Muratore, Giuseppe; Summo, Carmine; Giarnetti, Mariagrazia; Caponio, Francesco; Paradiso, Vito Michele; Pasqualone, Antonella

    2017-06-01

    This study compared the effect of different packaging systems on industrial durum wheat bread shelf-life, with regard to thermoformed packaging (TF) and flow-packaging (FP). Two TFs having different thickness and one FP were compared by assessing physico-chemical and sensorial properties and volatile compounds of sliced bread during 90days of storage. Texture, aw and bread moisture varied according to a first-order kinetic model, with FP samples ageing faster than TFs. Sensorial features such as consistency, stale odor, and sour odor, increased their intensity during storage. Furans decreased, whereas hexanal increased. The Principal Component Analysis of the whole dataset pointed out that the TF system at reduced thickness could be adopted up to 60days, without compromising the standard commercial life of industrial bread and allowing to save packaging material. The FP system would allow further saving, but it should be preferred when the expected product turnover is within 30days.

  8. Monitoring of bread cooling by statistical analysis of laser speckle patterns

    NASA Astrophysics Data System (ADS)

    Lyubenova, Tanya; Stoykova, Elena; Nacheva, Elena; Ivanov, Branimir; Panchev, Ivan; Sainov, Ventseslav

    2013-03-01

    The phenomenon of laser speckle can be used for detection and visualization of physical or biological activity in various objects (e.g. fruits, seeds, coatings) through statistical description of speckle dynamics. The paper presents the results of non-destructive monitoring of bread cooling by co-occurrence matrix and temporal structure function analysis of speckle patterns which have been recorded continuously within a few days. In total, 72960 and 39680 images were recorded and processed for two similar bread samples respectively. The experiments proved the expected steep decrease of activity related to the processes in the bread samples during the first several hours and revealed its oscillating character within the next few days. Characterization of activity over the bread sample surface was also obtained.

  9. Effect of baking on reduction of free and hidden fumonisins in gluten-free bread.

    PubMed

    Bryła, Marcin; Roszko, Marek; Szymczyk, Krystyna; Jędrzejczak, Renata; Słowik, Elżbieta; Obiedziński, Mieczysław W

    2014-10-22

    The aim of the present work was to assess the influence of the baking process on the fumonisin content in gluten-free bread. The dough was made using two methods: without sourdough and with sourdough. Fumonisins were determined using high-performance liquid chromatography with ion-trap mass spectrometry. This study showed that the bread baking process caused a statistically significant drop in the mean concentration of free fumonisins: the reduction levels were 30 and 32% for the direct and sourdough-based methods, respectively. The lower reduction after baking was observed for hidden fumonisins: 19 and 10%, respectively. The presence of some compounds (such as proteins or starch) capable of stabilizing fumonisins during the baking process might be responsible for the observed increase in the hidden-to-free ratio from an initial 0.72 in flour to 0.83 in bread made from sourdough and to 0.95 in sourdough-free bread.

  10. Gluten-free bread formulated with Prosopis ruscifolia (vinal) seed and corn flours.

    PubMed

    Bernardi, C; Sánchez, H; Freyre, M; Osella, C

    2010-05-01

    Vinal (Prosopis ruscifolia) is a wild leguminous tree found widely in the north of Argentina. Like other Prosopis, vinal can grow under extreme temperatures, in poor soils and can tolerate high saline conditions. Taking into account the high protein and gums contents of vinal seeds, a gluten-free bread was developed including them and corn flour. A central composite design involving vinal seed flour/corn starch ratio (X1) and corn flour/corn starch ratio (X2) was used, and second-order models for specific volume (Y1) and bread score (Y2), evaluated by an expert panel, were employed to generate response surfaces. In the optimum zone of response surfaces, a product with higher protein content (5.2 g/100 g) than gluten-free breads found in local commercial markets was obtained. Also, an interesting antioxidant activity (115 mg ascorbic acid equivalent/100 g) was found in optimized gluten-free bread.

  11. A lipase based approach for studying the role of wheat lipids in bread making.

    PubMed

    Gerits, Lien R; Pareyt, Bram; Delcour, Jan A

    2014-08-01

    While endogenous wheat lipids exert a major effect on bread quality, little is known on the way they impact on bread loaf volume (LV). Here we altered wheat flour lipid composition during bread making using lipases in situ. Lipopan F, Lecitase Ultra, and surfactants increased LV to similar extents. The increases in bread LV as a result of these enzymes were related to decreased levels of galactolipids and phospholipids and concomitant increased 'lyso'-lipid as well as free fatty acid (FFA) levels. The FFA formed were transferred to the free lipid fraction, while the 'lyso'-lipids remained in the bound lipid fraction. For optimal gas cell stabilisation, an equilibrium between the lipid classes present and hence, the type of mesophase formed, is essential. Sufficient levels of lipids forming lamellar mesophases and lipids forming hexagonal I mesophases, which respectively form condensed monolayers or emulsify (deleterious) non-polar lipids in dough liquor, are needed.

  12. Effects of germination on the nutritive value and bioactive compounds of brown rice breads.

    PubMed

    Cornejo, Fabiola; Caceres, Patricio J; Martínez-Villaluenga, Cristina; Rosell, Cristina M; Frias, Juana

    2015-04-15

    The effect of germination conditions on the nutritional benefits of germinated brown rice flour (GBR) bread has been determined. The proximate composition, phytic acid, in vitro protein digestibility and in vitro enzymatic hydrolysis of starch, glucose and starch content, as well as the most relevant bioactive compounds (GABA, γ-oryzanol and total phenolic compounds) and antioxidant activity of breads prepared with GBR at different germination conditions was determined. When comparing different germination times (0 h, 12 h, 24 h and 48 h), germination for 48 h provides GBR bread with nutritionally superior quality on the basis of its higher content of protein, lipids and bioactive compounds (GABA and polyphenols), increased antioxidant activity and reduced phytic acid content and glycaemic index, although a slight decrease in in vitro protein digestibility was detected. Overall, germination seems to be a natural and sustainable way to improving the nutritional quality of gluten-free rice breads.

  13. Baking loss of bread with special emphasis on increasing water holding capacity.

    PubMed

    Kotoki, D; Deka, S C

    2010-01-01

    Potato flour (PF), hydroxypropyl methylcellulose (HPMC) and honey were used as baking agents and their effects on baking loss and sensory quality were studied. PF at 1, 2 and 4% levels decreased baking loss followed by HPMC and honey. Water absorption was substantially high with the HPMC (70.8-80.8%) and PF (61.7-71.7%) compared to honey and normal standard bread. PF incorporation increased shelf-life (6-7 days) as compared to HPMC and honey. HPMC incorporated bread had higher moisture content (36.8-38.0%) followed by PF (34.5-35.8%) and honey (34.7%). The ash content was in the order of PF (1%) > honey (4%) > PF (2%) > normal bread > HPMC (0.5 g) > PF (4%) > HPMC (1 g) > HPMC (1.5 g). PF incorporated bread had sensorily highest acceptance followed by HPMC and honey.

  14. Bread dough rheology: Computing with a damage function model

    NASA Astrophysics Data System (ADS)

    Tanner, Roger I.; Qi, Fuzhong; Dai, Shaocong

    2015-01-01

    We describe an improved damage function model for bread dough rheology. The model has relatively few parameters, all of which can easily be found from simple experiments. Small deformations in the linear region are described by a gel-like power-law memory function. A set of large non-reversing deformations - stress relaxation after a step of shear, steady shearing and elongation beginning from rest, and biaxial stretching, is used to test the model. With the introduction of a revised strain measure which includes a Mooney-Rivlin term, all of these motions can be well described by the damage function described in previous papers. For reversing step strains, larger amplitude oscillatory shearing and recoil reasonable predictions have been found. The numerical methods used are discussed and we give some examples.

  15. Structural and functional partitioning of bread wheat chromosome 3B.

    PubMed

    Choulet, Frédéric; Alberti, Adriana; Theil, Sébastien; Glover, Natasha; Barbe, Valérie; Daron, Josquin; Pingault, Lise; Sourdille, Pierre; Couloux, Arnaud; Paux, Etienne; Leroy, Philippe; Mangenot, Sophie; Guilhot, Nicolas; Le Gouis, Jacques; Balfourier, Francois; Alaux, Michael; Jamilloux, Véronique; Poulain, Julie; Durand, Céline; Bellec, Arnaud; Gaspin, Christine; Safar, Jan; Dolezel, Jaroslav; Rogers, Jane; Vandepoele, Klaas; Aury, Jean-Marc; Mayer, Klaus; Berges, Hélène; Quesneville, Hadi; Wincker, Patrick; Feuillet, Catherine

    2014-07-18

    We produced a reference sequence of the 1-gigabase chromosome 3B of hexaploid bread wheat. By sequencing 8452 bacterial artificial chromosomes in pools, we assembled a sequence of 774 megabases carrying 5326 protein-coding genes, 1938 pseudogenes, and 85% of transposable elements. The distribution of structural and functional features along the chromosome revealed partitioning correlated with meiotic recombination. Comparative analyses indicated high wheat-specific inter- and intrachromosomal gene duplication activities that are potential sources of variability for adaption. In addition to providing a better understanding of the organization, function, and evolution of a large and polyploid genome, the availability of a high-quality sequence anchored to genetic maps will accelerate the identification of genes underlying important agronomic traits.

  16. Characteristic coloring curve for white bread during baking.

    PubMed

    Onishi, Masanobu; Inoue, Michiko; Araki, Tetsuya; Iwabuchi, Hisakatsu; Sagara, Yasuyuki

    2011-01-01

    The effect of heating conditions on the crust color formation was investigated during the baking of white bread. The surface temperatures were monitored with thermocouples attached to the inside surface of the loaf pan cover. The trace of the surface color in the L(*)a(*)b(*) color coordinate system is defined as the characteristic coloring curve. The overall baking process was classified into the following four stages based on the characteristic coloring curve: i) pre-heating (surface temperature < 110 °C), ii) Maillard reaction (110-150 °C), iii) caramelization (150-200 °C), and iv) over-baking (surface temperature>200 °C). A linear relationship was observed between the L(*) decrease and the increase in weight loss of a sample at each oven air temperature. The L(*) value appeared to be suitable as an indicator to control the surface color by baking conditions.

  17. Effect of Partial Replacement of Wheat Flour with High Quality Cassava Flour on the Chemical Composition, Antioxidant Activity, Sensory Quality, and Microbial Quality of Bread

    PubMed Central

    Eleazu, Chinedum; Eleazu, Kate; Aniedu, Chinyere; Amajor, John; Ikpeama, Ahamefula; Ebenzer, Ike

    2014-01-01

    In the current study, wheat flour was mixed with high quality cassava flour (HQCF) in several ratios: 90:10, 80:20, 70:30, and 60:40, and used to prepare 10%, 20%, 30%, and 40% National Root Crops Research Institute (NRCRI) cassava bread, respectively. 100% wheat bread was prepared as a control (100% wheat bread). Five bread samples were prepared per group. Antioxidant assays [i.e., 2,2-diphenyl- 1-picrylhydrazyl radical (DPPH) scavenging assay, reducing power assay] revealed that the bread samples had considerable antioxidant capacities. Substitution of wheat flour with HQCF at various concentrations resulted in dose dependent decreases in the mineral and protein contents of the resulting bread samples. The crude fiber content of the bread samples was minimal, while the carbohydrate content of the bread samples ranged from 43.86% to 48.64%. A 20% substitution of wheat flour with HQCF yielded bread samples with a general acceptability that was comparable to that of 100% wheat bread. The mean bacteria counts of the bread samples ranged from 2.0×103 CFU/mL to 1.4×104 CFU/mL, while the fungal counts ranged from 0 CFU/mL to 3×103 CFU/mL. There was a positive correlation between the DPPH antioxidant activities and the reducing powers of the bread samples (R2=0.871) and a positive correlation between the DPPH antioxidant activities and the flavonoid contents of the bread samples (R2=0.487). The higher microbial load of the NRCRI cassava bread samples indicates that these bread samples may have a shorter shelf life than the 100% wheat bread. The significant positive correlation between total flavonoid content and reducing power (R2=0.750) suggests that the flavonoids present in the lipophilic fractions of the bread samples could be responsible for the reductive capacities of the bread samples. PMID:25054110

  18. Effect of bread gluten content on gastrointestinal function: a crossover MRI study on healthy humans.

    PubMed

    Coletta, Marina; Gates, Fred K; Marciani, Luca; Shiwani, Henna; Major, Giles; Hoad, Caroline L; Chaddock, Gemma; Gowland, Penny A; Spiller, Robin C

    2016-01-14

    Gluten is a crucial functional component of bread, but the effect of increasing gluten content on gastrointestinal (GI) function remains uncertain. Our aim was to investigate the effect of increasing gluten content on GI function and symptoms in healthy participants using the unique capabilities of MRI. A total of twelve healthy participants completed this randomised, mechanistic, open-label, three-way crossover study. On days 1 and 2 they consumed either gluten-free bread (GFB), or normal gluten content bread (NGCB) or added gluten content bread (AGCB). The same bread was consumed on day 3, and MRI scans were performed every 60 min from fasting baseline up to 360 min after eating. The appearance of the gastric chime in the images was assessed using a visual heterogeneity score. Gastric volumes, the small bowel water content (SBWC), colonic volumes and colonic gas content and GI symptoms were measured. Fasting transverse colonic volume after the 2-d preload was significantly higher after GFB compared with NGCB and AGCB with a dose-dependent response (289 (SEM 96) v. 212 (SEM 74) v. 179 (SEM 87) ml, respectively; P=0·02). The intragastric chyme heterogeneity score was higher for the bread with increased gluten (AGCB 6 (interquartile range (IQR) 0·5) compared with GFB 3 (IQR 0·5); P=0·003). However, gastric half-emptying time was not different between breads nor were study day GI symptoms, postprandial SBWC, colonic volume and gas content. This MRI study showed novel mechanistic insights in the GI responses to different breads, which are poorly understood notwithstanding the importance of this staple food.

  19. Dough performance, quality and shelf life of flat bread supplemented with fractions of germinated date seed.

    PubMed

    Hejri-Zarifi, Sudiyeh; Ahmadian-Kouchaksaraei, Zahra; Pourfarzad, Amir; Khodaparast, Mohammad Hossein Haddad

    2014-12-01

    Germinated palm date seeds were milled into two fractions: germ and residue. Dough rheological characteristics, baking (specific volume and sensory evaluation), and textural properties (at first day and during storage for 5 days) were determined in Barbari flat bread. Germ and residue fractions were incorporated at various levels ranged in 0.5-3 g/100 g of wheat flour. Water absorption, arrival time and gelatination temperature were decreased by germ fraction but accompanied by an increasing effect on the mixing tolerance index and degree of softening in most levels. Although improvement in dough stability was monitored but specific volume of bread was not affected by both fractions. Texture analysis of bread samples during 5 days of storage indicated that both fractions of germinated date seeds were able to diminish bread staling. Avrami non-linear regression equation was chosen as useful mathematical model to properly study bread hardening kinetics. In addition, principal component analysis (PCA) allowed discriminating among dough and bread specialties. Partial least squares regression (PLSR) models were applied to determine the relationships between sensory and instrumental data.

  20. Effects of waxy wheat flour and water on frozen dough and bread properties.

    PubMed

    Yi, Jinhee; Kerr, William L; Johnson, Jerry W

    2009-06-01

    The quality of bread made from frozen dough is diminished by changes that occur during freezing. New cultivars of waxy wheat flour (WWF), containing less than 2% amylose, offer unique properties for the production of baked products. In this study, dough properties and bread quality were investigated at various levels of WWF (0% to 45% flour weight) and water (55% to 65%). Dough stickiness increased with higher levels of WWF and water. During frozen storage, dough with greater WWF and lower water had less change in stickiness. Maximum resistance to extension (MRE) decreased with higher WWF and water. Dough with greater WWF and less water had less change in extensibility after frozen storage. Dough with greater WWF and water was more extensible. Nuclear magnetic resonance (NMR) studies showed that frozen dough with higher WWF content had lower transverse relaxation (T(2)) time of 9 to 11ms. After frozen storage, dough with higher WWF still showed lower T(2). Dough with 15% WWF had higher yeast activity. Bread made from 15% and 30% WWF had higher volume in bread made from unfrozen and frozen dough. Bread firmness decreased with higher amounts of WWF and water. This research demonstrated that specific combinations of WWF and water produced a better quality of frozen dough and bread.

  1. Preparation and characterization of a laboratory scale selenomethionine-enriched bread. Selenium bioaccessibility.

    PubMed

    Sánchez-Martínez, María; Pérez-Corona, Teresa; Caímara, Carmen; Madrid, Yolanda

    2015-01-14

    This study focuses on the preparation at lab scale of selenomethionine-enriched white and wholemeal bread. Selenium was supplemented either by adding selenite directly to the dough or by using lab-made selenium-enriched yeast. The best results were obtained when using fresh selenium-enriched yeast. The optimum incubation time for selenomethionine-enriched yeast preparation, while keeping formation of selenium byproducts to a minimum, was 96 h. Selenium content measured by isotope dilution analysis (IDA)-ICP-MS in Se-white and Se-wholemeal bread was 1.28 ± 0.02 μg g–1 and 1.16 ± 0.02 μg g–1 (expressed as mean ± SE, 3 replicates), respectively. HPLC postcolumn IDA-ICP-MS measurements revealed that selenomethionine was the main Se species found in Se-enriched bread, which accounted for ca. 80% of total selenium. In vitro gastrointestinal digestion assay provided selenium bioaccessibility values of 100 ± 3% and 40 ± 1% for white and wholemeal Se-enriched bread, respectively, being selenomethionine the main bioaccessible Se species in white bread, while in wholemeal bread this compound was undetectable.

  2. Functionality of soymilk powder and its components in fresh soy bread.

    PubMed

    Nilufer, D; Boyacioglu, D; Vodovotz, Y

    2008-05-01

    The physicochemical changes upon addition of soymilk powder (SMP) to soy bread were investigated. Two-pound loaves of soy bread were produced with components (soluble fiber [SF], insoluble fiber [ISF], soy protein) that mimic those levels contributed by SMP. Soy flour and soy flour/SMP soy breads served as controls. The following were determined for all breads produced: physical properties (loaf volume, crust, and crumb color); chemical compositions (SF and ISF contents, protein and ash contents); and physicochemical properties (water activity, total moisture content by thermogravimetric analysis [TGA], "freezable" water [FW], "unfreezable" water [UFW] content by DSC, stiffness at 25 degrees C by dynamic mechanical analysis [DMA], and firmness with Instron testing machine). SMP contained significant amounts of SF aside from the ISF fraction and mostly denatured soy protein. SMP addition to soy bread formulation significantly decreased loaf volume with respect to control soy bread, which can be attributed to the ISF and SPI contents of this ingredient. Other effects of SMP were found to be lighter and yellowish crumb color, darker crust color, and increase in firmness, as well as no change in moisture content, FW and UFW contents, water activity, and stiffness parameters.

  3. Bioavailability of Microencapsulated Iron from Fortified Bread Assessed Using Piglet Model

    PubMed Central

    Bryszewska, Malgorzata A.; Laghi, Luca; Zannoni, Augusta; Gianotti, Andrea; Barone, Francesca; Taneyo Saa, Danielle L.; Bacci, Maria L.; Ventrella, Domenico; Forni, Monica

    2017-01-01

    The aim of this study was to investigate the influence of oral iron supplementation, in the form of fortified breads, on the growth performance, health, iron status parameters, and fecal metabolome of anemic piglets. A study was conducted on 24 hybrid (Large White × Landrace × Duroc) piglets. From day 44, the post-natal 12 piglets were supplemented with 100 g of one of two experimental breads, each fortified with 21 mg of ferrous sulphate, either encapsulated or not. After one week of oral supplementation, hematological parameters (hematocrit value, hemoglobin, and red blood cells) showed statistically significant differences (p ≤ 0.05). Piglets fed with the fortified breads had higher iron concentrations in the heart, liver, and intestinal mucosa compared to anemic piglets fed with control bread. Gene expression of hepcidin, iron exporter ferroportin (IREG1), and divalent metal transporter 1 (DMT1), together with concentrations of plasma ferritin, showed no significant statistical differences between groups. Both fortified breads could be used as sources of bioavailable iron. The seven-day intervention trial showed microencapsulation to have only a mild effect on the effectiveness of iron supplementation in the form of fortified bread. PMID:28335378

  4. Gamma processing of Arabic bread for immune system-compromised cancer patients

    SciTech Connect

    Grecz, N.; Brannon, R.; Jaw, R.; Al-Harithy, R.; Hahn, E.W.

    1985-12-01

    Arabic bread prepared from local Saudi flour contained a total of up to 105/sup 4/ organisms per g. Most of these were bacterial spores that survived the baking process (1.3 x 10/sup 2/ to 3.5 x 10/sup 3/) and a small number of yeasts and molds (10 to 40 cells per g). The organisms in Arabic bread appear to be harmless to healthy individuals. However, for immune system-compromised cancer patients and bone marrow transplant recipients, it is prudent to irradiate the bread to reduce microbial contamination. The decimal reduction doses (10% survival) for the most radiation-resistant organisms (spore formers) in bread were 0.11 to 0.15 Mrad. Accordingly, 0.6 Mrad was sufficient to reduce the number of spores in Arabic bread by a factor of 10,000, i.e., to <1/g. This treatment constitutes radiation pasteurization (radicidation), and to this extent, provides a margin of microbiological safety. Sensory evaluation by the nine-point hedonic scale showed no detectable loss of organoleptic quality of bread up to 0.6 Mrad, while irradiation to 2.5 Mrad induced unacceptable organoleptic changes.

  5. Combined effect of sourdough lactic acid bacteria and additives on bread firmness and staling.

    PubMed

    Corsetti, A; Gobbetti, M; De Marco, B; Balestrieri, F; Paoletti, F; Russi, L; Rossi, J

    2000-07-01

    The effect of various sourdoughs and additives on bread firmness and staling was studied. Compared to the bread produced with Saccharomyces cerevisiae 141, the chemical acidification of dough fermented by S. cerevisiae 141 or the use of sourdoughs increased the volume of the breads. Only sourdough fermentation was effective in delaying starch retrogradation. The effect depended on the level of acidification and on the lactic acid bacteria strain. The effect of sourdough made of S. cerevisiae 141-Lactobacillus sanfranciscensis 57-Lactobacillus plantarum 13 was improved when fungal alpha-amylase or amylolytic strains such as L. amylovorus CNBL1008 or engineered L. sanfranciscensis CB1 Amy were added. When pentosans or pentosans, endoxylanase enzyme, and L. hilgardii S32 were added to the same sourdough, a greater delay of the bread firmness and staling was found. When pentosans were in part hydrolyzed by the endoxylanase enzyme, the bread also had the highest titratable acidity, due to the fermentation of pentoses by L. hilgardii S32. The addition of the bacterial protease to the sourdough increased the bread firmness and staling.

  6. Evaluation of Antibacterial Activity of Lactobacillus Spp. on Selected Food Spoilage Bacteria.

    PubMed

    Sharma, Anurag; Gupta, Piyush; Bhattacharya, Susinjan

    2015-01-01

    This study was done to isolate Lactobacillus species from curd, amla/Indian gooseberry and orange and to assess their antagonistic ability against selected food spoilage bacteria, Escherichia coli, Pseudomonas spp. and Bacillus spp. isolated from natural food sources. In the approaches used, native Lactobacillus spp. were isolated from amla, orange and curd and identified by standard microbiological methods. Their antagonistic affect was tested by disc diffusion tests against three selected test isolates, Escherichia coli, Pseudomonas and Bacillus spp. isolated from tomato, pumpkin, cauliflower, lady's finger, carrot, and milk. There are recent patents also suggesting use of novel strains of Lactobacillus for microbial antagonism. In our present work, the lactobacilli isolated from different food sources showed varied ability to inhibit the growth of test isolates. The growth of test isolates was inhibited by Lactobacillus isolates with one of the Lactobacillus isolate from amla being the most potent inhibitor.

  7. Comparing PTR-MS profile of milk inoculated with pure or mixed cultures of spoilage bacteria.

    PubMed

    Alothman, Mohammad; Lusk, Karen A; Silcock, Patrick; Bremer, Phil J

    2017-06-01

    The volatile organic compounds (VOCs) associated with UHT milk (n=8) inoculated with either pure inoculums of Pseudomonas fluorescens (two strains tested) or Chryseobacterium sp., or with mixed cultures of 2 or all 3 of the bacterial strains, and held at 4.5 °C for up to 26 days was measured using proton transfer reaction - mass spectrometry (PTR-MS). The VOCs evolved included a range of carbonyl compounds, alcohols, esters, and acids and had significant qualitative and quantitative differences between the inoculums. Milks inoculated with paired (mixed) bacterial cultures attained patterns similar to the VOC composition of one of the pure inoculums, which could be attributed to the domination of these bacteria within the mixed inoculum. This study will help to characterize the spoilage of milk and provide important insights into understanding the factors that limit the shelf life of milk.

  8. A pigment-producing spoilage bacterium responsible for violet discoloration of refrigerated market milk and cream.

    PubMed

    SEITZ, E W; ELLIKER, P R; SANDINE, W E

    1961-07-01

    A psychrophilic strain of bacteria identified as Chromobacterium lividum was established as the causative agent of an outbreak of violet discoloration in refrigerated, pasteurized retail milk and cream. The organism was rod-shaped, gram-negative, and produced viscid colonies with abundant violet pigment on Tryptone glucose yeast extract agar. Growth was abundant at 4 C but none occurred at 37 C. Growth in milk was characterized by a dark violet ring at the surface after a few days, and the deep violet color gradually extended through the product in older cultures. Some proteolysis occurred. The pigment appeared to be similar to that of other known species of Chromobacterium and assisted in identification of the genus of the causative organism. The isolated strain of C. lividum was destroyed by exposure to 56 C for 5 min which suggested postpasteurization contamination as the source of the spoilage organism in commercial milk and cream.

  9. Interaction of monolaurin, eugenol and sodium citrate on growth of common meat spoilage and pathogenic organisms.

    PubMed

    Blaszyk, M; Holley, R A

    1998-02-17

    Interactions of monolaurin, eugenol (phenolic compound) and sodium citrate (chelator) on the growth of six organisms including common meat spoilage (Lactobacillus curvatus, Lactobacillus sake, Leuconostoc mesenteroides, Brochothrix thermosphacta) and pathogenic (Escherichia coli O157:H7 and Listeria monocytogenes) organisms were investigated. The combinations of 100 to 250 ppm monolaurin with 500 and 1000 ppm eugenol, and 0.2 and 0.4% sodium citrate were more effective than each component separately. More than one combination prevented detectable growth of each organism. Lactic acid bacteria (LAB) and E. coli O157:H7 were most resistant and L. monocytogenes and B. thermosphacta most sensitive to control by the chosen combinations. The presence of sodium citrate was necessary to yield potent inhibition of Lb. curvatus and Lb. sake growth by the monolaurin and eugenol combinations.

  10. Low-Temperature Production of Urocanic Acid by Spoilage Bacteria Isolated from Mahimahi (Coryphaena hippurus).

    PubMed

    Baranowski, J D

    1985-08-01

    Urocanic acid production was studied in 166 bacterial cultures isolated from mahimahi which had been stored for 14 days on ice in seawater. After 4 days of incubation at 10 degrees C in histidine-supplemented Trypticase soy broth (BBL Microbiology Systems, Cockeysville, Md.), urocanic acid was measured by thin-layer chromatography. Fifty-eight of the cultures were positive for urocanic acid, with the eight most active isolates producing ca. 10 mg/100 ml. These observations, coupled with a report that urocanic acid may be the predominant histidine metabolite in fish held at low temperatures, all suggest that urocanic acid may be a useful alternative to histamine as a spoilage index in scombroid and other fish that are rich in endogenous histidine.

  11. Effects of morphological changes in beer-spoilage lactic acid bacteria on membrane filtration in breweries.

    PubMed

    Asano, Shizuka; Suzuki, Koji; Iijima, Kazumaru; Motoyama, Yasuo; Kuriyama, Hidetoshi; Kitagawa, Yasushi

    2007-10-01

    Membrane filter performance was investigated using beer-spoilage lactic acid bacteria (LAB). As a result, beer-adapted LAB strains showed considerably increased penetration rate through filters, as compared with non-adapted strains. Further statistical analyses demonstrated the significant shifts in cell size distribution towards shorter rods, when Lactobacillus brevis and L. lindneri strains were precultured in beer. These results indicate that diminished cell size is responsible for the deteriorated filter performance and, therefore, beer-adapted lactic acid bacteria are regarded as a serious threat to the production of unpasteurized beers. In addition, the selection of test strains and preculture conditions are suggested to be important for the rigorous and standardized evaluation of membrane filter performance in the brewing industry.

  12. At-Line Methods for Controlling Microbial Growth and Spoilage in Meat Processing Abattoirs

    NASA Astrophysics Data System (ADS)

    Fung, Daniel Y. C.; Edwards, Jessica R.; Crozier-Dodson, Beth Ann

    Many decontamination strategies are available to the meat industry for the control of spoilage and disease causing microorganisms. Most of these strategies are spraywash methods, and a variety of other methods are becoming increasingly popular in the industry as new research and developments are made. Hide-on decontamination has been shown to be extremely effective for controlling pathogens and may become more commonly incorporated into the hazard analysis and critical control point (HACCP) plans. A comprehensive review of decontamination of Escherichia coli O157:H7 in meat processing was made by Edwards and Fung (2006). The current chapter is for at-line consideration of all types of microorganisms related to meat processing with E. coli O157:H7 as the main model. Another detailed analysis of the entire topic of meat safety was made by Fung et al.

  13. Degradation of pectic compounds during pasteurised vegetable juice spoilage by Chryseomonas luteola: a predictive microbiology approach.

    PubMed

    Membré, J M; Kubaczka, M

    1998-07-21

    Predictive modelling consists in describing effects of environmental factors on microbial growth parameters. With food spoilage bacteria, this approach must be extended to both growth and food damage characterisation. In order to study the incidence of storage temperature on vegetable damage, using predictive microbiology tools, kinetics of pectic compound degradation were studied. Chryseomonas luteola has been chosen because of its ability to grow on post-harvested vegetables. Experiments were performed at refrigerated temperatures (0-10 degrees C) with low initial bacterial charges (10(1)-10(3.5) cfu/ml). Microbial specific growth rate (mu), stability phase before pectic degradation (Sp) and alteration percentage (Ap) were chosen as reference parameters. Then, sub-optimal temperature effects on these three parameters were estimated using modified Ratkowsky model. Results obtained in synthetic medium were compared with data observed in endive juice to appreciate the alteration of vegetable during post-harvest storage.

  14. Improvement of gluten-free bread properties by the incorporation of bovine plasma proteins and different saccharides into the matrix.

    PubMed

    Rodriguez Furlán, Laura T; Pérez Padilla, Antonio; Campderrós, Mercedes E

    2015-03-01

    The aim of this work was to improve the quality of gluten-free bread, incorporating plasma bovine proteins concentrated by ultrafiltration and freeze-dried with saccharides (inulin and sucrose). The influence of these compounds on textural properties and final bread quality was assessed. The textural studies revealed that with the addition of proteins and inulin, homogeneous and smaller air cells were achieved improving the textural properties while the bread hardness was comparable with breads with gluten. The volume of gluten-free breads increased with increasing proteins and inulin concentrations, reaching a maximum at a protein concentration of 3.5% (w/w). The addition of the enhancers improved moisture retention of the loaves after cooking and an increase of lightness of crumb with respect to the control was observed. The sensory analysis found no statistically significant difference in sensory attributes evaluated with respect to the control, so these ingredients do not negatively affect the organoleptic properties of bread.

  15. The rheology, microstructure and sensory characteristics of a gluten-free bread formulation enhanced with orange pomace.

    PubMed

    O'Shea, Norah; Doran, Linda; Auty, Mark; Arendt, Elke; Gallagher, Eimear

    2013-12-01

    The present manuscript studied a previously optimised gluten-free bread formulation containing 5.5% orange pomace (OP) in relation to the batter characteristics (i.e. pre-baking), microstructure (of the flours, batter and bread) and sensory characteristics of the bread. Rheology, RVA and mixolab results illustrated that orange pomace improved the robustness of the gluten-free batter and decreased the occurrence of starch gelatinisation. This was confirmed from the confocal laser scanning microscopy (CLSM) images, which showed potato starch granules to be more expanded in the control batter when compared to the sample containing orange pomace. Starch granules were also observed to be more enlarged and swollen in the CLSM bread images, suggesting a higher level of gelatinisation occurred in the control sample. Sensory analysis was carried out on the optimised and control bread; panellists scored the flavour, crumb appearance and overall acceptability of the OP-containing breads comparable to the control.

  16. Intake of whole-grain and fiber-rich rye bread versus refined wheat bread does not differentiate intestinal microbiota composition in Finnish adults with metabolic syndrome.

    PubMed

    Lappi, Jenni; Salojärvi, Jarkko; Kolehmainen, Marjukka; Mykkänen, Hannu; Poutanen, Kaisa; de Vos, Willem M; Salonen, Anne

    2013-05-01

    Whole-grain (WG) foods rich in indigestible carbohydrates are thought to modulate the composition of the intestinal microbiota. We investigated in a randomized, parallel, 2-arm 12-wk intervention whether consumption of WG and fiber-rich rye breads compared with refined wheat breads affected the microbiota composition in Finnish individuals aged 60 ± 6 y with metabolic syndrome. Fecal samples from 51 participants (25 males, 26 females) before and after the intervention were processed for the microbiota analysis using a phylogenetic microarray and quantitative polymerase chain reactions targeting the 16S rRNA gene. The intake of whole grains calculated from food records was higher in the group consuming rye breads (75 g) than in that consuming refined wheat breads (4 g; P < 0.001), confirmed by fasting plasma alkylrecorsinol concentrations, a biomarker of whole grain intake. The intestinal microbiota composition did not significantly differ between the groups after the intervention. However, we detected a 37% decrease of Bacteroidetes (P < 0.05) in parallel to a 53% decrease in the alkylrecorsinol concentration (P < 0.001) in the group consuming refined wheat breads. In this group, the abundance of bacteria related to Bacteroides vulgatus, B. plebeius, and Prevotella tannerae decreased, whereas that of bacteria related to Collinsella and members of the Clostridium clusters IV and XI increased. In a multivariate regression analysis, the abundance of Bacteroides spp. was best explained by different fat compounds among dietary variables, whereas the main sugar-converting butyrate-producers were mostly associated with the intake of whole- and refined-grain bread and fiber. Our results indicate that the quality of grains has a minor effect on the intestinal microbiota composition in participants with metabolic syndrome and suggest that the dietary influence on the microbiota involves other dietary components such as fat.

  17. The Fate of Acetic Acid during Glucose Co-Metabolism by the Spoilage Yeast Zygosaccharomyces bailii

    PubMed Central

    Rodrigues, Fernando; Sousa, Maria João; Ludovico, Paula; Santos, Helena; Côrte-Real, Manuela; Leão, Cecília

    2012-01-01

    Zygosaccharomyces bailii is one of the most widely represented spoilage yeast species, being able to metabolise acetic acid in the presence of glucose. To clarify whether simultaneous utilisation of the two substrates affects growth efficiency, we examined growth in single- and mixed-substrate cultures with glucose and acetic acid. Our findings indicate that the biomass yield in the first phase of growth is the result of the weighted sum of the respective biomass yields on single-substrate medium, supporting the conclusion that biomass yield on each substrate is not affected by the presence of the other at pH 3.0 and 5.0, at least for the substrate concentrations examined. In vivo 13C-NMR spectroscopy studies showed that the gluconeogenic pathway is not operational and that [2−13C]acetate is metabolised via the Krebs cycle leading to the production of glutamate labelled on C2, C3 and C4. The incorporation of [U-14C]acetate in the cellular constituents resulted mainly in the labelling of the protein and lipid pools 51.5% and 31.5%, respectively. Overall, our data establish that glucose is metabolised primarily through the glycolytic pathway, and acetic acid is used as an additional source of acetyl-CoA both for lipid synthesis and the Krebs cycle. This study provides useful clues for the design of new strategies aimed at overcoming yeast spoilage in acidic, sugar-containing food environments. Moreover, the elucidation of the molecular basis underlying the resistance phenotype of Z. bailii to acetic acid will have a potential impact on the improvement of the performance of S. cerevisiae industrial strains often exposed to acetic acid stress conditions, such as in wine and bioethanol production. PMID:23285028

  18. Microbiological spoilage and investigation of volatile profile during storage of sea bream fillets under various conditions.

    PubMed

    Parlapani, Foteini F; Mallouchos, Athanasios; Haroutounian, Serkos A; Boziaris, Ioannis S

    2014-10-17

    Volatile organic compound (VOC) profile was determined during storage of sea bream (Sparus aurata) fillets under air and Modified Atmosphere Packaging (MAP - CO2/O2/N2: 60/10/30) at 0, 5 and 15°C. Microbiological, TVB-N (Total Volatile Base Nitrogen) and sensory changes were also monitored. Shelf-life of sea bream fillets stored under air was 14, 5 and 2days (d) at 0, 5 and 15°C respectively, while under MAP was 18, 8, and 2d at 0, 5 and 15°C respectively. At the end of shelf life, the total microbial population ranged from 7.5 to 8.5logcfu/g. Pseudomonas spp. were among the dominant spoilage microorganisms in all cases, however growth of Brochothrix thermosphacta and Lactic Acid Bacteria (LAB) were favoured under MAP compared to air. TVB-N production was favoured at higher temperatures and under air compared to lower temperatures and MAP. TVB-N increased substantially from the middle of storage and its value never reached concentrations higher than 30-35mgN/100g, which is the legislation limit, making it a poor chemical spoilage index (CSI). A lot of alcohols, aldehydes, ketones and ethyl esters that were detected in the present study have been reported as bacterial metabolites, others as products of chemical oxidation while others as aroma constituents. VOCs such as 3-methylbutanal, acetic acid, ethanol, ethyl esters of isovaleric and 2-methylbutyric acids, 1-penten-3-ol, 1-octen-3-ol and cis-4-heptenal appeared from the early or middle stages and increased until the end of storage. From those only 3-methylbutanal, acetic acid, ethanol and the ethyl esters have been reported as microbial origin, making them potential CSI candidates of sea bream fillets.

  19. Physiological characterization of spoilage strains of Zygosaccharomyces bailii and Zygosaccharomyces rouxii isolated from high sugar environments.

    PubMed

    Martorell, Patricia; Stratford, Malcolm; Steels, Hazel; Fernández-Espinar, Ma Teresa; Querol, Amparo

    2007-03-10

    Two isolates of spoilage yeasts Zygosaccharomyces bailii and Zygosaccharomyces rouxii were obtained from a high sugar environment, in a factory producing candied fruit and nougat. Other strains, Z. bailii from other environments and other isolates from high sugar/salt environments were obtained for comparison (Zygosaccharomyces lentus, Candida magnoliae, Candida halophila and Pichia guilliermondii). A full physiological assessment of these isolates was carried out, of preservative and biocide resistance, osmotolerance, ethanol-tolerance, low pH resistance, degree of fermentation, and growth temperature and survival to pasteurisation. Results showed that the strains isolated from high sugar environments did not show extreme physiology. These were robust strains but within the normal parameters expected for the species. One exception to this was that the Z. bailii strains were abnormally able to grow at 37 degrees C. In all strains other than C. magnolia and C. halophila, cells were able to adapt to high levels of sugar. Cultures grown in high glucose concentrations were subsequently able to tolerate higher concentrations of glucose than previously. Similarly, high sugar was found to confer a degree of protection against pasteurisation, enabling survival in what would have otherwise been a lethal treatment. Isolates of Z. bailii showed a high level of resistance to preservatives such as sorbic acid, benzoic acid, acetic acid, cinnamic acid, and ethanol, and also to heat. Unexpectedly Z. bailii isolates were not exceptionally resistant to biocides such as peracetic acid, or hypochlorite. These results indicate that spoilage by yeasts such as Z. bailii may be better prevented by use of biocidal cleaning agents in the factory, rather than treating the food with preservatives.

  20. Toxigenic genes, spoilage potential, and antimicrobial resistance of Bacillus cereus group strains from ice cream.

    PubMed

    Arslan, Seza; Eyi, Ayla; Küçüksarı, Rümeysa

    2014-02-01

    Bacillus spp. can be recovered from almost every environment. It is also found readily in foods, where it may cause food spoilage and/or food poisoning due to its toxigenic and pathogenic nature, and extracellular enzymes. In this study, 29 Bacillus cereus group strains from ice cream were examined for the presence of following virulence genes hblC, nheA, cytK and ces genes, and tested for a range of the extracellular enzymes, and antimicrobial susceptibility. The strains were found to produce extracellular enzymes: proteolytic and lipolytic activity, gelatin hydrolysis and lecithinase production (100%), DNase production (93.1%) and amylase activity (93.1%). Of 29 strains examined, 24 (82.8%) showed hemolytic activity on blood agar. Beta-lactamase enzyme was only produced by 20.7% of B. cereus group. Among 29 B. cereus group from ice cream, nheA was the most common virulence gene detected in 44.8% of the strains, followed by hblC gene with 17.2%. Four (13.8%) of the 29 strains were positive for both hblC gene and nheA gene. Contrarily, cytK and ces genes were not detected in any of the strains. Antimicrobial susceptibility of ice cream isolates was tested to 14 different antimicrobial agents using the disc diffusion method. We detected resistance to penicillin and ampicillin with the same rate of 89.7%. Thirty-one percent of the strains were multiresistant to three or more antibiotics. This study emphasizes that the presence of natural isolates of Bacillus spp. harboring one or more enterotoxin genes, producing extracellular enzymes which may cause spoilage and acquiring antibiotic resistance might hold crucial importance in the food safety and quality.

  1. The fate of acetic acid during glucose co-metabolism by the spoilage yeast Zygosaccharomyces bailii.

    PubMed

    Rodrigues, Fernando; Sousa, Maria João; Ludovico, Paula; Santos, Helena; Côrte-Real, Manuela; Leão, Cecília

    2012-01-01

    Zygosaccharomyces bailii is one of the most widely represented spoilage yeast species, being able to metabolise acetic acid in the presence of glucose. To clarify whether simultaneous utilisation of the two substrates affects growth efficiency, we examined growth in single- and mixed-substrate cultures with glucose and acetic acid. Our findings indicate that the biomass yield in the first phase of growth is the result of the weighted sum of the respective biomass yields on single-substrate medium, supporting the conclusion that biomass yield on each substrate is not affected by the presence of the other at pH 3.0 and 5.0, at least for the substrate concentrations examined. In vivo(13)C-NMR spectroscopy studies showed that the gluconeogenic pathway is not operational and that [2-(13)C]acetate is metabolised via the Krebs cycle leading to the production of glutamate labelled on C(2), C(3) and C(4). The incorporation of [U-(14)C]acetate in the cellular constituents resulted mainly in the labelling of the protein and lipid pools 51.5% and 31.5%, respectively. Overall, our data establish that glucose is metabolised primarily through the glycolytic pathway, and acetic acid is used as an additional source of acetyl-CoA both for lipid synthesis and the Krebs cycle. This study provides useful clues for the design of new strategies aimed at overcoming yeast spoilage in acidic, sugar-containing food environments. Moreover, the elucidation of the molecular basis underlying the resistance phenotype of Z. bailii to acetic acid will have a potential impact on the improvement of the performance of S. cerevisiae industrial strains often exposed to acetic acid stress conditions, such as in wine and bioethanol production.

  2. Oxygen requirements of the food spoilage yeast Zygosaccharomyces bailii in synthetic and complex media.

    PubMed

    Rodrigues, F; Côrte-Real, M; Leão, C; van Dijken, J P; Pronk, J T

    2001-05-01

    Most yeast species can ferment sugars to ethanol, but only a few can grow in the complete absence of oxygen. Oxygen availability might, therefore, be a key parameter in spoilage of food caused by fermentative yeasts. In this study, the oxygen requirement and regulation of alcoholic fermentation were studied in batch cultures of the spoilage yeast Zygosaccharomyces bailii at a constant pH, pH 3.0. In aerobic, glucose-grown cultures, Z. bailii exhibited aerobic alcoholic fermentation similar to that of Saccharomyces cerevisiae and other Crabtree-positive yeasts. In anaerobic fermentor cultures grown on a synthetic medium supplemented with glucose, Tween 80, and ergosterol, S. cerevisiae exhibited rapid exponential growth. Growth of Z. bailii under these conditions was extremely slow and linear. These linear growth kinetics indicate that cell proliferation of Z. bailii in the anaerobic fermentors was limited by a constant, low rate of oxygen leakage into the system. Similar results were obtained with the facultatively fermentative yeast Candida utilis. When the same experimental setup was used for anaerobic cultivation, in complex YPD medium, Z. bailii exhibited exponential growth and vigorous fermentation, indicating that a nutritional requirement for anaerobic growth was met by complex-medium components. Our results demonstrate that restriction of oxygen entry into foods and beverages, which are rich in nutrients, is not a promising strategy for preventing growth and gas formation by Z. bailii. In contrast to the growth of Z. bailii, anaerobic growth of S. cerevisiae on complex YPD medium was much slower than growth in synthetic medium, which probably reflected the superior tolerance of the former yeast to organic acids at low pH.

  3. Pulsed-light inactivation of pathogenic and spoilage bacteria on cheese surface.

    PubMed

    Proulx, J; Hsu, L C; Miller, B M; Sullivan, G; Paradis, K; Moraru, C I

    2015-09-01

    Cheese products are susceptible to postprocessing cross-contamination by bacterial surface contamination during slicing, handling, or packaging, which can lead to food safety issues and significant losses due to spoilage. This study examined the effectiveness of pulsed-light (PL) treatment on the inactivation of the spoilage microorganism Pseudomonas fluorescens, the nonenterohemorrhagic Escherichia coli ATCC 25922 (nonpathogenic surrogate of Escherichia coli O157:H7), and Listeria innocua (nonpathogenic surrogate of Listeria monocytogenes) on cheese surface. The effects of inoculum level and cheese surface topography and the presence of clear polyethylene packaging were evaluated in a full factorial experimental design. The challenge microorganisms were grown to early stationary phase and subsequently diluted to reach initial inoculum levels of either 5 or 7 log cfu/slice. White Cheddar and process cheeses were cut into 2.5×5 cm slices, which were spot-inoculated with 100 µL of bacterial suspension. Inoculated cheese samples were exposed to PL doses of 1.02 to 12.29 J/cm(2). Recovered survivors were enumerated by standard plate counting or the most probable number technique, as appropriate. The PL treatments were performed in triplicate and data were analyzed using a general linear model. Listeria innocua was the least sensitive to PL treatment, with a maximum inactivation level of 3.37±0.2 log, followed by P. fluorescens, with a maximum inactivation of 3.74±0.8 log. Escherichia coli was the most sensitive to PL, with a maximum reduction of 5.41±0.1 log. All PL inactivation curves were nonlinear, and inactivation reached a plateau after 3 pulses (3.07 J/cm(2)). The PL treatments through UV-transparent packaging and without packaging consistently resulted in similar inactivation levels. This study demonstrates that PL has strong potential for decontamination of the cheese surface.

  4. Lactococcus lactis and Lactobacillus sakei as bio-protective culture to eliminate Leuconostoc mesenteroides spoilage and improve the shelf life and sensorial characteristics of commercial cooked bacon.

    PubMed

    Comi, Giuseppe; Andyanto, Debbie; Manzano, Marisa; Iacumin, Lucilla

    2016-09-01

    Cooked bacon is a typical Italian meat product. After production, cooked bacon is stored at 4 ± 2 °C. During storage, the microorganisms that survived pasteurisation can grow and produce spoilage. For the first time, we studied the cause of the deterioration in spoiled cooked bacon compared to unspoiled samples. Moreover, the use of bio-protective cultures to improve the quality of the product and eliminate the risk of spoilage was tested. The results show that Leuconostoc mesenteroides is responsible for spoilage and produces a greening colour of the meat, slime and various compounds that result from the fermentation of sugars and the degradation of nitrogen compounds. Finally, Lactococcus lactis spp. lactis and Lactobacillus sakei were able to reduce the risk of Leuconostoc mesenteroides spoilage.

  5. Use of selected sourdough strains of Lactobacillus for removing gluten and enhancing the nutritional properties of gluten-free bread.

    PubMed

    Di Cagno, Raffaella; Rizzello, Carlo G; De Angelis, Maria; Cassone, Angela; Giuliani, Giammaria; Benedusi, Anna; Limitone, Antonio; Surico, Rosalinda F; Gobbetti, Marco

    2008-07-01

    Forty-six strains of sourdough lactic acid bacteria were screened for proteolytic activity and acidification rate in gluten-free (GF) flours. The sourdough cultures consisted of Lactobacillus sanfranciscensis LS40 and LS41 and Lactobacillus plantarum CF1 and were selected and used for the manufacture of GF bread. Fermentation occurred in two steps: (i) long-time fermentation (16 h) and (ii) fast fermentation (1.5 h) using the previous fermented sourdough as inoculum (ca. 43%, wt/wt) with Saccharomyces cerevisiae (baker's yeast). GF bread started with baker's yeast alone was used as the control. Gluten was added to ingredients before fermentation to simulate contamination. Initial gluten concentration of 400 ppm was degraded to below 20 ppm only in the sourdough GF bread. Before baking, sourdough GF bread showed phytase activity ca. sixfold higher than that of GF bread started with baker's yeast alone. Atomic absorption spectrophotometric analysis revealed that the higher phytase activity resulted in an increased availability of free Ca2+, Zn2+, and Mg2+. The concentration of free amino acids also was the highest in sourdough GF bread. Sourdough GF bread had a higher specific volume and was less firm than GF bread started with baker's yeast alone. This study highlighted the use of selected sourdough cultures to eliminate risks of contamination by gluten and to enhance the nutritional properties of GF bread.

  6. Development of a bread delivery vehicle for dietary prebiotics to enhance food functionality targeted at those with metabolic syndrome

    PubMed Central

    Costabile, Adele; Walton, Gemma E; Tzortzis, George; Vulevic, Jelena; Charalampopoulos, Dimitris; Gibson, Glenn R

    2015-01-01

    Prebiotics are dietary carbohydrates that favourably modulate the gut microbiota. The aims of the present study were to develop a functional prebiotic bread using Bimuno®, (galactooligosaccharide (B-GOS) mixture), for modulation of the gut microbiota in vitro in individuals at risk of metabolic syndrome. A control bread, (no added prebiotic) and positive control bread (containing equivalent carbohydrate to B-GOS bread) were also developed. A 3-stage continuous in vitro colonic model was used to assess prebiotic functionality of the breads. Bacteria were quantified by fluorescence in situ hybridization and short chain fatty acids by gas chromatography. Ion-exchange chromatography was used to determine GOS concentration after bread production. Following B-GOS bread fermentation numbers of bifidobacteria and lactobacilli were significantly higher compared to controls. There was no significant degradation of B-GOS during bread manufacture, indicating GOS withstood the manufacturing process. Furthermore, based on previous research, increased bifidobacteria and butyrate levels could be of benefit to those with obesity related conditions. Our findings support utilization of prebiotic enriched bread for improving gastrointestinal health. PMID:26099034

  7. Development of a bread delivery vehicle for dietary prebiotics to enhance food functionality targeted at those with metabolic syndrome.

    PubMed

    Costabile, Adele; Walton, Gemma E; Tzortzis, George; Vulevic, Jelena; Charalampopoulos, Dimitris; Gibson, Glenn R

    2015-01-01

    Prebiotics are dietary carbohydrates that favourably modulate the gut microbiota. The aims of the present study were to develop a functional prebiotic bread using Bimuno®, (galactooligosaccharide (B-GOS) mixture), for modulation of the gut microbiota in vitro in individuals at risk of metabolic syndrome. A control bread, (no added prebiotic) and positive control bread (containing equivalent carbohydrate to B-GOS bread) were also developed. A 3-stage continuous in vitro colonic model was used to assess prebiotic functionality of the breads. Bacteria were quantified by fluorescence in situ hybridization and short chain fatty acids by gas chromatography. Ion-exchange chromatography was used to determine GOS concentration after bread production. Following B-GOS bread fermentation numbers of bifidobacteria and lactobacilli were significantly higher compared to controls. There was no significant degradation of B-GOS during bread manufacture, indicating GOS withstood the manufacturing process. Furthermore, based on previous research, increased bifidobacteria and butyrate levels could be of benefit to those with obesity related conditions. Our findings support utilization of prebiotic enriched bread for improving gastrointestinal health.

  8. Toxigenic fungi: which are important?

    PubMed

    Pitt, J I

    2000-01-01

    Growth of commonly occurring filamentous fungi in foods may result in production of mycotoxins, which can cause a variety of ill effects in humans, from allergic responses to immunosuppression and cancer. According to experts, five kinds of mycotoxins are important in human health around the world: aflatoxins, ochratoxin A, fumonisins, certain trichothecenes, and zearalenone. These toxins are produced by only a few species of fungi, in a limited range of commodities. Aflatoxins are potent carcinogens, produced by Aspergillus flavus and A. parasiticus in peanuts, maize and some other nuts and oilseeds. Ochratoxin A is a kidney toxin and probable carcinogen. It is produced by Penicillium verrucosum in cereal grains in cold climates, by A. carbonarius in grapes, wines and vine fruits, and by A. ochraceus sometimes in coffee beans. Fumonisins, which may cause oesophageal cancer, are formed by Fusarium moniliforme and F. proliferatum, but only in maize. Trichothecenes are highly immunosuppressive and zearalenone causes oestrogenic effects; both are produced by F. graminearum and related species. Current reporting probably underestimates the effect of mycotoxins as a cause of human mortality.

  9. Bioprospecting--fuels from fungi.

    PubMed

    Strobel, Gary Allan

    2015-05-01

    The world has a continuing demand and utility for liquid fuels to power its societies. The utilization of crude oil based fuels is leading to a dramatic increase in the CO2 content of the atmosphere which is being related to a dangerously warming earth. Having liquid fuels that are derived from biological sources is one solution to this growing problem since the carbon being utilized is only from recycled sources. Presently, the microbes, having the greatest impact on the world's economies, producing liquid fuel are various yeasts producing ethanol. Other microbial sources need to be sought since ethanol is not the most desirable fuel and yeasts require simple sugars to carry out the fermentation processes. Recently, several endophytic fungi have been described that make hydrocarbons with fuel potential (Mycodiesel). Among others the compounds found in the volatile phases of these cultures include alkanes, branched alkanes, cyclohexanes, cyclopentanes, and alkyl alcohols/ketones, benzenes and polyaromatic hydrocarbons. Most importantly, generally these organisms make hydrocarbons while utilizing complex carbohydrates found in all plant-based agricultural wastes. Also discussed in this review is a rationale for finding hydrocarbon producing endophytes as well as examples of other promising hydrocarbon producers-Nodulisporium spp. which make 1,8-cineole and families of other hydrocarbons. Extremely favorable results of engine and fuel testing experiments recently completed on cineole and other products of Nodulisporium sp. are also presented. Finally, there is a brief discussion on the main limiting steps in the domestication of these fungi.

  10. Germination conditions affect selected quality of composite wheat-germinated brown rice flour and bread formulations.

    PubMed

    Charoenthaikij, Phantipha; Jangchud, Kamolwan; Jangchud, Anuvat; Prinyawiwatkul, Witoon; Tungtrakul, Patcharee

    2010-08-01

    Brown rice has been reported to be more nutritious after germination. Germinated brown rice flours (GBRFs) from different steeping conditions (in distilled water [DI, pH 6.8] or in a buffer solution [pH 3] for either 24 or 48 h at 35 degrees C) were evaluated in this study. GBRF obtained from brown rice steeped at pH 3 for 48 h contained the highest amount of free gamma aminobutyric acid (GABA; 67 mg/100 g flour). The composite flour (wheat-GBRF) at a ratio of 70 : 30 exhibited significantly lower peak viscosity (PV) (56.99 - 132.45 RVU) with higher alpha-amylase activity (SN = 696 - 1826) compared with those of wheat flour (control) (PV = 136.46 RVU and SN = 1976). Bread formulations, containing 30% GBRF, had lower loaf volume and greater hardness (P < 0.05) than the wheat bread. However, the hardness of bread containing 30% GBRF (except at pH 6.8 and 24 h) was significantly lower than that of bread containing 30% nongerminated brown rice flour (BRF). Acceptability scores for aroma, taste, and flavor of breads prepared with or without GBRFs (30% substitution) were not significantly different, with the mean score ranging from 6.1 (like slightly) to 7 (like moderately). Among the bread formulations containing GBRF, the one with GBRF prepared after 24 h steeping at pH 3 had a slightly higher (though not significant) overall liking score (6.8). This study demonstrated that it is feasible to substitute wheat flour with up to 30% GBRF in bread formulation without negatively affecting sensory acceptance. Practical Application: Our previous study revealed that flours from germinated brown rice have better nutritional properties, particularly gamma-aminobutyric acid (GABA), than the nongerminated one. This study demonstrated feasibility of incorporating up to 30% germinated brown rice flour in a wheat bread formulation without negatively affecting sensory acceptance. In the current United States market, this type of bread may be sold as frozen bread which would have a

  11. Isolation of a hop-sensitive variant of Lactobacillus lindneri and identification of genetic markers for beer spoilage ability of lactic acid bacteria.

    PubMed

    Suzuki, Koji; Iijima, Kazumaru; Ozaki, Kazutaka; Yamashita, Hiroshi

    2005-09-01

    We have isolated a hop-sensitive variant of the beer spoilage bacterium Lactobacillus lindneri DSM 20692. The variant lost a plasmid carrying two contiguous open reading frames (ORF s) designated horB(L) and horC(L) that encode a putative regulator and multidrug transporter presumably belonging to the resistance-nodulation-cell division superfamily. The loss of hop resistance ability occurred with the loss of resistance to other drugs, including ethidium bromide, novobiocin, and cetyltrimethylammonium bromide. PCR and Southern blot analysis using 51 beer spoilage strains of various species of lactic acid bacteria (LAB) revealed that 49 strains possessed homologs of horB and horC. No false-positive results have been observed for nonspoilage LAB or frequently encountered brewery isolates. These features are superior to those of horA and ORF 5, previously reported genetic markers for determining the beer spoilage ability of LAB. It was further shown that the combined use of horB/horC and horA is able to detect all 51 beer spoilage strains examined in this study. Furthermore sequence comparison of horB and horC homologs identified in four different beer spoilage species indicates these homologs are 96.6 to 99.5% identical, which is not typical of distinct species. The wide and exclusive distribution of horB and horC homologs among beer spoilage LAB and their sequence identities suggest that the hop resistance ability of beer spoilage LAB has been acquired through horizontal gene transfer. These insights provide a foundation for applying trans-species genetic markers to differentiating beer spoilage LAB including previously unencountered species.

  12. Isolation of a Hop-Sensitive Variant of Lactobacillus lindneri and Identification of Genetic Markers for Beer Spoilage Ability of Lactic Acid Bacteria

    PubMed Central

    Suzuki, Koji; Iijima, Kazumaru; Ozaki, Kazutaka; Yamashita, Hiroshi

    2005-01-01

    We have isolated a hop-sensitive variant of the beer spoilage bacterium Lactobacillus lindneri DSM 20692. The variant lost a plasmid carrying two contiguous open reading frames (ORF s) designated horBL and horCL that encode a putative regulator and multidrug transporter presumably belonging to the resistance-nodulation-cell division superfamily. The loss of hop resistance ability occurred with the loss of resistance to other drugs, including ethidium bromide, novobiocin, and cetyltrimethylammonium bromide. PCR and Southern blot analysis using 51 beer spoilage strains of various species of lactic acid bacteria (LAB) revealed that 49 strains possessed homologs of horB and horC. No false-positive results have been observed for nonspoilage LAB or frequently encountered brewery isolates. These features are superior to those of horA and ORF 5, previously reported genetic markers for determining the beer spoilage ability of LAB. It was further shown that the combined use of horB/horC and horA is able to detect all 51 beer spoilage strains examined in this study. Furthermore sequence comparison of horB and horC homologs identified in four different beer spoilage species indicates these homologs are 96.6 to 99.5% identical, which is not typical of distinct species. The wide and exclusive distribution of horB and horC homologs among beer spoilage LAB and their sequence identities suggest that the hop resistance ability of beer spoilage LAB has been acquired through horizontal gene transfer. These insights provide a foundation for applying trans-species genetic markers to differentiating beer spoilage LAB including previously unencountered species. PMID:16151091

  13. Influence of different shrinking temperatures and vacuum conditions on the ability of psychrotrophic Clostridium to cause 'blown pack' spoilage in chilled vacuum-packaged beef.

    PubMed

    Silva, Alessandra R; Tahara, Ana Cláudia C; Chaves, Rafael D; Sant'Ana, Anderson S; Faria, José de Assis F; Massaguer, Pilar R

    2012-12-01

    This study determined the ability of psychrotrophic Clostridium strains isolated from vacuum-packaged beefs and abattoir environments to cause 'blown-pack' spoilage of vacuum-packaged beef stored at 2 and 15 °C. The influence of shrinking temperatures (83, 84 and 87 °C) and vacuum pressure (6 and 9 mbar) on the occurrence of such spoilage as well as the effects of simulated transportation (500 km) on the integrity of packages was determined. At 15 °C and 2 °C, twelve and six strains caused 'blown-pack' spoilage, respectively. The combination of vacuum pressure (9 mbar) combined with shrinking temperature (87 °C) retarded the occurrence of spoilage. The simulated transportation under the experimental conditions did not affect the integrity of packages. More studies that assess the factors that may contribute for the occurrence of 'blown-pack' spoilage should be performed to avoid the occurrence of such spoilage during its shelf-life.

  14. Long-term fungal inhibitory activity of water-soluble extracts of Phaseolus vulgaris cv. Pinto and sourdough lactic acid bacteria during bread storage.

    PubMed

    Coda, Rossana; Rizzello, Carlo G; Nigro, Franco; De Angelis, Maria; Arnault, Philip; Gobbetti, Marco

    2008-12-01

    The antifungal activity of proteinaceous compounds from different food matrices was investigated. In initial experiments, water-soluble extracts of wheat sourdoughs, cheeses, and vegetables were screened by agar diffusion assays with Penicillium roqueforti DPPMAF1 as the indicator fungus. Water-soluble extracts of sourdough fermented with Lactobacillus brevis AM7 and Phaseolus vulgaris cv. Pinto were selected for further study. The crude water-soluble extracts of L. brevis AM7 sourdough and P. vulgaris cv. Pinto had a MIC of 40 mg of peptide/ml and 30.9 mg of protein/ml, respectively. MICs were markedly lower when chemically synthesized peptides or partially purified protein fractions were used. The water-soluble extract of P. vulgaris cv. Pinto showed inhibition toward a large number of fungal species isolated from bakeries. Phaseolin alpha-type precursor, phaseolin, and erythroagglutinating phytohemagglutinin precursor were identified in the water-soluble extract of P. vulgaris cv. Pinto by nano liquid chromatography-electrospray ionization-tandem mass spectrometry. When the antifungal activity was assayed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, all three proteins were inhibitory. A mixture of eight peptides was identified from the water-soluble extract of sourdough L. brevis AM7, and five of these exhibited inhibitory activity. Bread was made at the pilot plant scale by sourdough fermentation with L. brevis AM7 and addition of the water-soluble extract (27%, vol/wt; 5 mg of protein/ml) of P. vulgaris cv. Pinto. Slices of bread packed in polyethylene bags did not show contamination by fungi until at least 21 days of storage at room temperature, a level of protection comparable to that afforded by 0.3% (wt/wt) calcium propionate.

  15. The Association of Bread and Rice with Metabolic Factors in Type 2 Diabetic Patients

    PubMed Central

    Akhoundan, Mahdieh; Shadman, Zhaleh; Jandaghi, Parisa; Aboeerad, Maryam; Larijani, Bagher; Jamshidi, Zahra; Ardalani, Hamidreza; Khoshniat Nikoo, Mohsen

    2016-01-01

    Purpose Carbohydrates are shown to have an important role in blood glucose control, type 2 diabetes and cardiovascular diseases risk. This is even more challenging when considering populations consuming refined grains diets. Bread and rice are staple foods which supply main proportion of Iranian calorie intake. This study was designed to investigate the effect of bread and rice intake on blood glucose control, lipid profile and anthropometric measurements in Iranian type 2 diabetic patients. Methods 426 patients with type 2 diabetes were included in this study. Anthropometric measurements were done using standard methods. Dietary information was assessed by a valid and reliable food frequency questionnaire (FFQ). Fasting blood glucose (FBG), glycated hemoglobin (HbA1c), serum triglycride (TG), total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol were examined after 12-hour fasting. Results The results represented that people in the highest tertile compared to the lowest tertile of calorie adjusted total bread intake have higher FBG. FBG in the highest tertile of calorie adjusted total bread-rice intake was also significantly higher than the lowest. The association remained significant after adjusting for potential confounders. Rice intake showed no association with cardio-metabolic risk factors. Conclusion We founded that higher total bread intake and total bread-rice intake were associated with FBG in type 2 diabetic patients whereas rice intake was not associated with glucose and lipid profile. This result should be confirmed in prospective studies, considering varieties, glycemic index (GI), glycemic load (GL) and cooking method of bread and rice. PMID:28005914

  16. Identification and Antioxidant Properties of Phenolic Compounds during Production of Bread from Purple Wheat Grains.

    PubMed

    Yu, Lilei; Beta, Trust

    2015-08-26

    Phenolic profiles and antioxidant properties of purple wheat varieties were investigated to document the effects of bread-making. Bread crust and crumb along with samples collected after mixing, 30 min fermenting, 65 min fermenting, and baking were examined. Free phenolic content (105.4 to 113.2 mg FAE/100 g) significantly (p < 0.05) increased during mixing, fermenting, and baking (65% to 68%). Bound phenolics slightly (p > 0.05) decreased after 30 min fermentation (7% to 9%) compared to the dough after mixing, but increased significantly (p < 0.05) during 65 min fermenting and baking (16% to 27%). Their antioxidant activities followed a similar trend as observed for total phenolic content. The bread crust demonstrated increased free (103% to 109%) but decreased bound (2% to 3%) phenolic content, whereas bread crumb exhibited a reversal of these results. Total anthocyanin content (TAC) significantly (p < 0.05) decreased by 21% after mixing; however, it gradually increased to 90% of the original levels after fermenting. Baking significantly (p < 0.05) decreased TAC by 55%, resulting in the lowest value for bread crust (0.8 to 4.4 mg cyn-3-glu equiv./100 g). p-Hydroxybenzoic, vanillic, p-coumaric, and ferulic acids were detected in free-phenolic extracts, while protocatechuic, caffeic syringic, and sinapic were additional acids in bound-phenolic extracts. Cyanidin-3-glucoside was the detectable anthocyanin in purple wheat. Bread-making significantly (p < 0.05) increased the phenolic content and antioxidant activities; however, it compromised the anthocyanin content of purple wheat bread.

  17. Thermophilic Fungi: Their Physiology and Enzymes†

    PubMed Central

    Maheshwari, Ramesh; Bharadwaj, Girish; Bhat, Mahalingeshwara K.

    2000-01-01

    Thermophilic fungi are a small assemblage in mycota that have a minimum temperature of growth at or above 20°C and a maximum temperature of growth extending up to 60 to 62°C. As the only representatives of eukaryotic organisms that can grow at temperatures above 45°C, the thermophilic fungi are valuable experimental systems for investigations of mechanisms that allow growth at moderately high temperature yet limit their growth beyond 60 to 62°C. Although widespread in terrestrial habitats, they have remained underexplored compared to thermophilic species of eubacteria and archaea. However, thermophilic fungi are potential sources of enzymes with scientific and commercial interests. This review, for the first time, compiles information on the physiology and enzymes of thermophilic fungi. Thermophilic fungi can be grown in minimal media with metabolic rates and growth yields comparable to those of mesophilic fungi. Studies of their growth kinetics, respiration, mixed-substrate utilization, nutrient uptake, and protein breakdown rate have provided some basic information not only on thermophilic fungi but also on filamentous fungi in general. Some species have the ability to grow at ambient temperatures if cultures are initiated with germinated spores or mycelial inoculum or if a nutritionally rich medium is used. Thermophilic fungi have a powerful ability to degrade polysaccharide constituents of biomass. The properties of their enzymes show differences not only among species but also among strains of the same species. Their extracellular enzymes display temperature optima for activity that are close to or above the optimum temperature for the growth of organism and, in general, are more heat stable than those of the mesophilic fungi. Some extracellular enzymes from thermophilic fungi are being produced commercially, and a few others have commercial prospects. Genes of thermophilic fungi encoding lipase, protease, xylanase, and cellulase have been cloned and

  18. Use of indirect conductimetry to predict the growth of spoilage yeasts, with special consideration of Zygosaccharomyces bailii.

    PubMed

    Deak, T; Beuchat, L R

    1994-11-01

    In recent years, modeling for the purpose of predicting microbiological spoilage of foods has gained much interest. Predictive modeling requires a concentrated mathematical and experimental approach; to collect data of adequate quality is a technically demanding task when several experimental parameters are involved. Rapid, non-traditional, automated techniques are particularly useful in modeling. Of these, electrometric techniques appear to be most promising. Indirect conductimetry was used to study the effect of temperature, aw, pH and potassium sorbate concentration on the growth of Zygosaccharomyces bailii. The automated Malthus 2000 instrument proved to be convenient for gathering a large amount of data that were then used to develop polynomial models describing the response of the yeast to combinations of experimental factors in terms of conductimetric detection time and maximum rate of change in conductance. Results demonstrated that indirect conductimetry is suitable for monitoring the effect of environmental factors on the growth and activity of Z. bailii and perhaps other food spoilage yeasts.

  19. Evaluation of Clausena anisata essential oil from Cameroon for controlling food spoilage fungi and its potential use as an antiradical agent.

    PubMed

    Yaouba, Aoudou; Tatsadjieu, Léopold Ngoune; Dongmo, Pierre Michel Jazet; Etoa, François Xavier; Mbofung, Carl Moses Fontum; Zollo, Paul Henri Amvam; Menut, Chantal

    2011-09-01

    Investigations were conducted to determine the chemical composition, antifungal and antiradical activities of the essential oil extracted from the fresh leaves of Clausena anisata (Willd.) Hook. F. ex Benth (from Cameroon) against Aspergillus flavus, A. niger, A. parasiticus and Fusarium moniliforme. The essential oil obtained by hydrodistillation was analysed by GC and GC/MS. The disc diffusion method was used to evaluate the fungal growth inhibition at various concentrations of the oil while the antiradical activity of the essential oil was studied by the DPPH (diphenyl picryl hydrazyl) method. The main components obtained were E-ocimenone (15.1%), Z-ocimenone (11.5%), gamma-terpinene (11.4%) and germacrene D (10.9%). After 10 days of incubation on essential oil supplemented medium, the growth of A. flavus, A. niger, A. parasiticus and F. moniliforme were totally inhibited by 4, 5, 5 and 5 mg/mL of C. anisata essential oil, respectively. The antiradical activity of C. anisata essential oil (SC50 = 5.1 g/L) was less than that of butylated hydroxyl toluene (BHT), which was used as the reference compound (SC50 = 0.007 g/L). Results obtained in the present study indicate the possibility of exploiting C. anisata essential oil to fight strains of A. flavus, A. niger, A. parasiticus and F. moniliforme responsible for biodeterioration of stored food products.

  20. Origin and ecological selection of core and food-specific bacterial communities associated with meat and seafood spoilage

    PubMed Central

    Chaillou, Stéphane; Chaulot-Talmon, Aurélie; Caekebeke, Hélène; Cardinal, Mireille; Christieans, Souad; Denis, Catherine; Hélène Desmonts, Marie; Dousset, Xavier; Feurer, Carole; Hamon, Erwann; Joffraud, Jean-Jacques; La Carbona, Stéphanie; Leroi, Françoise; Leroy, Sabine; Lorre, Sylvie; Macé, Sabrina; Pilet, Marie-France; Prévost, Hervé; Rivollier, Marina; Roux, Dephine; Talon, Régine; Zagorec, Monique; Champomier-Vergès, Marie-Christine

    2015-01-01

    The microbial spoilage of meat and seafood products with short shelf lives is responsible for a significant amount of food waste. Food spoilage is a very heterogeneous process, involving the growth of various, poorly characterized bacterial communities. In this study, we conducted 16S ribosomal RNA gene pyrosequencing on 160 samples of fresh and spoiled foods to comparatively explore the bacterial communities associated with four meat products and four seafood products that are among the most consumed food items in Europe. We show that fresh products are contaminated in part by a microbiota similar to that found on the skin and in the gut of animals. However, this animal-derived microbiota was less prevalent and less abundant than a core microbiota, psychrotrophic in nature, mainly originated from the environment (water reservoirs). We clearly show that this core community found on meat and seafood products is the main reservoir of spoilage bacteria. We also show that storage conditions exert strong selective pressure on the initial microbiota: alpha diversity in fresh samples was 189±58 operational taxonomic units (OTUs) but dropped to 27±12 OTUs in spoiled samples. The OTU assemblage associated with spoilage was shaped by low storage temperatures, packaging and the nutritional value of the food matrix itself. These factors presumably act in tandem without any hierarchical pattern. Most notably, we were also able to identify putative new clades of dominant, previously undescribed bacteria occurring on spoiled seafood, a finding that emphasizes the importance of using culture-independent methods when studying food microbiota. PMID:25333463

  1. Bacterial Ecology of Fermented Cucumber Rising pH Spoilage as Determined by Non-Culture Based Methods

    PubMed Central

    Medina, Eduardo; Pérez-Díaz, Ilenys M.; Breidt, Fred; Hayes, Janet; Franco, Wendy; Butz, Natasha; Azcarate-Peril, María Andrea

    2016-01-01

    Fermented cucumber spoilage (FCS) characterized by rising pH and the appearance of manure and cheese like aromas is a challenge of significant economical impact for the pickling industry. Previous culture based studies identified the yeasts Pichia manshurica and Issatchenkia occidentalis, four gram positive bacteria, Lactobacillus buchneri, Lactobacillus parrafaraginis, Clostridium sp. and Propionibacterium and one gram-negative genus, Pectinatus as relevant in various stages of FCS given their ability to metabolize lactic acid. It was the objective of this study to augment the current knowledge of FCS using culture independent methods to microbiologically characterize commercial spoilage samples. Ion Torrent data and 16S rRNA cloning library analyses of samples collected from commercial fermentation tanks confirmed the presence of L. rapi and L. buchneri and revealed the presence of additional species involved in the development of FCS such as Lactobacillus namurensis, Lactobacillus acetotolerans, Lactobacillus panis, Acetobacter peroxydans, Acetobacter aceti, and Acetobacter pasteurianus at pH below 3.4. The culture independent analyses also revealed the presence of species of Veillonella and Dialister in spoilage samples with pH above 4.0 and confirmed the presence of Pectinatus spp. during lactic acid degradation at the higher pH. Acetobacter spp. were successfully isolated from commercial samples collected from tanks subjected to air purging by plating on Mannitol Yeast Peptone agar. In contrast, Lactobacillus spp. were primarily identified in samples of FCS collected from tanks not subjected to air purging for more than 4 months. Thus, it is speculated that oxygen availability may be a determining factor in the initiation of spoilage and the leading microbiota. Practical Application Understanding of the underlying microbiology and biochemistry driving FCS is essential to enhancing the sodium chloride (NaCl)-free cucumber fermentation technology and in

  2. The Biodiversity of the Microbiota Producing Heat-Resistant Enzymes Responsible for Spoilage in Processed Bovine Milk and Dairy Products.

    PubMed

    Machado, Solimar G; Baglinière, François; Marchand, Sophie; Van Coillie, Els; Vanetti, Maria C D; De Block, Jan; Heyndrickx, Marc

    2017-01-01

    Raw bovine milk is highly nutritious as well as pH-neutral, providing the ideal conditions for microbial growth. The microbiota of raw milk is diverse and originates from several sources of contamination including the external udder surface, milking equipment, air, water, feed, grass, feces, and soil. Many bacterial and fungal species can be found in raw milk. The autochthonous microbiota of raw milk immediately after milking generally comprises lactic acid bacteria such as Lactococcus, Lactobacillus, Streptococcus, and Leuconostoc species, which are technologically important for the dairy industry, although they do occasionally cause spoilage of dairy products. Differences in milking practices and storage conditions on each continent, country and region result in variable microbial population structures in raw milk. Raw milk is usually stored at cold temperatures, e.g., about 4°C before processing to reduce the growth of most bacteria. However, psychrotrophic bacteria can proliferate and contribute to spoilage of ultra-high temperature (UHT) treated and sterilized milk and other dairy products with a long shelf life due to their ability to produce extracellular heat resistant enzymes such as peptidases and lipases. Worldwide, species of Pseudomonas, with the ability to produce these spoilage enzymes, are the most common contaminants isolated from cold raw milk although other genera such as Serratia are also reported as important milk spoilers, while for others more research is needed on the heat resistance of the spoilage enzymes produced. The residual activity of extracellular enzymes after high heat treatment may lead to technological problems (off flavors, physico-chemical instability) during the shelf life of milk and dairy products. This review covers the contamination patterns of cold raw milk in several parts of the world, the growth potential of psychrotrophic bacteria, their ability to produce extracellular heat-resistant enzymes and the consequences for

  3. The Biodiversity of the Microbiota Producing Heat-Resistant Enzymes Responsible for Spoilage in Processed Bovine Milk and Dairy Products

    PubMed Central

    Machado, Solimar G.; Baglinière, François; Marchand, Sophie; Van Coillie, Els; Vanetti, Maria C. D.; De Block, Jan; Heyndrickx, Marc

    2017-01-01

    Raw bovine milk is highly nutritious as well as pH-neutral, providing the ideal conditions for microbial growth. The microbiota of raw milk is diverse and originates from several sources of contamination including the external udder surface, milking equipment, air, water, feed, grass, feces, and soil. Many bacterial and fungal species can be found in raw milk. The autochthonous microbiota of raw milk immediately after milking generally comprises lactic acid bacteria such as Lactococcus, Lactobacillus, Streptococcus, and Leuconostoc species, which are technologically important for the dairy industry, although they do occasionally cause spoilage of dairy products. Differences in milking practices and storage conditions on each continent, country and region result in variable microbial population structures in raw milk. Raw milk is usually stored at cold temperatures, e.g., about 4°C before processing to reduce the growth of most bacteria. However, psychrotrophic bacteria can proliferate and contribute to spoilage of ultra-high temperature (UHT) treated and sterilized milk and other dairy products with a long shelf life due to their ability to produce extracellular heat resistant enzymes such as peptidases and lipases. Worldwide, species of Pseudomonas, with the ability to produce these spoilage enzymes, are the most common contaminants isolated from cold raw milk although other genera such as Serratia are also reported as important milk spoilers, while for others more research is needed on the heat resistance of the spoilage enzymes produced. The residual activity of extracellular enzymes after high heat treatment may lead to technological problems (off flavors, physico-chemical instability) during the shelf life of milk and dairy products. This review covers the contamination patterns of cold raw milk in several parts of the world, the growth potential of psychrotrophic bacteria, their ability to produce extracellular heat-resistant enzymes and the consequences for

  4. A microbial spoilage profile of half shell Pacific oysters (Crassostrea gigas) and Sydney rock oysters (Saccostrea glomerata).

    PubMed

    Madigan, Thomas L; Bott, Nathan J; Torok, Valeria A; Percy, Nigel J; Carragher, John F; de Barros Lopes, Miguel A; Kiermeier, Andreas

    2014-04-01

    This study aimed to assess bacterial spoilage of half shell Pacific and Sydney rock oysters during storage using microbial culture and 16S rRNA pyrosequencing. Odour and pH of oyster meats were also investigated. Estimation of microbiological counts by microbial culture highlighted growth of psychrotrophic bacteria. During storage, odour scores (a score describing deterioration of fresh odours where a score of 1 is fresh and 4 is completely spoiled) increased from 1.0 to 3.0 for Pacific oysters and from 1.3 to 3.4 for Sydney rock oysters. pH results obtained for both species fluctuated during storage (range 6.28-6.73) with an overall increase at end of storage. Pyrosequencing revealed that the majority of bacteria at Day 0 represented taxa from amongst the Proteobacteria, Tenericutes and Spirochaetes that have not been cultured and systematically described. During storage, Proteobacteria became abundant with Pseudoalteromonas and Vibrio found to be dominant in both oyster species at Day 7. Analysis of the pyrosequencing data showed significant differences in bacterial profiles between oyster species and storage time (both P = 0.001). As oysters spoiled, bacterial profiles between oyster species became more similar indicating a common spoilage profile. Data presented here provides detailed insight into the changing bacterial profile of shucked oysters during storage and has identified two genera, Pseudoalteromonas and Vibrio, as being important in spoilage of shucked oysters.

  5. Lactococcus piscium: a psychrotrophic lactic acid bacterium with bioprotective or spoilage activity in food-a review.

    PubMed

    Saraoui, T; Leroi, F; Björkroth, J; Pilet, M F

    2016-10-01

    The genus Lactococcus comprises 12 species, some known for decades and others more recently described. Lactococcus piscium, isolated in 1990 from rainbow trout, is a psychrotrophic lactic acid bacterium, probably disregarded because most of the strains are unable to grow at 30°C. During the last 10 years, this species has been isolated from a large variety of food: meat, seafood and vegetables, mostly packed under vacuum (VP) or modified atmosphere (MAP) and stored at chilled temperature. Recently, culture-independent techniques used for characterization of microbial ecosystems have highlighted the importance of Lc. piscium in food. Its role in food spoilage varies according to the strain and the food matrix. However, most studies have indicated that Lc. piscium spoils meat, whereas it does not degrade the sensory properties of seafood. Lactococcus piscium strains have a large antimicrobial spectrum, including Gram-positive and negative bacteria. In various seafoods, some strains have a protective effect against spoilage and can extend the sensory shelf-life of the products. They can also inhibit the growth of Listeria monocytogenes, by a cell-to-cell contact-dependent. This article reviews the physiological and genomic characteristics of Lc. piscium and discusses its spoilage or protective activities in food.

  6. Effect of high-oxygen and oxygen-free modified atmosphere packaging on the spoilage process of poultry breast fillets.

    PubMed

    Rossaint, Sonja; Klausmann, Sonja; Kreyenschmidt, Judith

    2015-01-01

    A comparison was made of the effect of atmospheres containing high oxygen (70% O2 and 30% CO2) or high nitrogen (70% N2 and 30% CO2) on the spoilage process during storage (at 4°C) of poultry fillets. Four samples of each gas atmosphere were analyzed at 7 sample points during storage. For this analysis, the growth of typical spoilage organisms (Brochothrix thermosphacta, Pseudomonas spp., Enterobacteriaceae, and Lactobacilli spp.) and total viable count (TVC) were analyzed and modeled by using the Gompertz function. Sensory analyses of the poultry samples were carried out by trained sensory panelists to analyze color, odor, texture, drip loss, and general appearance. The composition of the spoilage flora differed between the oxygen-free atmosphere and the high-oxygen atmosphere. Anaerobic conditions favored the growth of Lactobacilli spp., whereas aerobic gas composition favored the growth of B. thermosphacta. However, no significant difference (P<0.05) in TVC and sensory parameters were observed for poultry samples stored under a high-oxygen atmosphere in comparison to a high-nitrogen atmosphere. These results indicate that high-oxygen packaging has no additional beneficial effect on the quality maintenance and shelf life of fresh poultry fillets.

  7. 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.

  8. Factors Affecting Microbial Load and Profile of Potential Pathogens and Food Spoilage Bacteria from Household Kitchen Tables

    PubMed Central

    Latouche, Melissa Cathleen

    2016-01-01

    The aim was to study the bacterial load and isolate potential pathogens and food spoilage bacteria from kitchen tables, including preparation tables and dining tables. Methods. A total of 53 households gave their consent for participation. The samples were collected by swabbing over an area of 5 cm by 5 cm of the tables and processed for bacterial count which was read as colony forming units (CFU), followed by isolation and identification of potential pathogens and food spoilage bacteria. Result. Knowledge about hygiene was not always put into practice. Coliforms, Enterococcus spp., Pseudomonas spp., Proteus spp., and S. aureus were detected from both dining and preparation tables. The mean CFU and presence of potential pathogens were significantly affected by the hygienic practices of the main food handler of the house, materials of kitchen tables, use of plastic covers, time of sample collection, use of multipurpose sponges/towels for cleaning, and the use of preparation tables as chopping boards (p < 0.05). Conclusion. Kitchen tables could be very important source of potential pathogens and food spoilage bacteria causing foodborne diseases. Lack of hygiene was confirmed by presence of coliforms, S. aureus, and Enterococcus spp. The use of plastic covers, multipurpose sponges, and towels should be discouraged. PMID:27446220

  9. Susceptibility of Pediococcus isolates to antimicrobial compounds in relation to hop-resistance and beer-spoilage

    PubMed Central

    2009-01-01

    Background Though important in the context of food microbiology and as potential pathogens in immuno-compromised humans, bacterial isolates belonging to the genus Pediococcus are best known for their association with contamination of ethanol fermentation processes (beer, wine, or fuel ethanol). Use of antimicrobial compounds (e.g., hop-compounds, Penicillin) by some industries to combat Pediococcus contaminants is long-standing, yet knowledge about the resistance of pediococci to antimicrobial agents is minimal. Here we examined Pediococcus isolates to determine whether antibiotic resistance is associated with resistance to hops, presence of genes known to correlate with beer spoilage, or with ability to grow in beer. Results Lactic acid bacteria susceptibility test broth medium (LSM) used in combination with commercially available GPN3F antimicrobial susceptibility plates was an effective method for assessing antimicrobial susceptibility of Pediococcus isolates. We report the finding of Vancomycin-susceptible Pediococcus isolates from four species. Interestingly, we found that hop-resistant, beer-spoilage, and beer-spoilage gene-harbouring isolates had a tendency to be more susceptible, rather than more resistant, to antimicrobial compounds. Conclusion Our findings indicate that the mechanisms involved in conferring hop-resistance or ability to spoil beer by Pediococcus isolates are not associated with resistance to antibiotics commonly used for treatment of human infections. Also, Vancomycin-resistance was found to be isolate-specific and not intrinsic to the genus as previously believed. PMID:19735560

  10. In-Package Inactivation of Pathogenic and Spoilage Bacteria Associated with Poultry Using Dielectric Barrier Discharge-Cold Plasma Treatments.

    PubMed

    Rothrock, Michael J; Zhuang, Hong; Lawrence, Kurt C; Bowker, Brian C; Gamble, Gary R; Hiett, Kelli L

    2017-02-01

    The goal of this study was to test the efficacy of in-package dielectric barrier discharge-cold plasma (DBD-CP) treatment to inactivate poultry-associated spoilage (Pseudomonas fluorescens) and pathogenic (Salmonella enterica Typhimurium, Campylobacter jejuni) bacteria. Liquid cultures of the bacterial isolates were sealed within packages containing ambient air (Trial 1) or modified air (65% O2:30% CO2:5% N2; Trial 2). The packages were subjected to treatment times ranging from 30 to 180 s, and after 24 h incubation at 4 °C, bacterial titers were determined. The DBD-CP system completely inactivated the four isolates tested, although the in-package gas composition and treatment times were isolate-specific. Both C. jejuni isolates were completely inactivated between 30 s (modified air) and 120 s (ambient air), while modified air was required for the complete inactivation of S. typhimurium (90 s) and P. fluorescens (180 s). This DBD-CP system is effective for inactivating major poultry-associated spoilage and pathogenic bacteria in liquid culture, and through this study, system parameters to optimize inactivation were determined. This study demonstrates the potential for DBD-CP treatment to inactivate major bacteria of economic interest to the poultry industry, thus potentially allowing for reduced spoilage (e.g., longer shelf life) and increased safety of poultry products.

  11. Factors Affecting Microbial Load and Profile of Potential Pathogens and Food Spoilage Bacteria from Household Kitchen Tables.

    PubMed

    Biranjia-Hurdoyal, Susheela; Latouche, Melissa Cathleen

    2016-01-01

    The aim was to study the bacterial load and isolate potential pathogens and food spoilage bacteria from kitchen tables, including preparation tables and dining tables. Methods. A total of 53 households gave their consent for participation. The samples were collected by swabbing over an area of 5 cm by 5 cm of the tables and processed for bacterial count which was read as colony forming units (CFU), followed by isolation and identification of potential pathogens and food spoilage bacteria. Result. Knowledge about hygiene was not always put into practice. Coliforms, Enterococcus spp., Pseudomonas spp., Proteus spp., and S. aureus were detected from both dining and preparation tables. The mean CFU and presence of potential pathogens were significantly affected by the hygienic practices of the main food handler of the house, materials of kitchen tables, use of plastic covers, time of sample collection, use of multipurpose sponges/towels for cleaning, and the use of preparation tables as chopping boards (p < 0.05). Conclusion. Kitchen tables could be very important source of potential pathogens and food spoilage bacteria causing foodborne diseases. Lack of hygiene was confirmed by presence of coliforms, S. aureus, and Enterococcus spp. The use of plastic covers, multipurpose sponges, and towels should be discouraged.

  12. 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.

  13. Healthy Bread Initiative: Methods, Findings, and Theories—Isfahan Healthy Heart Program

    PubMed Central

    Talaei, Mohammad; Khaje, Mohammad-Reza; Sarrafzadegan, Nizal; Sajjadi, Firoozeh; Alikhasi, Hasan; Maghroun, Maryam; Iraji, Farhad; Ehteshami, Shahram

    2013-01-01

    The scientific evidences show that the content, baking methods, and types of bread can make health impacts. Bread, as a major part of Iranian diet, demonstrates a significant potential to be targeted as health promotion subject. Healthy Food for Healthy Communities (HFHC) was a project of Isfahan Healthy Heart Program (IHHP), consisting of a wide variety of strategies, like Healthy Bread (HB) Initiative. The HB Initiative was designed to improve the behaviour of both producers and consumers, mainly aiming at making high-fibre, low-salt bread, eliminating the use of baking soda, providing enough rest time for dough before baking (at least one hour), and enough baking time (at least one minute in oven). A workshop was held for volunteer bakers, and a baker-to-baker training protocol under direct supervision was designed for future volunteers. Cereal Organization was persuaded to provide less refined flour that contained more bran. Health messages in support of new breads were disseminated by media and at bakeries by health professionals. Evaluation of the HB Initiative was done using before-after assessments and population surveys. While HB was baked in 1 (0.01%) bakery at baseline, 402 (41%) bakeries in the intervention area joined the HB Initiative in 2009. Soda was completely eliminated and fibre significantly increased from 4±0.4 g% before study to 12±0.6 g% after the intervention (p<0.001). The preparation and baking times remarkably increased. Wastage of bread decreased from 13±1.8 g% to 2±0.5 g% and was expressed as the most important advantage of this initiative by consumers. People who lived in Isfahan city consumed whole bread 6 times more than those who lived in reference area Arak (p<0.001). The HB Initiative managed to add new breads as a healthy choice that were compatible with local dishes and made a model to solve the long-standing problems of bread. It used various health promotion approaches but was best consistent with Beattie's model. PMID

  14. Healthy bread initiative: methods, findings, and theories--Isfahan Healthy Heart Program.

    PubMed

    Talaei, Mohammad; Mohammadifard, Noushin; Khaje, Mohammad-Reza; Sarrafzadegan, Nizal; Sajjadi, Firoozeh; Alikhasi, Hasan; Maghroun, Maryam; Iraji, Farhad; Ehteshami, Shahram

    2013-03-01

    The scientific evidences show that the content, baking methods, and types of bread can make health impacts. Bread, as a major part of Iranian diet, demonstrates a significant potential to be targeted as health promotion subject. Healthy Food for Healthy Communities (HFHC) was a project of Isfahan Healthy Heart Program (IHHP), consisting of a wide variety of strategies, like Healthy Bread (HB) Initiative. The HB Initiative was designed to improve the behaviour of both producers and consumers, mainly aiming at making high-fibre, low-salt bread, eliminating the use of baking soda, providing enough rest time for dough before baking (at least one hour), and enough baking time (at least one minute in oven). A workshop was held for volunteer bakers, and a baker-to-baker training protocol under direct supervision was designed for future volunteers. Cereal Organization was persuaded to provide less refined flour that contained more bran. Health messages in support of new breads were disseminated by media and at bakeries by health professionals. Evaluation of the HB Initiative was done using before-after assessments and population surveys. While HB was baked in 1 (0.01%) bakery at baseline, 402 (41%) bakeries in the intervention area joined the HB Initiative in 2009. Soda was completely eliminated and fibre significantly increased from 4 +/- 0.4 g% before study to 12 +/- 0.6 g% after the intervention (p < 0.001). The preparation and baking times remarkably increased. Wastage of bread decreased from 13 +/- 1.8 g% to 2 +/- 0.5 g% and was expressed as the most important advantage of this initiative by consumers. People who lived in Isfahan city consumed whole bread 6 times more than those who lived in reference area Arak (p < 0.001). The HB Initiative managed to add new breads as a healthy choice that were compatible with local dishes and made a model to solve the longstanding problems of bread. It used various health promotion approaches but was best consistent with Beattie

  15. Comparative Studies on the Fungi and Bio-Chemical Characteristics of Snake Gourd (Trichosanthes curcumerina Linn) and Tomato (Lycopersicon esculentus Mill) in Rivers State, Nigeria

    NASA Astrophysics Data System (ADS)

    Chuku, E. C.; Ogbonna, D. N.; Onuegbu, B. A.; Adeleke, M. T. V.

    Comparative studies on the fungi and biochemical characteristics of Tomatoes (Lycopersicon esculentus Mill) and the Snake gourd (Trichosanthes curcumerina Linn) products were investigated in Rivers State using various analytical procedures. Results of the proximate analysis of fresh snake gourd and tomatoes show that the essential minerals such as protein, ash, fibre, lipid, phosphorus and niacin contents were higher in snake gourd but low in carbohydrate, calcium, iron, vitamins A and C when compared to the mineral fractions of tomatoes which has high values of calcium, iron, vitamins A and C. The mycoflora predominantly associated with the fruit rot of tomato were Fusarium oxysporium, Fusarium moniliforme, Rhizopus stolonifer and Aspergillus niger, while other fungi isolates from Snake gourd include Rhizopus stolonifer, Aspergillus niger, Aspergillus tamari, Penicillium ita/icum and Neurospora crassa. Rhizopus stolonifer and Aspergillus niger were common spoilage fungi to both the Tomato and Snake gourd. All the fungal isolates were found to be pathogenic. The duration for storage of the fruits at room temperature (28±1°C) showed that Tomato could store for 5 days while Snake gourd stored for as much as 7 days. Sensory evaluation shows that Snake gourd is preferred to Tomatoes because of its culinary and medicinal importance.

  16. Mechanical properties of cottage cheese-fortified wheat dough and loaf bread.

    PubMed

    Guemes-Vera, Norma; Gonzalez-Victoriano, Lizbeth; Soto-Simental, Sergio; Hernandez-Chavez, Juan Francisco; Reyes-Santamaria, Ma Isabel

    2014-10-01

    Milk whey and its derivatives are commonly used to fortify food products. A study was done on the effect of seven cottage cheese (sour/sweet whey mixture) inclusion concentrations (5, 7.5, 10, 12.5, 15, 17.5 and 20 %) on the mechanical properties of white wheat bread dough using a texture analyser. Cottage cheese protein content was 10.05 %. Loaf bread made using the 7.5, 12.5 and 17.5 % cottage cheese concentrations showed crumb quality similar to the control in the 12.5 and 17.5 % treatments, but more open and less homogeneous in 7.5 % treatment. Cottage cheese concentration affected bread volume, with the higher concentrations lowering volume by up to 50 %, in response to increased water retention. Sensory analysis showed bread containing 7.5 % cottage cheese was not different from the control, with an 83.33 % acceptance rate. The 7.5 % concentration was optimum for white wheat loaf bread production since its mechanical and sensory properties were most similar to the control.

  17. Effect of Salt and Ethanol Addition on Zein-Starch Dough and Bread Quality.

    PubMed

    Smith, Brennan M; Bean, Scott R; Selling, Gordon; Sessa, David; Aramouni, Fadi M

    2017-03-01

    Development of viscoelastic doughs from non-wheat proteins allows for a wider range of gluten-free products. Little work has been completed to describe mechanisms of zein functionality in food systems. To identify factors responsible for dough development in zein-starch mixtures and their influence on zein bread quality, a mixture of 20% zein-80% maize starch was mixed with water and various reagents. Salts, NaSCN, NaCl, and Na2 SO4 were evaluated at concentrations from 0 to 2M for their influence on the properties of zein-starch dough systems. NaSCN at low concentrations produced softer dough. Ethanol treatments produced softer more workable dough in the absence of salts. Increasing concentrations of NaCl and Na2 SO4 resulted in coalescing of the proteins and no dough formation. The addition of β-ME had minimal softening effects on zein-starch dough. Specific volumes of zein-starch bread increased with decreasing NaCl addition in bread formulations. Likewise, including 5% ethanol (v/v) in the bread formula increased bread quality.

  18. Effect of Aspergillus niger xylanase on dough characteristics and bread quality attributes.

    PubMed

    Ahmad, Zulfiqar; Butt, Masood Sadiq; Ahmed, Anwaar; Riaz, Muhammad; Sabir, Syed Mubashar; Farooq, Umar; Rehman, Fazal Ur

    2014-10-01

    The present study was conducted to investigate the impact of various treatments of xylanase produced by Aspergillus niger applied in bread making processes like during tempering of wheat kernels and dough mixing on the dough quality characteristics i.e. dryness, stiffness, elasticity, extensibility, coherency and bread quality parameters i.e. volume, specific volume, density, moisture retention and sensory attributes. Different doses (200, 400, 600, 800 and 1,000 IU) of purified enzyme were applied to 1 kg of wheat grains during tempering and 1 kg of flour (straight grade flour) during mixing of dough in parallel. The samples of wheat kernels were agitated at different intervals for uniformity in tempering. After milling and dough making of both types of flour (having enzyme treatment during tempering and flour mixing) showed improved dough characteristics but the improvement was more prominent in the samples receiving enzyme treatment during tempering. Moreover, xylanase decreased dryness and stiffness of the dough whereas, resulted in increased elasticity, extensibility and coherency and increase in volume & decrease in bread density. Xylanase treatments also resulted in higher moisture retention and improvement of sensory attributes of bread. From the results, it is concluded that dough characteristics and bread quality improved significantly in response to enzyme treatments during tempering as compared to application during mixing.

  19. Effect of hydrocolloids on selected properties of gluten-free dough and bread.

    PubMed

    Sabanis, D; Tzia, C

    2011-08-01

    Addition of hydrocolloids (H/C) in gluten-free (GF) bread formulation is necessary in order to act as polymeric substances that should mimic the viscoelastic properties of gluten and increase the dough's gas-retaining ability. The properties of H/C vary depending on their origin and chemical structure. Addition of H/C (hydroxypropylmethylcellulose (HPMC), xanthan, κ-carrageenan and guar gum) of different origins at 1%, 1.5% and 2% (w/w) in GF formulations based on corn starch and rice flour was carried out to investigate the effects on dough rheology and bread quality. The consistency, viscosity and thermal properties of doughs were evaluated. According to results, 1% and 1.5% addition of H/C (except from xanthan) contributed to bread with higher loaf volume and better color compared to control GF bread as well as to increased shelf life due to its moisture-absorption ability. Sensory evaluation by a trained panel revealed a preference for bread containing 1.5% HPMC because of its loaf volume, appearance and firmness characteristics. The micrographs of the dough showed a continuous matrix between starch and HPMC obtaining a more aerated structure.

  20. Bambara-wheat composite flour: rheological behavior of dough and functionality in bread.

    PubMed

    Erukainure, Ochuko L; Okafor, Jane N C; Ogunji, Akinyele; Ukazu, Happiness; Okafor, Ebele N; Eboagwu, Ijeoma L

    2016-11-01

    The rheological behavior and functional properties of doughs from bambara-wheat composite flour was investigated. Bambara-wheat composite flour was prepared by substituting wheat with 0%, 10%, 15%, and 20% of bambara flour. The rheological behavior of their dough was analyzed with Mixolab. Breads produced from the flour were analyzed for physical characteristics. Organoleptic analysis was carried out by 20 panelists. Mixolab analysis revealed, except for stability time, depreciating values for dough consistency (C1), protein weakening (C2), starch gelatinization (C3), amylase activity (C4), and retrogradation (C5) as the inclusion of bambara flour increased. Physical characteristics of the loaves revealed significant (P < 0.05) decreasing bread volume and increasing specific volume, respectively, as bambara inclusion increased. There was significant (P < 0.05) difference between wheat bread and the bambara-wheat composites in all the studied quality attributes. 15% bambara-wheat composite bread was the most accepted amongst the composite breads. Inclusion of bambara flour improved the protein behavior of the composite, but did not evidently show benefits in the baking characteristics.