Plant extract enhances the viability of Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus acidophilus in probiotic nonfat yogurt.

PubMed

Michael, Minto; Phebus, Randall K; Schmidt, Karen A

2015-01-01

A commercial plant extract (prepared from olive, garlic, onion and citrus extracts with sodium acetate (SA) as a carrier) was evaluated to extend the viability of yogurt starter and probiotic bacteria as a means to enhance the shelf life of live and active culture, probiotic nonfat yogurt. Yogurts prepared from three different formulas (0.5* plant extract, 0.25* SA, or no supplement) and cultures (yogurt starter plus Bifidobacterium animalis,Lactobacillus acidophilus, or both probiotics) were assessed weekly during 29 days of storage at 5°C. Supplemented yogurt mixes had greater buffering capacities than non-supplemented yogurt mixes. At the end of storage, Lactobacillus bulgaricus and L. acidophilus counts in supplemented yogurts were greater compared with non-supplemented yogurts. Supplementation did not affect Streptococcus thermophilus and B. animalis counts. Hence the greater buffering capacity of yogurt containing plant extract could enhance the longevity of the probiotics, L. bulgaricus and L. acidophilus, during storage.

Plant extract enhances the viability of Lactobacillus delbrueckii subsp. bulgaricus and Lactobacillus acidophilus in probiotic nonfat yogurt

PubMed Central

Michael, Minto; Phebus, Randall K; Schmidt, Karen A

2015-01-01

A commercial plant extract (prepared from olive, garlic, onion and citrus extracts with sodium acetate (SA) as a carrier) was evaluated to extend the viability of yogurt starter and probiotic bacteria as a means to enhance the shelf life of live and active culture, probiotic nonfat yogurt. Yogurts prepared from three different formulas (0.5* plant extract, 0.25* SA, or no supplement) and cultures (yogurt starter plus Bifidobacterium animalis,Lactobacillus acidophilus, or both probiotics) were assessed weekly during 29 days of storage at 5°C. Supplemented yogurt mixes had greater buffering capacities than non-supplemented yogurt mixes. At the end of storage, Lactobacillus bulgaricus and L. acidophilus counts in supplemented yogurts were greater compared with non-supplemented yogurts. Supplementation did not affect Streptococcus thermophilus and B. animalis counts. Hence the greater buffering capacity of yogurt containing plant extract could enhance the longevity of the probiotics, L. bulgaricus and L. acidophilus, during storage. PMID:25650127

Probiotic culture survival and implications in fermented frozen yogurt characteristics.

PubMed

Davidson, R H; Duncan, S E; Hackney, C R; Eigel, W N; Boling, J W

2000-04-01

Low-fat ice cream mix was fermented with probiotic-supplemented and traditional starter culture systems and evaluated for culture survival, composition, and sensory characteristics of frozen product. Fermentations were stopped when the titratable acidity reached 0.15% greater than the initial titratable acidity (end point 1) or when the pH reached 5.6 (end point 2). Mix was frozen and stored for 11 wk at -20 degrees C. The traditional yogurt culture system contained the strains Streptococcus salivarius ssp. thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. The probiotic-supplemented system contained the traditional cultures as well as Bifidobacterium longum and Lactobacillus acidophilus. We compared recovery of Bifodobacterium by three methods, a repair-detection system with roll-tubes and plates on modified bifid glucose medium and plates with maltose + galactose reinforced clostridial medium. Culture bacteria in both systems did not decrease in the yogurt during frozen storage. The roll-tube method with modified bifid glucose agar and repair detection system provided at least one-half log10 cfu/ml higher recovery of B. longum compared with recoveries using modified bifid glucose agar or maltose + galactose reinforced clostridial agar on petri plates. No change in concentrations of lactose or protein for products fermented with either culture system occurred during storage. Acid flavor was more intense when product was fermented to pH 5.6, but yogurt flavor was not intensified. The presence of probiotic bacteria in the supplemented system seemed to cause no differences in protein and lactose concentration and sensory characteristics.

Inhibitory effect of essential oils against Lactobacillus rhamnosus and starter culture in fermented milk during its shelf-life period

PubMed Central

Moritz, Cristiane Mengue Feniman; Rall, Vera Lúcia Mores; Saeki, Margarida Júri; Júnior, Ary Fernandes

2012-01-01

The use of essential oils in foods has attracted great interest, due to their antagonistic action against pathogenic microorganisms. However, this action is undesirable for probiotic foods, as products containing Lactobacillus rhamnosus. The aim of the present study was to measure the sensitivity profile of L. rhamnosus and a yogurt starter culture in fermented milk, upon addition of increasing concentrations of cinnamon, clove and mint essential oils. Essential oils were prepared by steam distillation, and chemically characterised by gas chromatography-mass spectrometry (GC-MS) and determination of density. Survival curves were obtained from counts of L. rhamnosus and the starter culture (alone and in combination), upon addition of 0.04% essential oils. In parallel, titratable acidity was monitored over 28 experimental days. Minimum inhibitory concentration values, obtained using the microdilution method in Brain Heart Infusion medium, were 0.025, 0.2 and 0.4% for cinnamon, clove and mint essential oils, respectively. Cinnamon essential oil had the highest antimicrobial activity, especially against the starter culture, interfering with lactic acid production. Although viable cell counts of L. rhamnosus were lower following treatment with all 3 essential oils, relative to controls, these results were not statistically significant; in addition, cell counts remained greater than the minimum count of 108CFU/mL required for a product to be considered a probiotic. Thus, although use of cinnamon essential oil in yogurt makes starter culture fermentation unfeasible, it does not prevent the application of L. rhamnosus to probiotic fermented milk. Furthermore, clove and mint essential oil caused sublethal stress to L. rhamnosus. PMID:24031939

Study on beta-galactosidase enzymatic activity of herbal yogurt.

PubMed

Chowdhury, Banani Ray; Chakraborty, Runu; Raychaudhuri, Utpal

2008-03-01

Different types of herbal yogurts were developed by mixing standardized milk with pretreated herbs, namely tulsi leaf (Ocimum sanctum), pudina leaf (Mentha arvensis) and coriander leaf (Coriandrum sativum), with leaves separately and a 1:1 (v/v) mixture of the strains of lactic starter cultures---Lactobacillus acidophilus (NCIM 2903) and Lactobacillus plantarum (NCIM 2083)-followed by incubation at 40 degrees C for 6 h. The beta-galactosidase enzymatic activity of the abovementioned herbal yogurts was determined and interestingly noted to exhibit higher enzymatic activity compared with the control yogurt (without any herbs). Among all herbal yogurts, tulsi yogurt had the maximum beta-galactosidase activity.

Characterization and Antioxidant Property of Probiotic and Synbiotic Yogurts.

PubMed

Madhu, Arenahalli Ningegowda; Amrutha, Nanjaiah; Prapulla, Siddalingaiya Gurudutt

2012-06-01

The effect of a prebiotic (fructooligosaccharides) or a synbiotic components (prebiotic and probiotic) on the viability, proteolysis and antioxidant properties of probiotic and synbiotic yogurt during 28 days of storage at 4 °C has been investigated. Yogurt starters in conjunction with either probiotic bacteria Lactobacillus plantarum CFR 2194, Lactobacillus fermentum CFR 2192 and/or fructooligosaccharides (FOS) were used for yogurt preparation. Titratable acidity and pH of all yogurt samples followed a similar pattern of increase or decrease during storage. Proteolysis in synbiotic yogurts was found to be significantly (P < 0.05) higher in comparison with that of control. The addition of prebiotics had no effect (P = 0.17888) on the viability of yogurt starters during cold storage. No observable changes in the viability of probiotic cultures in probiotic groups. However, supplementation of FOS affected the growth significantly (P < 0.05) in promoting the growth of L. plantarum and L. fermentum. Antioxidant activities, the index of nutritional value of yogurt, were monitored. Results showed that the DPPH-radical-scavenging activity (85 %) in synbiotic yogurt containing L. plantarum and FOS was significantly higher (P < 0.05) in comparison with that of control yogurt (72 %). Total phenolics and the ferric reducing power were highest in synbiotic yogurts in comparison with that of other test samples during the entire period of storage. Addition of selected probiotics with FOS thus resulted in an improved functionality of yogurt.

Identification by using MALDI-TOF mass spectrometry of lactic acid bacteria isolated from non-commercial yogurts in southern Anatolia, Turkey.

PubMed

Karaduman, Ayse; Ozaslan, Mehmet Ozaslan; Kilic, Ibrahim H; Bayil-Oguzkan, Sibel; Kurt, Bekir S; Erdogan, Nese

2017-03-01

Yogurt is a dairy product obtained by bacterial fermentation of milk. Commercial yogurts are produced using standard starters while, in the production of non-commercial yogurt, the microbiota is quite different since yogurts are used as starter for years. To determine the final characteristics of the fermented product it is necessary to know the biochemical properties of the starter cultures, such as acidity, aroma and flavor. This can only be achieved by identifying and characterizing the bacteria in starter cultures. In our study, 208 non-commercial yogurt samples were collected from 9 different locations in Anatolia, southern Turkey. Their pH and lactic acid bacteria profiles were analyzed. Isolated bacteria were identified by MALDI-TOF MS (matrix-assisted laser sesorption-ionization time-of-flight, mass spectrometry), which is a fast and reliable method for identification of bacterial isolates compared to classical laboratory methods. In this study, 41% of the isolates were identified by using this method, which is 99.9% and 34.0% confidence. The isolates contained two genera (Enterococcus and Lactobacillus) and four species. Afterwards, the four lactic acid bacteria were characterized physiologically and biochemically and we found that they differed from lactic acid bacteria used in commercial yogurt production. [Int Microbiol 20(1): 25-30 (2017)]. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

Effect of addition of Versagel on microbial, chemical, and physical properties of low-fat yogurt.

PubMed

Ramchandran, L; Shah, N P

2008-09-01

The objective of this study was to examine the effect of Versagel on the growth and proteolytic activity of Streptococcus thermophilus 1275 and Lactobacillus delbrueckii ssp. bulgaricus 1368 and angiotensin-I converting enzyme inhibitory activity of the peptides generated thereby as well as on the physical properties of low-fat yogurt during a storage period of 28 d at 4 degrees C. Three different types of low-fat yogurts, YV0, YV1, and YV2, were prepared using Versagel as a fat replacer. The fermentation time of the low-fat yogurts containing Versagel was less than that of the control yogurt (YV0). The starter cultures maintained their viability (8.68 to 8.81 log CFU/g of S. thermophilus and 8.51 to 8.81 log CFU/g of L. delbrueckii ssp. bulgaricus) in all the yogurts throughout the storage period. There was some decrease in the pH of the yogurts during storage and an increase in the concentration of lactic acid. However, the proteolytic and ACE-inhibitory potential of the starter cultures was suppressed in the presence of Versagel. On the other hand, the addition of Versagel had a positive impact on the physical properties of the low-fat yogurt, namely, spontaneous whey separation, firmness, and pseudoplastic properties.

Starter cultures for kimchi fermentation.

PubMed

Lee, Mo-Eun; Jang, Ja-Young; Lee, Jong-Hee; Park, Hae-Woong; Choi, Hak-Jong; Kim, Tae-Woon

2015-05-01

Kimchi is a traditional Korean vegetable product that is naturally fermented by various microorganisms present in the raw materials. Among these microorganisms, lactic acid bacteria dominate the fermentation process. Natural fermentation with unsterilized raw materials leads to the growth of various lactic acid bacteria, resulting in variations in the taste and quality of kimchi, which may make it difficult to produce industrial-scale kimchi with consistent quality. The use of starter cultures has been considered as an alternative for the industrial production of standardized kimchi, and recent trends suggest that the demand for starter cultures is on the rise. However, several factors should be carefully considered for the successful application of starter cultures for kimchi fermentation. In this review, we summarize recent studies on kimchi starter cultures, describe practical problems in the application of industrial-scale kimchi production, and discuss the directions for further studies.

Technical note: development of a quantitative PCR method for monitoring strain dynamics during yogurt manufacture.

PubMed

Miller, D M; Dudley, E G; Roberts, R F

2012-09-01

Yogurt starter cultures may consist of multiple strains of Lactobacillus delbrueckii ssp. bulgaricus (LB) and Streptococcus thermophilus (ST). Conventional plating methods for monitoring LB and ST levels during yogurt manufacture do not allow for quantification of individual strains. The objective of the present work was to develop a quantitative PCR method for quantification of individual strains in a commercial yogurt starter culture. Strain-specific primers were designed for 2 ST strains (ST DGCC7796 and ST DGCC7710), 1 LB strain (DGCC4078), and 1 Lactobacillus delbrueckii ssp. lactis strain (LL; DGCC4550). Primers for the individual ST and LB strains were designed to target unique DNA sequences in clustered regularly interspersed short palindromic repeats. Primers for LL were designed to target a putative mannitol-specific IIbC component of the phosphotransferase system. Following evaluation of primer specificity, standard curves relating cell number to cycle threshold were prepared for each strain individually and in combination in yogurt mix, and no significant differences in the slopes were observed. Strain balance data was collected for yogurt prepared at 41 and 43°C to demonstrate the potential application of this method. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of production conditions on the stability of a human bifidobacterial species Bifidobacterium longum in yogurt.

PubMed

Abe, F; Tomita, S; Yaeshima, T; Iwatsuki, K

2009-12-01

Human bifidobacteria are more sensitive to external environmental factors than animal bifidobacteria, and it is difficult to ensure their stable survival in yogurt. The purpose of this investigation was to observe the survival of human bifidobacteria in yogurts produced under various production conditions. Frozen or lyophilized bifidobacteria starters containing Bifidobacterium longum BB536 originally isolated from an infant, and commercial lyophilized yogurt starters were used for yogurt preparation. After producing yogurts under various conditions, the survival of bifidobacteria in these yogurts over various storage periods was observed. Although there were some differences in bifidobacterial survival in yogurt between various production conditions, more than 1.0 x 10(7) CFU g(-1) of Bif. longum survived in yogurt after 35 days' storage at 5 degrees C. Lower fermentation temperature (37 degrees C) and inclusion of Lactococcus lactis in the starter significantly (P < 0.05) improved survival of Bif. longum in the yogurt. In this investigation, the human bifidobacterial strain Bif. longum survived adequately in yogurt, although the fermentation temperature and starter composition affect bifidobacterial survival. This investigation indicates that stable probiotic yogurt using human bifidobacteria can be produced by choosing optimal production conditions.

Utilisation of water-in-oil-water (W1/O/W2) double emulsion in a set-type yogurt model for the delivery of probiotic Lactobacillus paracasei.

PubMed

El Kadri, Hani; Lalou, Sofia; Mantzouridou, FaniTh; Gkatzionis, Konstantinos

2018-05-01

W 1 /O/W 2 emulsion in set-type yogurt has the potential to segregate probiotics in order to avoid interference with the starter culture as well as protection against harsh processing and digestion conditions. Lactobacillus paracasei subsp. paracasei DC 412 probiotic cells in milk-based W 1 /O/W 2 emulsions were incorporated in yogurt, in addition to starter cultures Lactobacillus bulgaricus and Streptococcus thermophilus, and the effect on the fermentation, bacterial growth kinetics, physicochemical properties, and structural characteristics was investigated. Stability of W 1 /O/W 2 was monitored with optical microscopy and cryo-SEM and localisation of encapsulated L. paracasei in yogurt was monitored using fluorescent microscopy. During fermentation, starter culture was not affected by introduction of L. paracasei and/or W 1 /O/W 2 emulsion. The viability of L. paracasei encapsulated in W 1 /O/W 2 emulsion was enhanced during storage and after exposure to simulated gastrointestinal conditions. L. paracasei remained within the inner W 1 phase till the end of the storage period (28 days at 4 °C). Moreover, W 1 /O/W 2 emulsion altered physicochemical and textural properties; however, these were within acceptable range. These results demonstrate the capability of W 1 /O/W 2 emulsion to be utilised for probiotic fortification of yogurt to increase functionality without interfering with starter culture and fermentation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparison of Butyric acid concentrations in ordinary and probiotic yogurt samples in Iran.

PubMed

Vaseji, N; Mojgani, N; Amirinia, C; Iranmanesh, M

2012-06-01

Butyric acid has many applications in chemical, food and pharmaceutical industries. Applications of butyric acid are as an additive to food, flavorings, varnishes, perfumes, pharmaceuticals and disinfectants. Butyric acid concentrations have positive impact on the quality control of milk, yogurt and other probiotic dairy products. The present investigation was undertaken to determine and compare the concentrations of butyric acid (C4) in the ordinary and probiotic yogurt samples by GC method. Probiotic yogurt samples were prepared under laboratory scale conditions using two different commercial starters ABY1 and 211, while ordinary yogurt samples lacked the probiotic starter cultures. All samples were analyzed in duplicate, for C4 concentrations by gas chromatography after day 1, 2, 10 and 20 of production, during storage at 4°C. The results were analyzed using ANOVA and Duncan test. The level of the mentioned fatty acid in ABY1 yogurt sample was significantly higher (0.2%) than in 211 samples (0.17%). These values were significantly lower in ordinary yogurt samples and only 0.07% was recorded in these samples on first day of storage which decreased gradually during storage. The level of reduction in the yogurt samples tested during different time intervals was not similar in all the examined samples, and some showed enhanced reduction than other samples. Compared to ordinary yogurt samples, probiotic yogurt samples used in study showed higher levels of butyric acid with increased shelf life.

Comparison of Butyric acid concentrations in ordinary and probiotic yogurt samples in Iran

PubMed Central

Vaseji, N; Mojgani, N; Amirinia, C; Iranmanesh, M

2012-01-01

Background and objectives Butyric acid has many applications in chemical, food and pharmaceutical industries. Applications of butyric acid are as an additive to food, flavorings, varnishes, perfumes, pharmaceuticals and disinfectants. Butyric acid concentrations have positive impact on the quality control of milk, yogurt and other probiotic dairy products. The present investigation was undertaken to determine and compare the concentrations of butyric acid (C4) in the ordinary and probiotic yogurt samples by GC method. Materials and Methods Probiotic yogurt samples were prepared under laboratory scale conditions using two different commercial starters ABY1 and 211, while ordinary yogurt samples lacked the probiotic starter cultures. All samples were analyzed in duplicate, for C4 concentrations by gas chromatography after day 1, 2, 10 and 20 of production, during storage at 4°C. The results were analyzed using ANOVA and Duncan test. Results The level of the mentioned fatty acid in ABY1 yogurt sample was significantly higher (0.2%) than in 211 samples (0.17%). These values were significantly lower in ordinary yogurt samples and only 0.07% was recorded in these samples on first day of storage which decreased gradually during storage. The level of reduction in the yogurt samples tested during different time intervals was not similar in all the examined samples, and some showed enhanced reduction than other samples. Conclusions Compared to ordinary yogurt samples, probiotic yogurt samples used in study showed higher levels of butyric acid with increased shelf life. PMID:22973475

Short communication: Lactose enhances bile tolerance of yogurt culture bacteria.

PubMed

Mena, Behannis; Aryana, Kayanush

2018-03-01

Lactose is an energy source for culture bacteria. Bile tolerance is an important probiotic property. Our aim was to elucidate the effect of lactose on bile tolerance of yogurt starter culture Lactobacillus bulgaricus LB-12 and Streptococcus thermophilus ST-M5. Bile tolerance of pure cultures was determined using 0.3% oxgall in MRS THIO broth (Difco, Becton Dickinson, Sparks, MD) for L. bulgaricus and 0.3% oxgall in M17 broth (Oxoid, Basingstoke, UK) for Strep. thermophilus. Lactose was added to both broths at 0 (control), 1, 3, and 5% (wt/vol) broth. Dilutions were plated hourly for 12 h. Experiments were replicated 3 times. At 2, 4, and 12 h of incubation, lactose incorporated at all amounts, 1, 3, and 5% (wt/vol), showed higher counts of Strep. thermophilus ST-M5 compared with the control. Lactose use at 5% (wt/vol) significantly enhanced bile tolerance of both L. bulgaricus and Strep. thermophilus compared with control. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

7 CFR 58.330 - Butter starter cultures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Butter starter cultures. 58.330 Section 58.330 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.330 Butter starter cultures. Harmless bacterial cultures when used in the development of...

7 CFR 58.330 - Butter starter cultures.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 3 2012-01-01 2012-01-01 false Butter starter cultures. 58.330 Section 58.330... Material § 58.330 Butter starter cultures. Harmless bacterial cultures when used in the development of flavor components in butter and related products shall have a pleasing and desirable flavor and shall...

7 CFR 58.330 - Butter starter cultures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 3 2013-01-01 2013-01-01 false Butter starter cultures. 58.330 Section 58.330... Material § 58.330 Butter starter cultures. Harmless bacterial cultures when used in the development of flavor components in butter and related products shall have a pleasing and desirable flavor and shall...

7 CFR 58.330 - Butter starter cultures.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 3 2014-01-01 2014-01-01 false Butter starter cultures. 58.330 Section 58.330... Material § 58.330 Butter starter cultures. Harmless bacterial cultures when used in the development of flavor components in butter and related products shall have a pleasing and desirable flavor and shall...

7 CFR 58.330 - Butter starter cultures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 3 2011-01-01 2011-01-01 false Butter starter cultures. 58.330 Section 58.330... Material § 58.330 Butter starter cultures. Harmless bacterial cultures when used in the development of flavor components in butter and related products shall have a pleasing and desirable flavor and shall...

Preparation of low galactose yogurt using cultures of Gal(+) Streptococcus thermophilus in combination with Lactobacillus delbrueckii ssp. bulgaricus.

PubMed

Anbukkarasi, Kaliyaperumal; UmaMaheswari, Thiyagamoorthy; Hemalatha, Thiagarajan; Nanda, Dhiraj Kumar; Singh, Prashant; Singh, Rameshwar

2014-09-01

Streptococcus thermophilus is an important lactic starter used in the production of yogurt. Most strains of S. thermophilus are galactose negative (Gal(-)) and are able to metabolize only glucose portion of lactose and expel galactose into the medium. This metabolic defect leads to the accumulation of free galactose in yogurt, resulting in galactosemia among consumers. Hence there is an absolute need to develop low galactose yogurt. Therefore, in this study, three galactose positive (Gal(+)) S. thermophilus strains from National Collection of Dairy Cultures (NCDC) viz. NCDC 659 (AJM), NCDC 660 (JM1), NCDC 661 (KM3) and a reference galactose negative (Gal(-)) S. thermophilus NCDC 218 were used for preparation of low galactose yogurt. In milk fermented using S. thermophilus isolates alone, NCDC 659 released less galactose (0.27 %) followed by NCDC 661 (0.3 %) and NCDC 660 (0.45 %) after 10 h at 42 °C. Milk was fermented in combination with Gal(-) L. delbrueckii subsp. bulgaricus NCDC 04, in which NCDC 659 released least galactose upto 0.49 % followed by NCDC 661 (0.51 %) and NCDC 660 (0.60 %) than reference Gal(-) NCDC 218(0.79 %). Low galactose yogurt was prepared following standard procedure using Gal(+) S. thermophilus isolates and Gal(-) L. delbrueckii subsp. bulgaricus NCDC 04 in 1:1 ratio. Among which low galactose yogurt by NCDC 659 combination contained less galactose 0.37 % followed by NCDC 661 (0.51 %), NCDC 660 (0.65 %) and reference Gal(-) NCDC 218 (0.98 %) after 4 h of fermentation. This study clearly reveals that Gal(+) S. thermophilus isolates can be paired with Gal(-) L. delbrueckii subsp. bulgaricus for developing low galactose yogurt.

Green tea yogurt: major phenolic compounds and microbial growth.

PubMed

Amirdivani, Shabboo; Baba, Ahmad Salihin Hj

2015-07-01

The purpose of this study was to evaluate fermentation of milk in the presence of green tea (Camellia sinensis) with respect to changes in antioxidant activity, phenolic compounds and the growth of lactic acid bacteria. Pasteurized full fat cow's milk and starter culture were incubated at 41 °C in the presence of two different types of green tea extracts. The yogurts formed were refrigerated (4 °C) for further analysis. The total phenolic content was highest (p < 0.05) in air-dried green tea-yogurt (MGT) followed by steam-treated green tea (JGT) and plain yogurts. Four major compounds in MGTY and JGTY were detected. The highest concentration of major phenolic compounds in both samples was related to quercetin-rhamnosylgalactoside and quercetin-3-O-galactosyl-rhamnosyl-glucoside for MGTY and JGTY respectively during first 7 day of storage. Diphenyl picrylhydrazyl and ferric reducing antioxidant power methods showed highest antioxidant capacity in MGTY, JGTY and PY. Streptococcus thermophillus and Lactobacillus spp. were highest in MGTY followed by JGTY and PY. This paper evaluates the implementation of green tea yogurt as a new product with functional properties and valuable component to promote the growth of beneficial yogurt bacteria and prevention of oxidative stress by enhancing the antioxidant activity of yogurt.

Effects of 4 Probiotic Strains in Coculture with Traditional Starters on the Flavor Profile of Yogurt.

PubMed

Tian, Huaixiang; Shen, Yongbo; Yu, Haiyan; He, Yujie; Chen, Chen

2017-07-01

To study the influence of probiotics on the flavor profile of yogurt, 4 probiotics, including Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus casei, were cofermented with traditional starters. The changes of bacterial growth, acid contents and volatile compounds of yogurt were investigated during fermentation and refrigerated storage. The strains that exhibited a low growth rate in milk did not significantly affect the bacterial population dynamics, acidity, or organic acid content during fermentation and storage. However, high viability and enhancement of postacidification were clearly observed in the samples that contained strains with a high growth rate in milk, particularly L. casei. A total of 45 volatile compounds, detected in most samples, were identified by headspace solid-phase micro-extraction followed by gas chromatography-mass spectrometry. Among these compounds, ketones and aldehydes were the most abundant. The presence of either L. rhamnosus or L. plantarum did not significantly affect the major volatile compounds, while contributions of L. casei and L. acidophilus were found in the formation of minor volatile metabolites. Electronic nose measurements exhibited a good discrimination of samples that contained different probiotics during refrigerated storage. © 2017 Institute of Food Technologists®.

Degradation of milk-based bioactive peptides by yogurt fermentation bacteria.

PubMed

Paul, M; Somkuti, G A

2009-09-01

To analyse the effect of cell-associated peptidases in yogurt starter culture strains Lactobacillus delbrueckii ssp. bulgaricus (LB) and Streptococcus thermophilus (ST) on milk-protein-based antimicrobial and hypotensive peptides in order to determine their survival in yogurt-type dairy foods. The 11mer antimicrobial and 12mer hypotensive milk-protein-derived peptides were incubated with mid-log cells of LB and ST, which are required for yogurt production. Incubations were performed at pH 4.5 and 7.0, and samples removed at various time points were analysed by reversed-phase high-performance liquid chromatography (RP-HPLC). The peptides remained mostly intact at pH 4.5 in the presence of ST strains and moderately digested by exposure to LB cells. Peptide loss occurred more rapidly and was more extensive after incubation at pH 7.0. The 11mer and 12mer bioactive peptides may be added at the end of the yogurt-making process when the pH level has dropped to 4.5, limiting the overall extent of proteolysis. The results show the feasibility of using milk-protein-based antimicrobial and hypotensive peptides as food supplements to improve the health-promoting qualities of liquid and semi-solid dairy foods prepared by the yogurt fermentation process.

Influence of lactose hydrolysis on galacto-oligosaccharides, lactose, volatile profile and physicochemical parameters of different yogurt varieties.

PubMed

Vénica, Claudia I; Wolf, Irma V; Bergamini, Carina V; Perotti, María C

2016-12-01

Different types of reduced-lactose yogurt, obtained by lactose hydrolysis using β-galactosidase enzyme, are commercially available. The breakdown of lactose modifies the carbohydrate profile, including the production of prebiotic galacto-oligosaccharides (GOS), which could affect the survival and activity of starter and probiotic cultures and the parameters of yogurt quality. The extension of these changes is dependent on the yogurt matrix composition. This study aimed to evaluate the influence of lactose hydrolysis on GOS, lactose, volatile profile and physicochemical parameters of different yogurt varieties during storage. The presence of β-galactosidase enzyme did not affect either the global composition or the survival of cultures. Overall, the hydrolyzed products had lower acidity than traditional ones. GOS were found at similar levels in fresh hydrolyzed yogurts, whereas in traditional yogurts they were not detected. The proportion of ketones, acids and aldehydes seems to be more dependent on yogurt variety than on addition of the enzyme. Likewise, the storage period affected the volatile fraction to different degree; the increase in acid compounds was more pronounced in hydrolyzed than in traditional yogurts. This work shows that it is possible to obtain different varieties of reduced-lactose yogurt, some of them with additional benefits to health such as reduced fat, reduced calories, added with probiotic/inulin and enriched in GOS, with similar characteristics to traditional products. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Genetically modified starter and protective cultures.

PubMed

Geisen, R; Holzapfel, W H

1996-07-01

Modern approaches towards starter and protective culture improvement rely on advances in molecular biology. For most microorganisms used for food production, gene technological methods have been well developed. By recombinant DNA technology, 'tailor-made' starter and protective cultures may be constructed so as to combine technically desirable features. A single strain which normally would fail to accomplish a given 'task' may now be improved so as to meet a set of requirements necessary for a specific production or preservation process (e.g. wholesomeness, no off-flavour production, overproduction of bacteriocins or particular enzymes). In addition, undesirable properties (e.g. mycotoxin or antibiotic production by cheese moulds) may be eliminated by techniques such as 'gene disruption'.

Effect of inulin and glycerol supplementation on physicochemical properties of probiotic frozen yogurt.

PubMed

Muzammil, Hafiz Shehzad; Rasco, Barbara; Sablani, Shyam

2017-01-01

The present study was designed to investigate the effects of inulin and glycerol supplementation on physicochemical properties of probiotic frozen yogurt. Frozen yogurt was prepared with different types of probiotic ( Lactobacillus acidophilus and Bifidobacterium lactis ) along with yogurt starter culture ( Streptococcus thermophilus and Lactobacillus bulgaricus ). The frozen yogurt mixture was supplemented with inulin (2%, 4%, and 6%) and glycerol (1%, 2%, 3%, and 4%). The results showed that inulin 4% and 6% supplementation increased the overrun by 3% and 5% and the glass transition temperature by 3.3% and 2.8%, and decreased the hardness by 7% and 11%, respectively. Inulin supplementation did not have a significant effect on ice crystal size ( p  > 0.05). Glycerol supplementation increased the stickiness from 2.4% to 18.7%, and decreased the hardness from 8.0% to 14.5% and the glass transition temperature from 2.4% to 34.5%, respectively. Glycerol supplementation did not have a significant effect on overrun or melting rate ( p  > 0.05).

Effect of inulin and glycerol supplementation on physicochemical properties of probiotic frozen yogurt

PubMed Central

Muzammil, Hafiz Shehzad; Rasco, Barbara; Sablani, Shyam

2017-01-01

ABSTRACT The present study was designed to investigate the effects of inulin and glycerol supplementation on physicochemical properties of probiotic frozen yogurt. Frozen yogurt was prepared with different types of probiotic (Lactobacillus acidophilus and Bifidobacterium lactis) along with yogurt starter culture (Streptococcus thermophilus and Lactobacillus bulgaricus). The frozen yogurt mixture was supplemented with inulin (2%, 4%, and 6%) and glycerol (1%, 2%, 3%, and 4%). The results showed that inulin 4% and 6% supplementation increased the overrun by 3% and 5% and the glass transition temperature by 3.3% and 2.8%, and decreased the hardness by 7% and 11%, respectively. Inulin supplementation did not have a significant effect on ice crystal size (p > 0.05). Glycerol supplementation increased the stickiness from 2.4% to 18.7%, and decreased the hardness from 8.0% to 14.5% and the glass transition temperature from 2.4% to 34.5%, respectively. Glycerol supplementation did not have a significant effect on overrun or melting rate (p > 0.05). PMID:28326004

Survival and bioactivities of selected probiotic lactobacilli in yogurt fermentation and cold storage: New insights for developing a bi-functional dairy food.

PubMed

Rutella, Giuseppina Sefora; Tagliazucchi, Davide; Solieri, Lisa

2016-12-01

In previous work, we demonstrated that two probiotic strains, namely Lactobacillus casei PRA205 and Lactobacillus rhamnosus PRA331, produce fermented milks with potent angiotensin-converting enzyme (ACE)-inhibitory and antioxidant activities. Here, we tested these strains for the survivability and the release of antihypertensive and antioxidant peptides in yogurt fermentation and cold storage. For these purposes three yogurt batches were compared: one prepared using yogurt starters alone (Lactobacillus delbrueckii subspecies bulgaricus 1932 and Streptococcus thermophilus 99), and the remaining two containing either PRA205 or PRA331 in addition to yogurt starters. Despite the lower viable counts at the fermentation end compared to PRA331, PRA205 overcame PRA331 in survivability during refrigerated storage for 28 days, leading to viable counts (>10(8) CFU/g) higher than the minimum therapeutic threshold (10(6) CFU/g). Analyses of in vitro ACE-inhibitory and antioxidant activities of peptide fractions revealed that yogurt supplemented with PRA205 displays higher amounts of antihypertensive and antioxidant peptides than that produced with PRA331 at the end of fermentation and over storage. Two ACE-inhibitory peptides, Valine-Proline-Proline (VPP) and Isoleucine-Proline-Proline (IPP), were identified and quantified. This study demonstrated that L. casei PRA205 could be used as adjunct culture for producing bi-functional yogurt enriched in bioactive peptides and in viable cells, which bring health benefits to the host as probiotics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Yogurt made from milk heated at different pH values.

PubMed

Ozcan, Tulay; Horne, David S; Lucey, John A

2015-10-01

Milk for yogurt manufacture is subjected to high heat treatment to denature whey proteins. Low milk pH values (≤ 6.5) at heating result in most denatured whey proteins becoming associated with casein micelles, whereas high milk pH values (≥ 7.0) at heating result in the formation of mostly soluble (nonmicellar) denatured whey protein complexes. There are conflicting reports on the relative importance of soluble and casein-bound whey protein aggregates on the properties of acid gels. Prior studies investigating the effect of pH of milk at heating used model gels in which milk was acidified by glucono-δ-lactone; in this study, we prepared yogurt gels using commercial starter cultures. Model acid gels can have very different texture and physical properties from those made by fermentation with starter cultures. In this study, we investigated the effects of different pH values of milk at heating on the rheological, light backscatter, and microstructural properties of yogurt gels. Reconstituted skim milk was adjusted to pH values 6.2, 6.7, and 7.2 and heated at 85°C for 30 min. A portion of the heated milk samples was readjusted back to pH 6.7 after heating. Milks were inoculated with 3% (wt/wt) yogurt starter culture and incubated at 40°C until pH 4.6. Gel formation was monitored using dynamic oscillatory rheology, and parameters measured included the storage modulus (G') and loss tangent (LT) values. Light-backscattering properties, such as the backscatter ratio (R) and the first derivative of light backscatter ratio (R'), were also monitored during fermentation. Fluorescence microscopy was used to observe gel microstructure. The G' values at pH 4.6 were highest in gels made from milk heated at pH 6.7 and lowest in milk heated at pH 6.2, with or without pH adjustment after heating. The G' values at pH 4.6 were lower in samples after adjustment back to pH 6.7 after heating. No maximum in the LT parameter was observed during gelation for yogurts made from milk

The anti-allergic activity of Lactobacillus plantarum L67 and its application to yogurt.

PubMed

Song, Sooyeon; Lee, Sei-Jung; Park, Dong-June; Oh, Sejong; Lim, Kye-Taek

2016-12-01

Recently, interest in the beneficial role of probiotics in the protection and management of allergic diseases caused by immune disorders has been increasing. This study investigated the inhibitory effect of Lactobacillus plantarum L67 on induced allergic inflammatory response in bisphenol A-treated rat basophilic leukemia 2H3 (RBL-2H3) cells and mouse splenocytes. We also evaluated the applicability of L. plantarum L67 as a yogurt starter culture. We measured the ability of Lactobacillus strains to induce the production of IL-12 and IFN- γ in cultured splenocytes by ELISA. Bisphenol A (50μM)-treated RBL-2H3 cells were cotreated with a glycoprotein (18kDa) isolated from L. plantarum L67 (5-100µg/mL) for 30min. We measured the expression of mitogen-activated protein kinase (ERK and p38), AP-1 (c-Fos and c-Jun), T-bet, and GATA-binding protein 3 (GATA-3) using Western blotting to examine the differentiation of T helper cells. Furthermore, we evaluated the gene expression of IL-1β, IL-6, and IL-10 using real-time quantitative PCR. Finally, we evaluated the applicability of L. plantarum L67 as a yogurt starter by measuring pH, enumeration of bacteria, and sensory scores. Our results showed that L67 protein inhibited the phosphorylation of ERK and p38 mitogen-activated protein kinase through the transcriptional activation of AP-1 in bisphenol A-treated RBL-2H3 cells. During differentiation of T helper cells, the expression of transcription factor GATA-3 was significantly suppressed by L67 protein (100µg/mL) treatment, whereas expression of transcription factor T-bet was increased. In addition, the L67 protein significantly attenuated the expression of T helper 2-linked cytokines IL-1β, IL-6, and IL-10. These results indicate that L. plantarum L67, made available as yogurt starters and dietary supplements, has the potential to prevent allergy-related immune disorders. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights

Use of Protein Hydrolysates in Industrial Starter Culture Fermentations

NASA Astrophysics Data System (ADS)

Ummadi, Madhavi (Soni); Curic-Bawden, Mirjana

Lactic acid bacteria (LAB) have been used as starter cultures for fermenting foods long before the importance of microorganisms were recognized. The most important group of LAB are the lactococci, lactobacilli, streptococci, and pediococci. Additionally, bifidobacteria have been included as a probiotic, providing added value to the product. Since the genera involved are so diverse, the nutritional requirements (energy, carbon and nitrogen sources) differ significantly between and within species. Designing an optimum fermentation medium for production of active and vigorous LAB starter cultures and probiotics requires selecting the right raw ingredients, especially protein hydrolysates that can provide adequate nutrients for growth and viability. This chapter attempts to describe the application of various commercial protein hydrolysates used for production of dairy and meat starter cultures, with special emphasis on meeting the nitrogen requirements of industrially important LAB species.

Enhanced Microbial, Functional and Sensory Properties of Herbal Yogurt Fermented with Korean Traditional Plant Extracts.

PubMed

Joung, Jae Yeon; Lee, Ji Young; Ha, Young Sik; Shin, Yong Kook; Kim, Younghoon; Kim, Sae Hun; Oh, Nam Su

2016-01-01

This study evaluated the effects of two Korean traditional plant extracts (Diospyros kaki THUNB. leaf; DK, and Nelumbo nucifera leaf; NN) on the fermentation, functional and sensory properties of herbal yogurts. Compared to control fermentation, all plant extracts increased acidification rate and reduced the time to complete fermentation (pH 4.5). Supplementation of plant extracts and storage time were found to influence the characteristics of the yogurts, contributing to increased viability of starter culture and phenolic compounds. In particular, the increase in the counts of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was highest (2.95 and 1.14 Log CFU/mL respectively) in DK yogurt. Furthermore, supplementation of the plant extracts significantly influenced to increase the antioxidant activity and water holding capacity and to produce volatile compounds. The higher antioxidant activity and water holding capacity were observed in NN yogurt than DK yogurt. Moreover, all of the sensory characteristics were altered by the addition of plant extracts. Addition of plant extracts increased the scores related to flavor, taste, and texture from plain yogurt without a plant extract, as a result of volatile compounds analysis. Thus, the overall preference was increased by plant extracts. Consequently, supplementation of DK and NN extracts in yogurt enhanced the antioxidant activity and physical property, moreover increased the acceptability of yogurt. These findings demonstrate the possibility of using plant extracts as a functional ingredient in the manufacture of herbal yogurt.

Enhanced Microbial, Functional and Sensory Properties of Herbal Yogurt Fermented with Korean Traditional Plant Extracts

PubMed Central

Joung, Jae Yeon; Lee, Ji Young; Ha, Young Sik; Shin, Yong Kook; Kim, Younghoon; Kim, Sae Hun; Oh, Nam Su

2016-01-01

This study evaluated the effects of two Korean traditional plant extracts (Diospyros kaki THUNB. leaf; DK, and Nelumbo nucifera leaf; NN) on the fermentation, functional and sensory properties of herbal yogurts. Compared to control fermentation, all plant extracts increased acidification rate and reduced the time to complete fermentation (pH 4.5). Supplementation of plant extracts and storage time were found to influence the characteristics of the yogurts, contributing to increased viability of starter culture and phenolic compounds. In particular, the increase in the counts of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was highest (2.95 and 1.14 Log CFU/mL respectively) in DK yogurt. Furthermore, supplementation of the plant extracts significantly influenced to increase the antioxidant activity and water holding capacity and to produce volatile compounds. The higher antioxidant activity and water holding capacity were observed in NN yogurt than DK yogurt. Moreover, all of the sensory characteristics were altered by the addition of plant extracts. Addition of plant extracts increased the scores related to flavor, taste, and texture from plain yogurt without a plant extract, as a result of volatile compounds analysis. Thus, the overall preference was increased by plant extracts. Consequently, supplementation of DK and NN extracts in yogurt enhanced the antioxidant activity and physical property, moreover increased the acceptability of yogurt. These findings demonstrate the possibility of using plant extracts as a functional ingredient in the manufacture of herbal yogurt. PMID:27499669

Influence of galactooligosaccharides and modified waxy maize starch on some attributes of yogurt.

PubMed

Prasad, Laxmi N; Sherkat, Frank; Shah, Nagendra P

2013-01-01

This study examined the influence of galactooligosaccharides (GOS) and modified waxy maize starch (MWMS) addition on the growth of starter cultures, and syneresis and firmness of low-fat yogurt during storage for 28 d at 4 °C. The control yogurt (CY) was prepared without any prebiotics. Incorporation of 2.0% (w/v) GOS improved the growth of L. delbrueckii ssp. bulgaricus ATCC 11842 resulting in a shorter fermentation time. There was a significant (P < 0.05) increase in proteolysis in yogurt made with GOS (GOSY) as measured by absorbance value (0.728). Addition of GOS resulted in higher (P < 0.05) concentration of lactic and acetic acids in comparison with that of MWMSY and the CY up to day 14, thereafter, the product showed a decrease in lactic acid content in all 3 batches until the end of storage. The level of syneresis was the lowest (2.14%) in MWMSY as compared with that of GOSY (2.35%) and CY (2.53%). There was no statistically significant (P > 0.05) difference in the firmness among the 3 types of yogurt. © 2012 Institute of Food Technologists®

Physico-chemical, microstructural and rheological properties of camel-milk yogurt as enhanced by microbial transglutaminase.

PubMed

Abou-Soliman, Nagwa H I; Sakr, Sally S; Awad, Sameh

2017-05-01

Camel milk produces watery texture when it is processed to yogurt. Despite the extensive studies on microbial transglutaminase (MTGase) in dairy research, the effect of this enzyme on the properties of yogurt made from camel milk has not been studied. This study aims to investigate the impact of MTGase with and without bovine skimmed milk powder (SMP), whey protein concentrate (WPC),or β-lactoglobulin (β-lg) on physico-chemical, rheological, microstructural, and sensory properties of camel-milk yogurt during 15 days of storage period. MTGase treatment markedly reduced the fermentation time of unfortified and SMP-fortified camel milk. The fortification of camel milk without MTGase failed to give set-type yogurt. The treatment of unfortified milk with MTGase enormously improved the viscosity and the body of yogurt samples. Fortification of MTGase-treated milk impacted positively on the viscosity, the water holding capacity, and the density of the protein matrix in the gel microstructure, which were influenced by the type of dairy ingredients. All MTGase-treated yogurts differed from each other in hardness and adhesiveness values. Electrophoresis results showed that the susceptibility of the individual milk proteins to MTGase varied, and there were differences among the treatments toward the enzyme. SMP-fortified yogurt was the most accepted product. Generally, the addition of MTGase preparation at a concentration of 0.4%, simultaneously with starter culture, to fortified camel milk was considered an effective tool to solve the challenges of producing set-type yogurt from this milk.

Microstructural, textural, and sensory characteristics of probiotic yogurts fortified with sodium calcium caseinate or whey protein concentrate.

PubMed

Akalın, A S; Unal, G; Dinkci, N; Hayaloglu, A A

2012-07-01

The influence of milk protein-based ingredients on the textural characteristics, sensory properties, and microstructure of probiotic yogurt during a refrigerated storage period of 28 d was studied. Milk was fortified with 2% (wt/vol) skim milk powder as control, 2% (wt/vol) sodium calcium caseinate (SCaCN), 2% (wt/vol) whey protein concentrate (WPC) or a blend of 1% (wt/vol) SCaCN and 1% (wt/vol) WPC. A commercial yogurt starter culture and Bifidobacterium lactis Bb12 as probiotic bacteria were used for the production. The fortification with SCaCN improved the firmness and adhesiveness. Higher values of viscosity were also obtained in probiotic yogurts with SCaCN during storage. However, WPC enhanced water-holding capacity more than the caseinate. Addition of SCaCN resulted in a coarse, smooth, and more compact protein network; however, WPC gave finer and bunched structures in the scanning electron microscopy micrographs. The use of SCaCN decreased texture scores in probiotic yogurt; probably due to the lower water-holding capacity and higher syneresis values in the caseinate-added yogurt sample. Therefore, the textural characteristics of probiotic yogurts improved depending on the ingredient variety. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Microbial ecology and starter culture technology in coffee processing.

PubMed

Vinícius de Melo Pereira, Gilberto; Soccol, Vanete Thomaz; Brar, Satinder Kaur; Neto, Ensei; Soccol, Carlos Ricardo

2017-09-02

Coffee has been for decades the most commercialized food product and most widely consumed beverage in the world, with over 600 billion cups served per year. Before coffee cherries can be traded and processed into a final industrial product, they have to undergo postharvest processing on farms, which have a direct impact on the cost and quality of a coffee. Three different methods can be used for transforming the coffee cherries into beans, known as wet, dry, and semi-dry methods. In all these processing methods, a spontaneous fermentation is carried out in order to eliminate any mucilage still stuck to the beans and helps improve beverage flavor by microbial metabolites. The microorganisms responsible for the fermentation (e.g., yeasts and lactic acid bacteria) can play a number of roles, such as degradation of mucilage (pectinolytic activity), inhibition of mycotoxin-producing fungi growth, and production of flavor-active components. The use of starter cultures (mainly yeast strains) has emerged in recent years as a promising alternative to control the fermentation process and to promote quality development of coffee product. However, scarce information is still available about the effects of controlled starter cultures in coffee fermentation performance and bean quality, making it impossible to use this technology in actual field conditions. A broader knowledge about the ecology, biochemistry, and molecular biology could facilitate the understanding and application of starter cultures for coffee fermentation process. This review provides a comprehensive coverage of these issues, while pointing out new directions for exploiting starter cultures in coffee processing.

Evaluation of improved γ-aminobutyric acid production in yogurt using Lactobacillus plantarum NDC75017.

PubMed

Shan, Y; Man, C X; Han, X; Li, L; Guo, Y; Deng, Y; Li, T; Zhang, L W; Jiang, Y J

2015-04-01

Most γ-aminobutyric acid (GABA)-producing microorganisms are lactic acid bacteria (LAB), but the yield of GABA is limited in most of these GABA-producing strains. In this study, the production of GABA was carried out by using Lactobacillus plantarum NDC75017, a strain screened from traditional fermented dairy products in China. Concentrations of substrate (l-monosodium glutamate, L-MSG) and coenzyme (pyridoxal-5-phosphate, PLP) of glutamate decarboxylase (GAD) and culture temperature were investigated to evaluate their effects on GABA yield of Lb. plantarum NDC75017. The results indicated that GABA production was related to GAD activity and biomass of Lb. plantarum NDC75017. Response surface methodology was used to optimize conditions of GABA production. The optimal factors for GABA production were L-MSG at 80 mM, PLP at 18 μM, and a culture temperature of 36 °C. Under these conditions, production of GABA was maximized at 314.56 mg/100 g. Addition of Lb. plantarum NDC75017 to a commercial starter culture led to higher GABA production in fermented yogurt. Flavor and texture of the prepared yogurt and the control yogurt did not differ significantly. Thus, Lb. plantarum NDC75017 has good potential for manufacture of GABA-enriched fermented milk products. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Control of Biogenic Amines in Fermented Sausages: Role of Starter Cultures

PubMed Central

Latorre-Moratalla, M.L.; Bover-Cid, Sara; Veciana-Nogués, M.T.; Vidal-Carou, M.C.

2012-01-01

Biogenic amines show biological activity and exert undesirable physiological effects when absorbed at high concentrations. Biogenic amines are mainly formed by microbial decarboxylation of amino acids and thus are usually present in a wide range of foods, fermented sausages being one of the major biogenic amine sources. The use of selected starter cultures is one of the best technological measures to control aminogenesis during meat fermentation. Although with variable effectiveness, several works show the ability of some starters to render biogenic amine-free sausages. In this paper, the effect of different starter culture is reviewed and the factors determining their performance discussed. PMID:22586423

Evaluation of autochthonous micrococcus strains as starter cultures for the production of Kedong sufu.

PubMed

Feng, Z; Huang, S; Ai, Z W; Zhang, M; Zhai, S; Chen, X

2016-03-01

The technological properties of 22 micrococcus strains from traditional fermented Kedong sufu were evaluated in order to develop autochthonous starter cultures. The proteolytic, autolytic and lipolytic activity, salt tolerance, production and degradation of the biogenic amines of six Micrococcus luteus, nine Kocuria kristinae and seven Kocuria rosea were evaluated. The results indicated that these micrococcus strains exhibited a certain technological diversity, and the results also indicated the best properties to be used in mixed starter cultures. Based on the above findings, two sets of autochthonous starters were formulated. Considering the physicochemical properties and sensory characteristics of sufu, the maturation period of sufu was shortened by 30 days. The profiles of free amino acids and peptides partly revealed the mechanism of sensory quality and shorter ripening time of sufu manufactured using autochthonous mixed starters. Compared to back-slopping fermentation, sufu manufactured with selected autochthonous starter cultures exhibited lower levels of total biogenic amines. The selected strains could be used as starter to avoid the accumulation of high concentrations of biogenic amines while also maintaining typical sensory characteristics and preserving the autochthonous strains of the traditional Kedong sufu. The maturation times of Kedong sufu were shortened by 30 days with application of the autochthonous starter. Autochthonous mixed starters can reduce the generation of biogenic amines, speed up the sufu maturation process and preserve typical sensory quality. Furthermore, the rotation of two sets of mixed starter cultures can effectively resist phage attack during the production of sufu. © 2015 The Society for Applied Microbiology.

Whey protein concentrate and gum tragacanth as fat replacers in nonfat yogurt: chemical, physical, and microstructural properties.

PubMed

Aziznia, S; Khosrowshahi, A; Madadlou, A; Rahimi, J

2008-07-01

The effect of whey protein concentrate (WPC) and gum tragacanth (GT) as fat replacers on the chemical, physical, and microstructural properties of nonfat yogurt was investigated. The WPC (7.5, 15, and 20 g/L) and GT (0.25, 0.5, 0.75, and 1 g/L) were incorporated into the skim milk slowly at 40 to 45 degrees C with agitation. The yogurt mixes were pasteurized at 90 degrees C for 10 min, inoculated with 0.1% starter culture, and incubated at 42 degrees C to pH 4.6, then refrigerated overnight at 5 degrees C. A control nonfat yogurt and control full fat yogurt were prepared as described, but without addition of WPC and GT. Increasing amount of WPC led to the increase in total solids, total protein, acidity, and ash content, whereas GT did not affect chemical parameters. Increasing WPC caused a more compact structure consisting of robust casein particles and large aggregates. Firmness was increased and susceptibility to syneresis was decreased as WPC increased. No significant difference was observed for firmness and syneresis of yogurt fortified with GT up to 0.5 g/L compared with control nonfat yogurt. Increasing the amount of gum above 0.5 g/L produced softer gels with a greater tendency for syneresis than the ones prepared without it. Addition of GT led to the coarser and more open structure compared with control yogurt.

The effect of spices and manganese on meat starter culture activity.

PubMed

Coventry, M J; Hickey, M W

1993-01-01

Three species, two proprietary spice blends and six starter preparations used in commercial salami manufacture were analysed for manganese and magnesium content. A mettwurst spices blend showed the highest levels of manganese (0·77 ppm expressed as effective product level assuming a 1% spice content) while mild and hot paprika and milano blend contained levels of manganese 1 4 - 1 3 lower. Magnesium levels for spices ranged from 3·14 to 25·81 ppm. Only two of the six meat starter cultures showed high levels of manganese (7·77 and 16·12 ppm as effective product level based on inoculation rate) while magnesium levels for all starter cultures did not exceed 0·37 ppm. The pH of salami products made with starter cultures containing no added manganese lagged behind that of products made with added mangenese (5 ppm) by 0·2 pH units at 48 h. The effect of manganese ions on the fermentation rate of starter bacteria was studied further in a salami model system, in the absence and presence of added spices. The mettwurst blend produced greatest stimulation and the milano the least. A level of 1·2 ppm of added manganese was sufficient to achieve an optimal (< 4·9 pH units within 48 h) fermentation in the presence of all five spices tested in the salami model system. Copyright © 1993. Published by Elsevier Ltd.

Growth of probiotic bacteria and bifidobacteria in a soy yogurt formulation.

PubMed

Farnworth, E R; Mainville, I; Desjardins, M-P; Gardner, N; Fliss, I; Champagne, C

2007-05-01

Soy beverage and cows' milk yogurts were produced with Steptococcus thermophilus (ATCC 4356) and Lactobacillus delbrueckii subsp. bulgaricus (IM 025). The drop in pH during fermentation was faster in the soy beverage than in cows' milk, but the final pH values were similar. Yogurts were prepared with a yogurt starter in conjunction with either the probiotic bacteria Lactobacillus johnsonii NCC533 (La-1), Lactobacillus rhamnosus ATCC 53103 (GG) or human derived bifidobacteria. The presence of the probiotic bacteria did not affect the growth of the yogurt strains. Approximately 2 log increases in both L. rhamnosus GG and L. johnsonii La-1 were observed when each was added with the yogurt strains in both cows' milk and the soy beverage. Two of the five bifidobacteria strains grew well in the cows' milk and soy beverage during fermentation with the yogurt bacteria. High pressure liquid chromatography (HPLC) analyses showed that the probiotic bacteria and the bifidobacteria were using different sugars to support their growth, depending on whether the bacteria were growing in cows' milk or soy beverage.

Scarce Evidence of Yogurt Lactic Acid Bacteria in Human Feces after Daily Yogurt Consumption by Healthy Volunteers

PubMed Central

del Campo, Rosa; Bravo, Daniel; Cantón, Rafael; Ruiz-Garbajosa, Patricia; García-Albiach, Raimundo; Montesi-Libois, Alejandra; Yuste, Francisco-Javier; Abraira, Victor; Baquero, Fernando

2005-01-01

In a double-blind prospective study including 114 healthy young volunteers, the presence in human feces of the yogurt organisms Lactobacillus delbrueckii and Streptococcus thermophilus after repeated yogurt consumption (15 days) was analyzed by culture, specific PCR, and DNA hybridization of total fecal DNA. Detection of yogurt lactic acid bacteria in total fecal DNA by bacterial culture and PCR assay was consistently negative. DNA compatible with yogurt bacteria was found by hybridization experiments in only 10 (10.52%) of 96 individuals after consumption of fresh yogurt and in 2 (2.10%) of 96 individuals after consumption of pasteurized yogurt (P = 0.01). PMID:15640233

Behavior of Escherichia coli O157:H7 and Listeria monocytogenes during fermentation and storage of camel yogurt.

PubMed

Al-Nabulsi, Anas A; Olaimat, Amin N; Osaili, Tareq M; Ayyash, Mutamed M; Abushelaibi, Aisha; Jaradat, Ziad W; Shaker, Reyad; Al-Taani, Mahmoud; Holley, Richard A

2016-03-01

In addition to its nutritional and therapeutic properties, camel milk has the ability to suppress the growth of a wide range of foodborne pathogens, but there is a lack of information regarding the behavior of these pathogens in products such as yogurt produced from camel milk. The objective of the current study was to investigate the behavior of Listeria monocytogenes and Escherichia coli O157:H7 during manufacture and storage of camel yogurt. Camel milk inoculated with L. monocytogenes and E. coli O157:H7 was fermented at 43° C for 5h using freeze-dried lactic acid bacteria (LAB) starter cultures (Streptococcus thermophilus and Lactobacillus bulgaricus) and stored at 4 or 10 °C for 14 d. Camel milk inoculated with L. monocytogenes and E. coli O157:H7 without starter culture was also prepared. During fermentation, the numbers of L. monocytogenes and E. coli O157:H7 increased 0.3 and 1.6 log cfu/mL, respectively, in the presence of LAB, and by 0.3 and 2.7 log cfu/mL in the absence of LAB. During storage at 4 or 10 °C, L. monocytogenes increased 0.8 to 1.2 log cfu/mL by 14 d in camel milk without LAB, but in the presence of LAB, the numbers of L. monocytogenes were reduced by 1.2 to 1.7 log cfu/mL by 14 d. Further, E. coli O157:H7 numbers in camel milk were reduced by 3.4 to 3.5 log cfu/mL in the absence of LAB, but E. coli O157:H7 was not detected (6.3 log cfu/mL reduction) by 7d in camel yogurt made with LAB and stored at either temperature. Although camel milk contains high concentrations of natural antimicrobials, L. monocytogenes was able to tolerate these compounds in camel yogurt stored at refrigerator temperatures. Therefore, appropriate care should be taken during production of yogurt from camel milk to minimize the potential for postprocess contamination by this and other foodborne pathogens. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

NADH Oxidase of Streptococcus thermophilus 1131 is Required for the Effective Yogurt Fermentation with Lactobacillus delbrueckii subsp. bulgaricus 2038.

PubMed

Sasaki, Yasuko; Horiuchi, Hiroshi; Kawashima, Hiroko; Mukai, Takao; Yamamoto, Yuji

2014-01-01

We previously reported that dissolved oxygen (DO) suppresses yogurt fermentation with an industrial starter culture composed of Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) 2038 and Streptococcus thermophilus 1131, and also found that reducing the DO in the medium prior to fermentation (deoxygenated fermentation) shortens the fermentation time. In this study, we found that deoxygenated fermentation primarily increased the cell number of S. thermophilus 1131 rather than that of L. bulgaricus 2038, resulting in earlier l-lactate and formate accumulation. Measurement of the DO concentration and hydrogen peroxide generation in the milk medium suggested that DO is mainly removed by S. thermophilus 1131. The results using an H2O-forming NADH oxidase (Nox)-defective mutant of S. thermophilus 1131 revealed that Nox is the major oxygen-consuming enzyme of the bacterium. Yogurt fermentation with the S. thermophilus Δnox mutant and L. bulgaricus 2038 was significantly slower than with S. thermophilus 1131 and L. bulgaricus 2038, and the DO concentrations of the mixed culture did not decrease to less than 2 mg/kg within 3 hr. These observations suggest that Nox of S. thermophilus 1131 contributes greatly to yogurt fermentation, presumably by removing the DO in milk.

Whey-cheese production using freeze-dried kefir culture as a starter.

PubMed

Dimitrellou, D; Kourkoutas, Y; Banat, I M; Marchant, R; Koutinas, A A

2007-10-01

The aim of the present study was to evaluate the use of a freeze-dried kefir culture in the production of a novel type of whey-cheese similar to traditional Greek Myzithra-cheese, to achieve improvement of the quality characteristics of the final product and the extension of shelf-life. The use of kefir culture as a starter led to increased lactic acid concentrations and decreased pH values in the final product compared with whey-cheese without starter culture. The effect of the starter culture on production of aroma-related compounds responsible for cheese flavour was also studied using the solid phase microextraction gas chromatography/mass spectrometry technique. Spoilage in unsalted kefir-whey-cheese was observed on the thirteenth and the twentieth day of preservation at 10 and 5 degrees C, respectively, while the corresponding times for unsalted whey-cheese preservation were 11 and 14 days. The cheeses produced were characterized as high-quality products during the preliminary sensory evaluation. An indication of increased preservation time was attributed to the freeze-dried kefir culture, which also seemed to suppress growth of pathogens. The results suggested the use of kefir culture as a means to extend the shelf-life of dairy products with reduced or no salt content.

Sensory quality of Camembert-type cheese: Relationship between starter cultures and ripening molds.

PubMed

Galli, Bruno Domingues; Martin, José Guilherme Prado; da Silva, Paula Porrelli Moreira; Porto, Ernani; Spoto, Marta Helena Fillet

2016-10-03

Starter cultures and ripening molds used in the manufacture of moldy cheese aimed at obtaining characteristic flavors and textures considerably differ among dairy industries. Thus, the study of variables inherent to the process and their influence on sensory patterns in cheese can improve the standardization and control of the production process. The aim of this work was to study the influence of three different variables on the sensory quality of Camembert-type cheese: type of lactic bacteria, type of ripener molds and inoculation method. Batches of Camembert-type cheese were produced using O or DL-type mesophilic starter culture, ripened with Penicillium camemberti or Penicillium candidum and mold inoculation was made directly into the milk or by spraying. All batches were sensorially evaluated using Quantitative Descriptive Analysis (QDA) with panelists trained for various attributes. Among the combinations analyzed, those resulting in more typical Camembert-type cheese were those using O-type mesophilic starter culture and P. candidum maturation mold directly applied into the milk or sprayed and those using DL-type mesophilic starter and P. camemberti ripener mold applied by surface spraying. These results demonstrate, therefore, that the combination of different ripener molds, inoculation methods and starter cultures directly influences the sensory quality of Camembert-type cheese, modifying significantly its texture, appearance, aroma and taste. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of inoculation of commercial starter cultures on the quality and histamine accumulation in fermented sausages.

PubMed

Wang, Xinhui; Ren, Hongyang; Wang, Wei; Zhang, Yin; Bai, Ting; Li, Junxia; Zhu, Wenyou

2015-02-01

To meet the requirements of high-quality safe products, starter cultures are used to produce fermented sausages. The effects of 3 commercial starter cultures, namely SM-194, T-SPX, and SM-181, on histamine accumulation and quality parameters including microbial quality, pH, water activity, and total volatile base nitrogen, as well as the color and texture properties, were evaluated during the fermentation and ripening of fermented sausages. Although initial counts of Escherichia coli, Enterobacteriaceae, and Pseudomonas were similar in the 4 batches, the growth of these microorganisms was significantly inhibited (P < 0.05) in batches SM-194, T-SPX, and SM-181 throughout the fermentation and ripening period. The counts of E. coli, Enterobacteriaceae, and Pseudomonas increased to maximum levels of 3.89, 4.41, and 5.15 log10 colony forming units/g in the control sausages, respectively. At the end of ripening, the levels of histamine were 8.85, 0.32, 7.82, and 3.18 mg/kg for batches C, SM-194, T-SPX, and SM-181, respectively. The results revealed that commercial starter cultures, particularly starter cultures SM-194 and SM-181, made a great contribution to histamine reduction. In addition, batches inoculated with starter cultures showed a stronger acidification and lower level of total volatile base nitrogen than the control sample during production (P < 0.05). In conclusion, it seems that the inoculation of commercial starter cultures, particularly starter cultures SM-194 and SM-181, contributes to improving microbial quality, hygienic quality and food safety of fermented sausages. © 2015 Institute of Food Technologists®

Lactococcus lactis Diversity in Undefined Mixed Dairy Starter Cultures as Revealed by Comparative Genome Analyses and Targeted Amplicon Sequencing of epsD.

PubMed

Frantzen, Cyril A; Kleppen, Hans Petter; Holo, Helge

2018-02-01

Undefined mesophilic mixed (DL) starter cultures are used in the production of continental cheeses and contain unknown strain mixtures of Lactococcus lactis and leuconostocs. The choice of starter culture affects the taste, aroma, and quality of the final product. To gain insight into the diversity of Lactococcus lactis strains in starter cultures, we whole-genome sequenced 95 isolates from three different starter cultures. Pan-genomic analyses, which included 30 publically available complete genomes, grouped the strains into 21 L. lactis subsp . lactis and 28 L. lactis subsp. cremoris lineages. Only one of the 95 isolates grouped with previously sequenced strains, and the three starter cultures showed no overlap in lineage distributions. The culture diversity was assessed by targeted amplicon sequencing using purR , a core gene, and epsD , present in 93 of the 95 starter culture isolates but absent in most of the reference strains. This enabled an unprecedented discrimination of starter culture Lactococcus lactis and revealed substantial differences between the three starter cultures and compositional shifts during the cultivation of cultures in milk. IMPORTANCE In contemporary cheese production, standardized frozen seed stock starter cultures are used to ensure production stability, reproducibility, and quality control of the product. The dairy industry experiences significant disruptions of cheese production due to phage attacks, and one commonly used countermeasure to phage attack is to employ a starter rotation strategy, in which two or more starters with minimal overlap in phage sensitivity are used alternately. A culture-independent analysis of the lactococcal diversity in complex undefined starter cultures revealed large differences between the three starter cultures and temporal shifts in lactococcal composition during the production of bulk starters. A better understanding of the lactococcal diversity in starter cultures will enable the development of

Safety improvement and preservation of typical sensory qualities of traditional dry fermented sausages using autochthonous starter cultures.

PubMed

Talon, Régine; Leroy, Sabine; Lebert, Isabelle; Giammarinaro, Philippe; Chacornac, Jean-Paul; Latorre-Moratalla, Mariluz; Vidal-Carou, Carmen; Zanardi, Emanuela; Conter, Mauro; Lebecque, Annick

2008-08-15

Traditional dry fermented sausages are manufactured without addition of starter cultures in small-scale processing units, their fermentation relying on indigenous microflora. Characterisation and control of these specific bacteria are essential for the sensory quality and the safety of the sausages. The aim of this study was to develop an autochthonous starter culture that improves safety while preserving the typical sensory characteristics of traditional sausages. An autochthonous starter composed of Lactobacillus sakei, Staphylococcus equorum and Staphylococcus succinus isolated from a traditional fermented sausage was developed. These strains were tested for their susceptibility to antibiotics and their production of biogenic amines. This starter was evaluated in situ at the French traditional processing unit where the strains had been isolated. Effects of the autochthonous starter were assessed by analysing the microbial, physico-chemical, biochemical and sensory characteristics of the sausages. Inoculation with the chosen species was confirmed using known species-specific PCR assays for L. sakei and S. equorum and a species-specific PCR assay developed in this study for S. succinus. Strains were monitored by pulse-field gel electrophoresis typing. Addition of autochthonous microbial starter cultures improved safety compared with the traditional natural fermentation of sausages, by inhibiting the pathogen Listeria monocytogenes, decreasing the level of biogenic amines and by limiting fatty acid and cholesterol oxidation. Moreover, autochthonous starter did not affect the typical sensory quality of the traditional sausages. This is the first time to our knowledge that selection, development and validation in situ of autochthonous starter cultures have been carried out, and also the first time that S. equorum together with S. succinus have been used as starter cultures for meat fermentation. Use of autochthonous starter cultures is an effective tool for limiting

Antimicrobial susceptibility of starter culture bacteria used in Norwegian dairy products.

PubMed

Katla, A K; Kruse, H; Johnsen, G; Herikstad, H

2001-07-20

Commercial starter culture bacteria are widely used in the production of dairy products and could represent a potential source for spread of genes encoding resistance to antimicrobial agents. To learn more about the antimicrobial susceptibility of starter culture bacteria used in Norwegian dairy products, a total of 189 isolates of lactic acid bacteria were examined for susceptibility to ampicillin, penicillin G, cephalothin, vancomycin, bacitracin, gentamicin, streptomycin, erythromycin, tetracycline, chloramphenicol, quinupristin/dalfopristin, ciprofloxacin, trimethoprim and sulphadiazine using Etest for MIC determination. Most of the isolates (140) originated from 39 dairy products (yoghurt, sour cream, fermented milk and cheese), while 49 were isolated directly from nine commercial cultures. The bacteria belonged to the genera Lactobacillus, Lactococcus, Leuconostoc and Streptococcus. Only one of the 189 isolates was classified as resistant to an antimicrobial agent included in the study. This isolate, a lactobacillus, was classified as high level resistant to streptomycin. The remaining isolates were not classified as resistant to the antimicrobial agents included other than to those they are known to have a natural reduced susceptibility to. Thus, starter culture bacteria in Norwegian dairy products do not seem to represent a source for spread of genes encoding resistance to antimicrobial agents.

Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

PubMed

Abdelazez, Amro; Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao; Abdelmotaal, Heba; Sami, Rokayya; Meng, Xiang-Chen

2017-01-01

Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. ( Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture ( Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at -18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only.

Breeding Strategy To Generate Robust Yeast Starter Cultures for Cocoa Pulp Fermentations

PubMed Central

Meersman, Esther; Steensels, Jan; Paulus, Tinneke; Struyf, Nore; Saels, Veerle; Mathawan, Melissa; Koffi, Jean; Vrancken, Gino

2015-01-01

Cocoa pulp fermentation is a spontaneous process during which the natural microbiota present at cocoa farms is allowed to ferment the pulp surrounding cocoa beans. Because such spontaneous fermentations are inconsistent and contribute to product variability, there is growing interest in a microbial starter culture that could be used to inoculate cocoa pulp fermentations. Previous studies have revealed that many different fungi are recovered from different batches of spontaneous cocoa pulp fermentations, whereas the variation in the prokaryotic microbiome is much more limited. In this study, therefore, we aimed to develop a suitable yeast starter culture that is able to outcompete wild contaminants and consistently produce high-quality chocolate. Starting from specifically selected Saccharomyces cerevisiae strains, we developed robust hybrids with characteristics that allow them to efficiently ferment cocoa pulp, including improved temperature tolerance and fermentation capacity. We conducted several laboratory and field trials to show that these new hybrids often outperform their parental strains and are able to dominate spontaneous pilot scale fermentations, which results in much more consistent microbial profiles. Moreover, analysis of the resulting chocolate showed that some of the cocoa batches that were fermented with specific starter cultures yielded superior chocolate. Taken together, these results describe the development of robust yeast starter cultures for cocoa pulp fermentations that can contribute to improving the consistency and quality of commercial chocolate production. PMID:26150457

Antiproliferative effects of yogurt fractions obtained by membrane dialysis on cultured mammalian intestinal cells.

PubMed

Ganjam, L S; Thornton, W H; Marshall, R T; MacDonald, R S

1997-10-01

The consumption of yogurt has been associated with a reduced incidence of colon cancer in population groups. Bioactive peptides produced during bacterial fermentation may alter the risk of colon cancer via modification of cell proliferation in the colon. Using our previously described cell culture model system, we have isolated a yogurt fraction that decreases cell proliferation. Yogurt was fractionated using 10,000- and 500-Da membrane dialysis. When the yogurt fraction was incubated with IEC-6 or Caco-2 cells, cell division was decreased compared with control treatments, as determined by thymidine incorporation. Cell division was not inhibited in response to a similarly produced milk fraction or in response to solutions of lactic acid. The determination of cell kinetics by flow cytometry revealed a decrease in the number of cells in the initial growth phase in response to the yogurt fraction for the IEC-6 cells, but not the Caco-2 cells. Alpha-Lactalbumin inhibited cell division of both cell lines, but beta-casein did not.

Use of autochthonous Pediococcus acidilactici and Staphylococcus vitulus starter cultures in the production of "chorizo" in 2 different traditional industries.

PubMed

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

2012-01-01

The present study determined how the different ripening conditions affected the growth and development of 3 autochthonous starter cultures, and the physico-chemical and sensory characteristics of chorizo. Each of 3 strains of Pediococcus acidilactici (MC184, MS198, and MS200) and one of Staphylococcus vitulus (RS34) were associated to prepare the starter cultures, P184S34, P198S34, and P200S34. Then, chorizo was prepared following 2 manufacturing procedures. The autochthonous starter cultures were able to compete and colonize the sausages in both ripening procedures. The use of the starter cultures showed evident differences by the texture analysis, with the control batches being generally tougher than the starter culture batches. Also, the highest biogenic amine (BA) levels were found in control batches and the lowest in P200S34 batches. While the use of these starter cultures does not change the sensory characteristics of these traditional fermented sausages, it improves their homogeneity and safety, except for P184S34 batch in which more BAs are detected in industry 2. The 3 autochthonous starter cultures selected could be used in traditional industries because they are able to compete well and colonize the dry fermented sausages "chorizo." The use of these starter cultures improves the texture and homogeneity of traditional fermented sausages. Biogenic amines decreased in the starter cultures batches improving the safety. © 2011 Institute of Food Technologists®

Production of a Functional Frozen Yogurt Fortified with Bifidobacterium spp.

PubMed Central

Muhammad, Zafarullah; Zhang, Qiu-Xue; Zhu, Zong-Tao

2017-01-01

Frozen dairy products have characteristics of both yogurt and ice cream and could be the persuasive carriers of probiotics. Functions of the frozen yogurt containing viable bifidobacterial cells are recognized and favored by the people of all ages. We developed a kind of yogurt supplemented by Bifidobacterium species. Firstly, five strains of Bifidobacterium spp. (Bifidobacterium bifidum ATCC 11547, Bifidobacterium longum ATCC 11549, Bifidobacterium infantis ATCC 11551, Bifidobacterium adolescentis ATCC 11550, and Bifidobacterium breve ATCC 11548) were evaluated based on the feasibility criteria of probiotics, comprising acid production, bile tolerance, and adhesion to epithelial cells. Formerly, we combined the optimum strains with yogurt culture (Lactobacillus delbrueckii subsp. bulgaricus EMCC 11102 and Streptococcus salivarius subsp. thermophilus EMCC 11044) for producing frozen yogurt. Finally, physiochemical properties and sensory evaluation of the frozen yogurt were investigated during storage of 60 days at −18°C. Results directed that Bifidobacterium adolescentis ATCC 11550 and Bifidobacterium infantis ATCC 11551 could be utilized with yogurt culture for producing frozen yogurt. Moreover, the frozen yogurt fermented by two bifidobacterial strains and yogurt culture gained the high evaluation in the physiochemical properties and sensory evaluation. In summary, our results revealed that there was no significant difference between frozen yogurt fermented by Bifidobacterium spp. and yogurt culture and that fermented by yogurt culture only. PMID:28691028

Inoculation of starter cultures in a semi-dry coffee (Coffea arabica) fermentation process.

PubMed

Evangelista, Suzana Reis; Miguel, Maria Gabriela da Cruz Pedrozo; Cordeiro, Cecília de Souza; Silva, Cristina Ferreira; Pinheiro, Ana Carla Marques; Schwan, Rosane Freitas

2014-12-01

The aim of this study was to evaluate the use of yeasts as starter cultures in coffee semi-dry processing. Arabica coffee was inoculated with one of the following starter cultures: Saccharomyces cerevisiae UFLA YCN727, S. cerevisiae UFLA YCN724, Candida parapsilosis UFLA YCN448 and Pichia guilliermondii UFLA YCN731. The control was not inoculated with a starter culture. Denaturing gradient gel electrophoresis (DGGE) was used to assess the microbial population, and organic acids and volatile compounds were quantified by HPLC and HS-SPME/GC, respectively. Sensory analyses were evaluated using the Temporal Dominance of Sensations (TDS). DGGE analysis showed that the inoculated yeasts were present throughout the fermentation. Other yeast species were also detected, including Debaryomyces hansenii, Cystofilobasidium ferigula and Trichosporon cavernicola. The bacterial population was diverse and was composed of the following genera: Weissella, Leuconostoc, Gluconobacter, Pseudomonas, Pantoea, Erwinia and Klebsiella. Butyric and propionic acids, were not detected in any treatment A total of 47 different volatiles compounds have been identified. The coffee inoculated with yeast had a caramel flavor that was not detected in the control, as assessed by TDS. The use of starter cultures during coffee fermentation is an interesting alternative for obtaining a beverage quality with distinctive flavor. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparative evaluation of yogurt and low-fat cheddar cheese as delivery media for probiotic Lactobacillus casei.

PubMed

Sharp, M D; McMahon, D J; Broadbent, J R

2008-09-01

This study used Lactobacillus casei 334e, an erythromycin-resistant derivative of ATCC 334, as a model to evaluate viability and acid resistance of probiotic L. casei in low-fat Cheddar cheese and yogurt. Cheese and yogurt were made by standard methods and the probiotic L. casei adjunct was added at approximately 10(7) CFU/g with the starter cultures. Low-fat cheese and yogurt samples were stored at 8 and 2 degrees C, respectively, and numbers of the L. casei adjunct were periodically determined by plating on MRS agar that contained 5 microg/mL of erythromycin. L. casei 334e counts in cheese and yogurt remained at 10(7) CFU/g over 3 mo and 3 wk, respectively, indicating good survival in both products. Acid challenge studies in 8.7 mM phosphoric acid (pH 2) at 37 degrees C showed numbers of L. casei 334e in yogurt dropped from 10(7) CFU/g to less than 10(1) CFU/g after 30 min, while counts in cheese samples dropped from 10(7) CFU/g to about 10(5) after 30 min, and remained near 10(4) CFU/g after 120 min. As a whole, these data showed that low-fat Cheddar cheese is a viable delivery food for probiotic L. casei because it allowed for good survival during storage and helped protect cells against the very low pH that will be encountered during stomach transit.

Breeding Strategy To Generate Robust Yeast Starter Cultures for Cocoa Pulp Fermentations.

PubMed

Meersman, Esther; Steensels, Jan; Paulus, Tinneke; Struyf, Nore; Saels, Veerle; Mathawan, Melissa; Koffi, Jean; Vrancken, Gino; Verstrepen, Kevin J

2015-09-01

Cocoa pulp fermentation is a spontaneous process during which the natural microbiota present at cocoa farms is allowed to ferment the pulp surrounding cocoa beans. Because such spontaneous fermentations are inconsistent and contribute to product variability, there is growing interest in a microbial starter culture that could be used to inoculate cocoa pulp fermentations. Previous studies have revealed that many different fungi are recovered from different batches of spontaneous cocoa pulp fermentations, whereas the variation in the prokaryotic microbiome is much more limited. In this study, therefore, we aimed to develop a suitable yeast starter culture that is able to outcompete wild contaminants and consistently produce high-quality chocolate. Starting from specifically selected Saccharomyces cerevisiae strains, we developed robust hybrids with characteristics that allow them to efficiently ferment cocoa pulp, including improved temperature tolerance and fermentation capacity. We conducted several laboratory and field trials to show that these new hybrids often outperform their parental strains and are able to dominate spontaneous pilot scale fermentations, which results in much more consistent microbial profiles. Moreover, analysis of the resulting chocolate showed that some of the cocoa batches that were fermented with specific starter cultures yielded superior chocolate. Taken together, these results describe the development of robust yeast starter cultures for cocoa pulp fermentations that can contribute to improving the consistency and quality of commercial chocolate production. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

NADH Oxidase of Streptococcus thermophilus 1131 is Required for the Effective Yogurt Fermentation with Lactobacillus delbrueckii subsp. bulgaricus 2038

PubMed Central

SASAKI, Yasuko; HORIUCHI, Hiroshi; KAWASHIMA, Hiroko; MUKAI, Takao; YAMAMOTO, Yuji

2014-01-01

We previously reported that dissolved oxygen (DO) suppresses yogurt fermentation with an industrial starter culture composed of Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) 2038 and Streptococcus thermophilus 1131, and also found that reducing the DO in the medium prior to fermentation (deoxygenated fermentation) shortens the fermentation time. In this study, we found that deoxygenated fermentation primarily increased the cell number of S. thermophilus 1131 rather than that of L. bulgaricus 2038, resulting in earlier l-lactate and formate accumulation. Measurement of the DO concentration and hydrogen peroxide generation in the milk medium suggested that DO is mainly removed by S. thermophilus 1131. The results using an H2O-forming NADH oxidase (Nox)-defective mutant of S. thermophilus 1131 revealed that Nox is the major oxygen-consuming enzyme of the bacterium. Yogurt fermentation with the S. thermophilus Δnox mutant and L. bulgaricus 2038 was significantly slower than with S. thermophilus 1131 and L. bulgaricus 2038, and the DO concentrations of the mixed culture did not decrease to less than 2 mg/kg within 3 hr. These observations suggest that Nox of S. thermophilus 1131 contributes greatly to yogurt fermentation, presumably by removing the DO in milk. PMID:24936380

Identification of potential probiotic starter cultures for Scandinavian-type fermented sausages.

PubMed

Klingberg, Trine Danø; Axelsson, Lars; Naterstad, Kristine; Elsser, Dieter; Budde, Birgitte Bjørn

2005-12-15

Potential probiotic cultures suitable as starter cultures for the Scandinavian-type fermented sausages were identified among strains well-adapted to fermented meats as well as strains originating from a culture collection. From 15 different fermented meat products, 22 strains were isolated as dominant non-starter lactic acid bacteria (NSLAB). The isolates were identified by RAPD, API and sequence analysis of 16S rRNA and showed to be five strains of Lactobacillus sakei, five strains of Lactobacillus farciminis, five strains belonging to the group of Lactobacillus plantarum/pentosus, four strains of Lactobacillus alimentarius, two strains of Lactobacillus brevis and one strain of Lactobacillus versmoldensis. Heterofermentative strains as well as strains not growing at 37 degrees C and not lowering pH below 5.1 in a meat model were excluded leaving 9 strains for further studies. These strains together with 19 strains from a culture collection were evaluated by in vitro methods including survival upon exposure to pH 2.5 or 0.3% oxgall and adhesion to the human colon adenocarcinoma cell line Caco-2 as well as antimicrobial activity against potential pathogens. Strains that fulfilled all the probiotic criteria and showed to be fast acid producers in a meat model included three strains belonging to the group of Lb. plantarum/pentosus (MF1291, MF1298, MF1300) which originated from the dominant NSLAB of fermented meat products. MF1291 and MF 1298 were further identified as Lb. plantarum and MF1300 as Lb. pentosus. The three strains were all successfully applied as starter cultures for the production of fermented sausage. The viable count at the end of the processing period reached high cell numbers (4.7x10(7)-2.9x10(8) cfu/g) and pH of the sausages decreased to pH 4.8-4.9 without any flavour deviation compared to sausage fermented by a commercial meat starter culture.

Chromosomal Diversity in Lactococcus lactis and the Origin of Dairy Starter Cultures

PubMed Central

Kelly, William J.; Ward, Lawrence J. H.; Leahy, Sinead C.

2010-01-01

A large collection of Lactococcus lactis strains, including wild-type isolates and dairy starter cultures, were screened on the basis of their phenotype and the macrorestriction patterns produced from pulsed-field gel electrophoresis (PFGE) analysis of SmaI digests of genomic DNA. Three groups of dairy starter cultures, used for different purposes in the dairy industry, and a fourth group made up of strains isolated from the environment were selected for analysis of their chromosomal diversity using the endonuclease I-CeuI. Chromosome architecture was largely conserved with each strain having six copies of the rRNA genes, and the chromosome size of individual strains ranged between 2,240 and 2,688 kb. The origin of L. lactis strains showed the greatest correlation with chromosome size, and dairy strains, particularly those with the cremoris phenotype, had smaller chromosomes than wild-type strains. Overall, this study, coupled with analysis of the sequenced L. lactis genomes, provides evidence that defined strain dairy starter cultures have arisen from plant L. lactis strains. Adaptation of these strains to the dairy environment has involved loss of functions resulting in smaller chromosomes and acquisition of genes (usually plasmid associated) that facilitate growth in milk. We conclude that dairy starter cultures generally and the industrially used cremoris and diacetylactis phenotype strains in particular comprise a specialized group of L. lactis strains that have been selected to become an essential component of industrial processes and have evolved accordingly, so that they are no longer fit to survive outside the dairy environment. PMID:20847124

Acetic acid bacteria in traditional balsamic vinegar: phenotypic traits relevant for starter cultures selection.

PubMed

Gullo, Maria; Giudici, Paolo

2008-06-30

This review focuses on acetic acid bacteria in traditional balsamic vinegar process. Although several studies are available on acetic acid bacteria ecology, metabolism and nutritional requirements, their activity as well as their technological traits in homemade vinegars as traditional balsamic vinegar is not well known. The basic technology to oxidise cooked grape must to produce traditional balsamic vinegar is performed by the so called "seed-vinegar" that is a microbiologically undefined starter culture obtained from spontaneous acetification of previous raw material. Selected starter cultures are the main technological improvement in order to innovate traditional balsamic vinegar production but until now they are rarely applied. To develop acetic acid bacteria starter cultures, selection criteria have to take in account composition of raw material, acetic acid bacteria metabolic activities, applied technology and desired characteristics of the final product. For traditional balsamic vinegar, significative phenotypical traits of acetic acid bacteria have been highlighted. Basic traits are: ethanol preferred and efficient oxidation, fast rate of acetic acid production, tolerance to high concentration of acetic acid, no overoxidation and low pH resistance. Specific traits are tolerance to high sugar concentration and to a wide temperature range. Gluconacetobacter europaeus and Acetobacter malorum strains can be evaluated to develop selected starter cultures since they show one or more suitable characters.

Quantitative analysis of the lactic acid and acetaldehyde produced by Streptococcus thermophilus and Lactobacillus bulgaricus strains isolated from traditional Turkish yogurts using HPLC.

PubMed

Gezginc, Y; Topcal, F; Comertpay, S; Akyol, I

2015-03-01

The present study was conducted to evaluate the lactic acid- and acetaldehyde-producing abilities of lactic acid bacterial species isolated from traditionally manufactured Turkish yogurts using HPLC. The lactic acid bacterial species purified from the yogurts were the 2 most widely used species in industrial yogurt production: Streptococcus thermophilus and Lactobacillus bulgaricus. These bacteria have the ability to ferment hexose sugars homofermentatively to generate lactic acid and some carbonyl compounds, such as acetaldehyde through pyruvate metabolism. The levels of the compounds produced during fermentation influence the texture and the flavor of the yogurt and are themselves influenced by the chemical composition of the milk, processing conditions, and the metabolic activity of the starter culture. In the study, morphological, biochemical, and molecular characteristics were employed to identify the bacteria obtained from homemade yogurts produced in different regions of Turkey. A collection of 91 Strep. thermophilus and 35 L. bulgaricus strains were investigated for their lactic acid- and acetaldehyde-formation capabilities in various media such as cow milk, LM17 agar, and aerobic-anaerobic SM17 agar or de Man, Rogosa, and Sharpe agar. The amounts of the metabolites generated by each strain in all conditions were quantified by HPLC. The levels were found to vary depending on the species, the strain, and the growth conditions used. Whereas lactic acid production ranged between 0 and 77.9 mg/kg for Strep. thermophilus strains, it ranged from 0 to 103.5 mg/kg for L. bulgaricus. Correspondingly, the ability to generate acetaldehyde ranged from 0 to 105.9 mg/kg in Strep. thermophilus and from 0 to 126.9 mg/kg in L. bulgaricus. Our study constitutes the first attempt to determine characteristics of the wild strains isolated from traditional Turkish yogurts, and the approach presented here, which reveals the differences in metabolite production abilities of the

Table Olive Fermentation Using Starter Cultures with Multifunctional Potential

PubMed Central

Bonatsou, Stamatoula; Tassou, Chrysoula C.; Panagou, Efstathios Z.; Nychas, George-John E.

2017-01-01

Table olives are one of the most popular plant-derived fermented products. Their enhanced nutritional value due to the presence of phenolic compounds and monounsaturated fatty acids makes olives an important food commodity of the Mediterranean diet. However, despite its economic significance, table olive fermentation is mainly craft-based and empirically driven by the autochthonous microbiota of the olives depending on various intrinsic and extrinsic factors, leading to a spontaneous process and a final product of variable quality. The use of microorganisms previously isolated from olive fermentations and studied for their probiotic potential and technological characteristics as starter cultures may contribute to the reduction of spoilage risk resulting in a controlled fermentation process. This review focuses on the importance of the development and implementation of multifunctional starter cultures related to olives with desirable probiotic and technological characteristics for possible application on table olive fermentation with the main purpose being the production of a health promoting and sensory improved functional food. PMID:28555038

Table Olive Fermentation Using Starter Cultures with Multifunctional Potential.

PubMed

Bonatsou, Stamatoula; Tassou, Chrysoula C; Panagou, Efstathios Z; Nychas, George-John E

2017-05-28

Table olives are one of the most popular plant-derived fermented products. Their enhanced nutritional value due to the presence of phenolic compounds and monounsaturated fatty acids makes olives an important food commodity of the Mediterranean diet. However, despite its economic significance, table olive fermentation is mainly craft-based and empirically driven by the autochthonous microbiota of the olives depending on various intrinsic and extrinsic factors, leading to a spontaneous process and a final product of variable quality. The use of microorganisms previously isolated from olive fermentations and studied for their probiotic potential and technological characteristics as starter cultures may contribute to the reduction of spoilage risk resulting in a controlled fermentation process. This review focuses on the importance of the development and implementation of multifunctional starter cultures related to olives with desirable probiotic and technological characteristics for possible application on table olive fermentation with the main purpose being the production of a health promoting and sensory improved functional food.

Classification of Swiss cheese starter and adjunct cultures using Fourier transform infrared microspectroscopy.

PubMed

Prabhakar, V; Kocaoglu-Vurma, N; Harper, J; Rodriguez-Saona, L

2011-09-01

The acceptability of Swiss cheese largely depends on the flavor profile, and strain variations of cheese cultures will affect the final quality. Conventional biochemical methods to identify the cultures at the strain level are time-consuming and expensive, and require skilled labor. Our objective was to develop rapid classification methods of starter cultures at the strain level by using a combination of hydrophobic grid membrane filters and Fourier transform infrared (FTIR) spectroscopy. Forty-four pulsed-field gel electrophoresis-verified strains of starter and nonstarter cultures including Streptococcus thermophilus, Propionibacterium freudenreichii, and Lactobacillus spp. were analyzed. The strains were grown on their respective agar media, transferred to broth media, and incubated. Then, cultures were centrifuged and the pellets were resuspended in saline solution (10 μL). Aliquots (2 μL) of the suspended bacterial solution were placed onto a grid of the hydrophobic grid membrane filters, having 6 grids per each strain analyzed. The dried filters were read by FTIR microspectroscopy fitted with an attenuated total reflectance probe. Collected spectra were statistically analyzed by a soft independent modeling of class analogy (SIMCA) for pattern recognition. Classification models were developed for Streptococcus thermophilus, Propionibacterium freudenreichii, and Lactobacillus spp. strains. The models showed major discrimination in the spectral region from 1,200 to 900 cm(-1) associated with signals from phosphate-containing compounds and various polysaccharides in the cell wall. The developed method allowed for rapid classification of several Swiss cheese starter and nonstarter cultures at the strain level. This information provides a detailed overview of microbiological status, which would enable corrective measures to be taken early in the cheese making process, limiting production of inferior quality cheese and minimizing defects. This method could be an

Residue behavior of organochlorine pesticides during the production process of yogurt and cheese.

PubMed

Duan, Jing; Cheng, Zheng; Bi, Jiawei; Xu, Yangguang

2018-04-15

The presence of organochlorine pesticides (OCPs) in dairy products can lead to human exposure. This study investigated the behavior of OCP residues in milk during yogurt and cheese production. Gas chromatography with electron-capture detection (GC-ECD) was used to detect α-hexachlorocyclohexane (HCH), hexachlorobenzene (HCB), γ-HCH, g-chlordane, and α-chlordane in fresh milk, yogurt, and cheese. The results showed that fermentation reduced the residual concentration of OCPs in yogurt, with processing factors (PFs) ranging from 0.42 to 0.64. The reductions in residue levels during fermentation were due to the activity of the starter. The cheese making process increased the residual concentration of OCPs in cheese compared to raw milk, with PFs ranging from 2.37 to 4.93. Additionally, milk, yogurt, and cheese samples were purchased from local markets and OCP levels were analyzed. The target OCPs ranged from ND to 16.50 μg/kg in these samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Survival of Escherichia coli O157:H7, Listeria monocytogenes 4b and Yersinia enterocolitica O3 in different yogurt and kefir combinations as prefermentation contaminant.

PubMed

Gulmez, M; Guven, A

2003-01-01

To compare microbiological safety of yogurt, kefir and different combinations of yogurt and kefir samples by using three foodborne pathogenic strains (Escherichia coli O157:H7, Listeria monocytogenes 4b and Yersinia enterocolitica O3) as indicators. Fresh yogurt and kefir drinks were added to pasteurized milk at a 5% rate either separately or together, and then incubated at different temperatures (43 degrees C for yogurt and 30 degrees C for kefir), depending on appropriate growth temperature of their starter microflora. While traditional yogurt was found to be the least suppressive on the three pathogenic micro-organisms, samples obtained from two subsequent fermentation process (samples fermented at 43 degrees C for 3 h and at 30 degrees C for 21 h) were more suppressive than that of traditional kefir. There was no significant survival difference between E. coli O157:H7 and L. monocytogenes 4b in samples tested (P > 0.05), but Y. enterocolitica O3 was more susceptible than other two test strains (P < 0.05). The microbiological safety of the dairy product fermented at two consecutive periods was superior than that of traditional yogurt or kefir alone. These experiments may mimic what happens when yogurt and kefir starter micro-organisms are combined in a milk fermentation process with different time and temperature periods.

Evaluation of the use of malic acid decarboxylase-deficient starter culture in NaCl-free cucumber fermentations to reduce bloater incidence.

PubMed

Zhai, Y; Pérez-Díaz, I M; Diaz, J T; Lombardi, R L; Connelly, L E

2018-01-01

Accumulation of carbon dioxide (CO 2 ) in cucumber fermentations is known to cause hollow cavities inside whole fruits or bloaters, conducive to economic losses for the pickling industry. This study focused on evaluating the use of a malic acid decarboxylase (MDC)-deficient starter culture to minimize CO 2 production and the resulting bloater index in sodium chloride-free cucumber fermentations brined with CaCl 2 . Attempts to isolate autochthonous MDC-deficient starter cultures from commercial fermentations, using the MD medium for screening, were unsuccessful. The utilization of allochthonous MDC-deficient starter cultures resulted in incomplete utilization of sugars and delayed fermentations. Acidified fermentations were considered, to suppress the indigenous microbiota and favour proliferation of the allochthonous MDC-deficient Lactobacillus plantarum starter cultures. Inoculation of acidified fermentations with L. plantarum alone or in combination with Lactobacillus brevis minimally improved the conversion of sugars. However, inoculation of the pure allochthonous MDC-deficient starter culture to 10 7 CFU per ml in acidified fermentations resulted in a reduced bloater index as compared to wild fermentations and those inoculated with the mixed starter culture. Although use of an allochthonous MDC-deficient starter culture reduces bloater index in acidified cucumber fermentations brined with CaCl 2 , an incomplete conversion of sugars is observed. Economical losses due to the incidence of bloaters in commercial cucumber fermentations brined with CaCl 2 may be reduced utilizing a starter culture to high cell density. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Tuning Chocolate Flavor through Development of Thermotolerant Saccharomyces cerevisiae Starter Cultures with Increased Acetate Ester Production

PubMed Central

Meersman, Esther; Steensels, Jan; Struyf, Nore; Paulus, Tinneke; Saels, Veerle; Mathawan, Melissa; Allegaert, Leen; Vrancken, Gino

2015-01-01

Microbial starter cultures have extensively been used to enhance the consistency and efficiency of industrial fermentations. Despite the advantages of such controlled fermentations, the fermentation involved in the production of chocolate is still a spontaneous process that relies on the natural microbiota at cocoa farms. However, recent studies indicate that certain thermotolerant Saccharomyces cerevisiae cultures can be used as starter cultures for cocoa pulp fermentation. In this study, we investigate the potential of specifically developed starter cultures to modulate chocolate aroma. Specifically, we developed several new S. cerevisiae hybrids that combine thermotolerance and efficient cocoa pulp fermentation with a high production of volatile flavor-active esters. In addition, we investigated the potential of two strains of two non-Saccharomyces species that produce very large amounts of fruity esters (Pichia kluyveri and Cyberlindnera fabianii) to modulate chocolate aroma. Gas chromatography-mass spectrometry (GC-MS) analysis of the cocoa liquor revealed an increased concentration of various flavor-active esters and a decrease in spoilage-related off-flavors in batches inoculated with S. cerevisiae starter cultures and, to a lesser extent, in batches inoculated with P. kluyveri and Cyb. fabianii. Additionally, GC-MS analysis of chocolate samples revealed that while most short-chain esters evaporated during conching, longer and more-fat-soluble ethyl and acetate esters, such as ethyl octanoate, phenylethyl acetate, ethyl phenylacetate, ethyl decanoate, and ethyl dodecanoate, remained almost unaffected. Sensory analysis by an expert panel confirmed significant differences in the aromas of chocolates produced with different starter cultures. Together, these results show that the selection of different yeast cultures opens novel avenues for modulating chocolate flavor. PMID:26590272

Tuning Chocolate Flavor through Development of Thermotolerant Saccharomyces cerevisiae Starter Cultures with Increased Acetate Ester Production.

PubMed

Meersman, Esther; Steensels, Jan; Struyf, Nore; Paulus, Tinneke; Saels, Veerle; Mathawan, Melissa; Allegaert, Leen; Vrancken, Gino; Verstrepen, Kevin J

2016-01-15

Microbial starter cultures have extensively been used to enhance the consistency and efficiency of industrial fermentations. Despite the advantages of such controlled fermentations, the fermentation involved in the production of chocolate is still a spontaneous process that relies on the natural microbiota at cocoa farms. However, recent studies indicate that certain thermotolerant Saccharomyces cerevisiae cultures can be used as starter cultures for cocoa pulp fermentation. In this study, we investigate the potential of specifically developed starter cultures to modulate chocolate aroma. Specifically, we developed several new S. cerevisiae hybrids that combine thermotolerance and efficient cocoa pulp fermentation with a high production of volatile flavor-active esters. In addition, we investigated the potential of two strains of two non-Saccharomyces species that produce very large amounts of fruity esters (Pichia kluyveri and Cyberlindnera fabianii) to modulate chocolate aroma. Gas chromatography-mass spectrometry (GC-MS) analysis of the cocoa liquor revealed an increased concentration of various flavor-active esters and a decrease in spoilage-related off-flavors in batches inoculated with S. cerevisiae starter cultures and, to a lesser extent, in batches inoculated with P. kluyveri and Cyb. fabianii. Additionally, GC-MS analysis of chocolate samples revealed that while most short-chain esters evaporated during conching, longer and more-fat-soluble ethyl and acetate esters, such as ethyl octanoate, phenylethyl acetate, ethyl phenylacetate, ethyl decanoate, and ethyl dodecanoate, remained almost unaffected. Sensory analysis by an expert panel confirmed significant differences in the aromas of chocolates produced with different starter cultures. Together, these results show that the selection of different yeast cultures opens novel avenues for modulating chocolate flavor. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Reduction of Biogenic Amines during Miso Fermentation by Lactobacillus plantarum as a Starter Culture.

PubMed

Lee, Yi-Chen; Kung, Hsien-Feng; Huang, Ya-Ling; Wu, Chien-Hui; Huang, Yu-Ru; Tsai, Yung-Hsiang

2016-09-01

Lactobacillus plantarum D-103 isolated from a miso product that possesses amine-degrading activity was used as a starter culture in miso fermentation (25°C for 120 days) in this study. The salt content in control samples (without starter culture) and inoculated samples (inoculated with L. plantarum D-103) remained constant at 10.4% of the original salt concentration throughout fermentation, whereas the pH value decreased from 6.2 to 4.6 during fermentation. The inoculated samples had significantly lower (P < 0.05) levels of total volatile basic nitrogen than control samples after 40 days of fermentation. After 120 days of fermentation, the histamine and overall biogenic amine contents in inoculated samples were reduced by 58 and 27%, respectively, compared with control samples. To our knowledge, this is the first report to demonstrate that application of a starter culture with amine-degrading activity in miso products was effective in reducing the accumulation of biogenic amines.

Evaluation of Mixed Probiotic Starter Cultures Isolated from Kimchi on Physicochemical and Functional Properties, and Volatile Compounds of Fermented Hams.

PubMed

Kim, Young Joo; Park, Sung Yong; Lee, Hong Chul; Yoo, Seung Seok; Oh, Sejong; Kim, Kwang Hyun; Chin, Koo Bok

2016-01-01

The objective of this study was to investigate the effects of mixed starter cultures isolated from kimchi on physicochemical properties, functionality and flavors of fermented ham. Physicochemical properties, microbial counts, shear force, cholesterol contents and volatile compounds of fermented ham were investigated during processing (curing and ripening time). Curing process for 7 d increased saltiness, however, decreased hunter color values (L, a, and b values). Ripening process for 21 d increased most parameters, such as saltiness, color values, weight loss, shear force and cholesterol content due to the drying process. The mixed starter culture had higher lactic acid bacteria than the commercial one. While eight volatile compounds were identified from fermented hams during curing process, total fiftyeight volatile compounds were identified from fermented hams during ripening process. The main volatile compounds were alcohols, esters and furans. However, no differences in volatile compounds were observed between two batches. Fermented hams (batch B) manufactured with probiotic starter culture (LPP) had higher sensory score in texture, color and overall acceptability than counterparts (batch A), while the opposite trend was observed in flavor. Therefore, mixed probiotic starter culture isolated from kimchi might be used as a starter culture to be able to replace with commercial starter culture (LK-30 plus) for the manufacture of fermented ham.

Evaluation of Mixed Probiotic Starter Cultures Isolated from Kimchi on Physicochemical and Functional Properties, and Volatile Compounds of Fermented Hams

PubMed Central

Yoo, Seung Seok

2016-01-01

The objective of this study was to investigate the effects of mixed starter cultures isolated from kimchi on physicochemical properties, functionality and flavors of fermented ham. Physicochemical properties, microbial counts, shear force, cholesterol contents and volatile compounds of fermented ham were investigated during processing (curing and ripening time). Curing process for 7 d increased saltiness, however, decreased hunter color values (L, a, and b values). Ripening process for 21 d increased most parameters, such as saltiness, color values, weight loss, shear force and cholesterol content due to the drying process. The mixed starter culture had higher lactic acid bacteria than the commercial one. While eight volatile compounds were identified from fermented hams during curing process, total fiftyeight volatile compounds were identified from fermented hams during ripening process. The main volatile compounds were alcohols, esters and furans. However, no differences in volatile compounds were observed between two batches. Fermented hams (batch B) manufactured with probiotic starter culture (LPP) had higher sensory score in texture, color and overall acceptability than counterparts (batch A), while the opposite trend was observed in flavor. Therefore, mixed probiotic starter culture isolated from kimchi might be used as a starter culture to be able to replace with commercial starter culture (LK-30 plus) for the manufacture of fermented ham. PMID:27499673

Exopolysaccharide-forming Weissella strains as starter cultures for sorghum and wheat sourdoughs.

PubMed

Galle, Sandra; Schwab, Clarissa; Arendt, Elke; Gänzle, Michael

2010-05-12

The addition of sourdough fermented with lactic acid bacteria synthesizing organic acids and oligo- and exopolysaccharides (EPS) from sucrose enhances texture, nutritional value, shelf life, and machinability of wheat, rye, and gluten-free bread. This study compared acetate, mannitol, and oligosaccharide formation of EPS-producing strains of Weissella and Leuconostoc spp. to the traditional sourdough starter Lactobacillus sanfranciscensis. In broth, Leuconostoc strains generally formed acetate and mannitol, whereas Weissella produced only small amounts of acetate and no mannitol in the presence of sucrose. In the presence of sucrose and maltose, Weissella and Leuconostoc strains synthesized glucooligosaccharides and EPS. Strains of Weissella were employed as starter cultures for wheat and sorghum sourdough and formed 0.8-8 g kg(-1) EPS and gluco-oligosaccharides but only low amounts of acetate and mannitol. In contrast, the formation of EPS from sucrose led to the production of high amounts of acetate and mannitol by L. sanfranciscensis LTH 2950 in wheat sourdough. This study indicates that Weissella strains are suitable starter cultures for wheat and sorghum sourdoughs and efficiently produce gluco-oligosaccharides and EPS.

Probiotic viability and storage stability of yogurts and fermented milks prepared with several mixtures of lactic acid bacteria.

PubMed

Mani-López, E; Palou, E; López-Malo, A

2014-05-01

Currently, the food industry wants to expand the range of probiotic yogurts but each probiotic bacteria offers different and specific health benefits. Little information exists on the influence of probiotic strains on physicochemical properties and sensory characteristics of yogurts and fermented milks. Six probiotic yogurts or fermented milks and 1 control yogurt were prepared, and we evaluated several physicochemical properties (pH, titratable acidity, texture, color, and syneresis), microbial viability of starter cultures (Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus) and probiotics (Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus reuteri) during fermentation and storage (35 d at 5°C), as well as sensory preference among them. Decreases in pH (0.17 to 0.50 units) and increases in titratable acidity (0.09 to 0.29%) were observed during storage. Only the yogurt with S. thermophilus, L. delbrueckii ssp. bulgaricus, and L. reuteri differed in firmness. No differences in adhesiveness were determined among the tested yogurts, fermented milks, and the control. Syneresis was in the range of 45 to 58%. No changes in color during storage were observed and no color differences were detected among the evaluated fermented milk products. Counts of S. thermophilus decreased from 1.8 to 3.5 log during storage. Counts of L. delbrueckii ssp. bulgaricus also decreased in probiotic yogurts and varied from 30 to 50% of initial population. Probiotic bacteria also lost viability throughout storage, although the 3 probiotic fermented milks maintained counts ≥ 10(7)cfu/mL for 3 wk. Probiotic bacteria had variable viability in yogurts, maintaining counts of L. acidophilus ≥ 10(7) cfu/mL for 35 d, of L. casei for 7d, and of L. reuteri for 14 d. We found no significant sensory preference among the 6 probiotic yogurts and fermented milks or the control. However, the yogurt and fermented milk made with L. casei were better accepted. This

Descriptive analysis and early-stage consumer acceptance of yogurts fermented with carrot juice.

PubMed

Cliff, M A; Fan, L; Sanford, K; Stanich, K; Doucette, C; Raymond, N

2013-07-01

This research explored the sensory characteristics and consumer acceptance of novel probiotic unsweetened yogurts. Yogurts were made with 4 carrot juice levels (8, 16, 24, and 32%), 2 firmness levels (regular, 45g/L milk solids; firm, 90g/L milk solids), and 2 starter cultures (C1, C2). The sensory profile characterized the color intensity (before and after stirring), carrot flavor, sourness, and 7 texture/mouth-feel attributes (astringency, chalkiness, mouth-coating, thickness, smoothness, creaminess, and graininess). The influence of carrot juice level and firmness level were evaluated using ANOVA, polynomial contrasts, and principal component analysis. Mean scores and standard errors were calculated. Consumer acceptance panels in Wolfville, Nova Scotia (n=56), and in Vancouver, British Columbia (Asian n=72, non-Asian n=72), evaluated the hedonic responses to the C1 and C2 formulations, respectively. We observed increases in color intensity, carrot flavor, creaminess, mouth-coating, and chalkiness with increasing carrot juice levels, as well as increases in color intensity, carrot flavor, creaminess, mouth-coating, thickness, and astringency with increasing milk solids concentrations of the C1 and C2 yogurts. Mean hedonic scores for color, appearance, and texture/mouth-feel were greater than hedonic scores for aroma, flavor/taste, and overall liking. This research identified the sensory qualities that need further development and demonstrated the importance of early-stage consumer acceptance research for directing new product development. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Microbial diversity of a Camembert-type cheese using freeze-dried Tibetan kefir coculture as starter culture by culture-dependent and culture-independent methods.

PubMed

Mei, Jun; Guo, Qizhen; Wu, Yan; Li, Yunfei

2014-01-01

The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM) methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates). Meanwhile, Kazachstania servazzii (51 isolates) represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates). However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved) cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese.

Microbial Diversity of a Camembert-Type Cheese Using Freeze-Dried Tibetan Kefir Coculture as Starter Culture by Culture-Dependent and Culture-Independent Methods

PubMed Central

Mei, Jun; Guo, Qizhen; Wu, Yan; Li, Yunfei

2014-01-01

The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM) methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates). Meanwhile, Kazachstania servazzii (51 isolates) represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates). However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved) cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese. PMID:25360757

Lactobacillus plantarum (KACC 92189) as a Potential Probiotic Starter Culture for Quality Improvement of Fermented Sausages

PubMed Central

2018-01-01

This study was conducted to evaluate the effects of fermenting temperature on the applicability of Lactobacillus plantarum for production of fermented sausages as starter cultures, and its applicable efficiency was also compared with those inoculated with commercial starter culture or non-inoculated control. The L. plantarum isolated from a naturally-fermented meat, identified by 16S rDNA sequencing and again identified by de novo Assembly Analysis method was used as a starter culture. Six treatments: 3 with L. plantarum at different fermenting temperatures (20, 25 and 30°C), and other 3 treatments (1 with commercial starter culture, 1 with its mixture with L. plantarum and 1 non-inoculated control) fermented under the same conditions (25°C) were prepared. Results revealed that the fermenting temperature considerably affected the pH change in samples added with L. plantarum; the highest pH drop rate (1.57 unit) was obtained on the samples fermented at 30°C, followed by those at 25°C (1.3 unit) and 20°C (0.99 unit) after 4 days fermentation. Increasing the temperature up to 30°C resulted in significantly lower spoilage bacteria count (5.15 log CFU/g) and lipid oxidation level in the products inoculated with L. plantarum. The sensory analysis also showed that the samples added with L. plantarum at 30°C had significantly higher odor, taste and acceptability scores than those fermented at lower temperatures. Under the same processing condition, although the L. plantarum showed slightly lower acidification than the commercial starter culture, however, it significantly improved the eating quality of the product. PMID:29725237

Physiochemical Properties and Probiotic Survivability of Symbiotic Corn-Based Yogurt-Like Product.

PubMed

Wang, Cuina; Zheng, Huajie; Liu, Tingting; Wang, Dawei; Guo, Mingruo

2017-09-01

Corn is a major grain produced in northern China. Corn-based functional food products are very limited. In this study, a symbiotic corn-based yogurt-like product was developed. Corn milk was prepared through grinding, extrusion and milling, and hydration processes. Corn extrudate was prepared under the optimized conditions of corn flour particle size <180 μm, moisture content of 15% and extrusion temperature at 130 °C. The corn milk was prepared from 8% corn extrudate suspension and then milled twice with 0.1% glyceryl monostearate and 0.1% sucrose ester as emulsifiers. The corn milk was mixed with sugar (5%), glucose (2%), soy protein isolate (0.75%), inulin (1%), polymerized whey protein (0.3%) and xanthan gum (0.09%) as thickening agents. The mixture was fermented at 35 °C for 6 h using a probiotic starter culture containing L. plantarum. Chemical composition (%) of the symbiotic corn-based yogurt-like product was: total solids (17.13 ± 0.31), protein (1.12 ± 0.03), fat (0.30 ± 0.05), carbohydrates (15.14 ± 0.19), and ash (0.16 ± 0.02), respectively. pH value of this symbiotic product decreased from 4.50 ± 0.03 to 3.88 ± 0.13 and the population of L. plantarum declined from 7.8 ± 0.09 to 7.1 ± 0.14 log CFU/mL during storage at 4 °C. SDS-PAGE analysis showed that there were no changes in protein profile during storage. Texture and consistency were also stable during the period of this study. It can be concluded that a set-type corn-based symbiotic yogurt-like product with good texture and stability was successfully developed that would be a good alternative to the dairy yogurt. © 2017 Institute of Food Technologists®.

Viability of Staphylococcus xylosus isolated from artisanal sausages for application as starter cultures in meat products.

PubMed

Fiorentini, Angela Maria; Sawitzki, Maristela Cortez; Bertol, Teresinha Marisa; Sant'anna, Ernani S

2009-01-01

Viability of Staphylococcus xylosus isolated from artisanal sausages for application as starter cultures in meat products Viability of Staphylococcus xylosus strains AD1 and U5 isolated from natural fermented sausages was investigated as starter cultures in fermented sausages produced in the South Region of Brazil. The study demonstrated that the Staphylococcus xylosus strains AD1 and U5 showed significant growth during fermentation, stability over freeze-dried process, negative reaction for staphylococcal enterotoxins and viability for using as a single-strain culture or associated with lactic acid bacteria for production of fermented sausages.

Effects of fermentation with Lactobacillus rhamnosus GG on product quality and fatty acids of goat milk yogurt.

PubMed

Jia, Ru; Chen, Han; Chen, Hui; Ding, Wu

2016-01-01

The effect of fermentation with Lactobacillus rhamnosus GG on the product quality of goat milk yogurt using traditional yogurt starter was studied through single-factor experiments and orthogonal experiments. The optimum fermentation condition was evaluated by the titratable acidity of goat milk yogurt, water-retaining capability, sensory score, and texture properties; the fatty acids of the fermented goat milk were determined by a gas chromatograph. Results indicate that high product quality of goat milk yogurt can be obtained and the content of short-chain and medium-chain fatty acids can be decreased significantly when amount of sugar added was 7%, inoculation amount was 3%, the ratio of 3 lactic acid bacteria--Lactobacillus delbrueckii ssp. bulgaricus, Streptococcus thermophilus, and L. rhamnosus GG--was 1:1:3, and fermentation temperature was 42°C. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Evaluation of Fermented Sausages Manufactured with Reduced-fat and Functional Starter Cultures on Physicochemical, Functional and Flavor Characteristics

PubMed Central

Yoo, Seung Seok

2014-01-01

Fermented foods with probiotics having functional properties may provide beneficial effects on health. These effects are varied, depending on the type of lactic acid bacteria (LAB). Different probiotic LAB might have different functional properties. Thus, this study was performed to evaluate the quality of fermented sausages manufactured with functional starter cultures (Lactobacillus plantarum 115 and 167, and Pediococcus damnosus L12) and different fat levels, and to determine the optimum condition for the manufacture of these products. Medium-fat (~15%) fermented sausages reduced the drying time and cholesterol contents, as compared to regular-fat counterparts. In proximate analysis, the contents of moisture and protein of regular-fat products were lower than medium-fat with reduced fat content. The regular-fat products also had a lighter color and less redness, due to reduced fat content. Approximately 35 volatile compounds were identified in functional fermented sausages, and hexanal, trans-caryophyllene, and tetradecanal were the major volatile compounds. Selected mixed starter culture showed the potential possibility of replacing the commercial starter culture (LK30 plus) in flavor profiles. However, medium-fat fermented sausage containing selected mixed starter culture tended to be less acceptable than their high-fat counterparts, due to excess dry ring developed in the surface. These results indicate that the use of combinations of L. plantarum 115 and 167, and P. damnosus L12 as a starter culture, will prove useful for manufacturing the fermented sausage. PMID:26761176

Viability of Staphylococcus xylosus isolated from artisanal sausages for application as starter cultures in meat products

PubMed Central

Fiorentini, Ângela Maria; Sawitzki, Maristela Cortez; Bertol, Teresinha Marisa; Sant’Anna, Ernani S.

2009-01-01

Viability of Staphylococcus xylosus isolated from artisanal sausages for application as starter cultures in meat products Viability of Staphylococcus xylosus strains AD1 and U5 isolated from natural fermented sausages was investigated as starter cultures in fermented sausages produced in the South Region of Brazil. The study demonstrated that the Staphylococcus xylosus strains AD1 and U5 showed significant growth during fermentation, stability over freeze-dried process, negative reaction for staphylococcal enterotoxins and viability for using as a single-strain culture or associated with lactic acid bacteria for production of fermented sausages. PMID:24031331

Effect of starter cultures on survival of Listeria monocytogenes in Čajna sausage

NASA Astrophysics Data System (ADS)

Bošković, M.; Tadić, V.; Đorđević, J.; Glišić, M.; Lakićević, B.; Dimitrijević, M.; Baltić, M. Ž.

2017-09-01

The aim of the study was to evaluate the survival of Listeria monocytogenes during the production of Čajna sausage with short maturation time. Sausage batter was inoculated with three different serotypes 4b and serotype 1/2a of L. monocytogenes. Control sausages were without any starter culture added; the second batch was inoculated with strains of Lactobacillus sakei, Staphylococcus carnosus and Staphylococcus xylosus, and the third batch was inoculated with strains of Debaryomyces hansenii, Lactobacillus sakei, Pediococcus acidilactici, Pediococcus pentosaceus, Staphylococcus carnosus and Staphylococcus xylosus. After 18 days of ripening, L. monocytogenes was not detected in any of the sausages, but during this fermentation and drying, the numbers of this pathogen was lower in the sausages inoculated with starter cultures.

Metagenomics analysis of microbial communities associated with a traditional rice wine starter culture (Xaj-pitha) of Assam, India.

PubMed

Bora, Sudipta Sankar; Keot, Jyotshna; Das, Saurav; Sarma, Kishore; Barooah, Madhumita

2016-12-01

This is the first report on the microbial diversity of xaj-pitha, a rice wine fermentation starter culture through a metagenomics approach involving Illumine-based whole genome shotgun (WGS) sequencing method. Metagenomic DNA was extracted from rice wine starter culture concocted by Ahom community of Assam and analyzed using a MiSeq ® System. A total of 2,78,231 contigs, with an average read length of 640.13 bp, were obtained. Data obtained from the use of several taxonomic profiling tools were compared with previously reported microbial diversity studies through the culture-dependent and culture-independent method. The microbial community revealed the existence of amylase producers, such as Rhizopus delemar, Mucor circinelloides, and Aspergillus sp. Ethanol producers viz., Meyerozyma guilliermondii, Wickerhamomyces ciferrii, Saccharomyces cerevisiae, Candida glabrata, Debaryomyces hansenii, Ogataea parapolymorpha, and Dekkera bruxellensis, were found associated with the starter culture along with a diverse range of opportunistic contaminants. The bacterial microflora was dominated by lactic acid bacteria (LAB). The most frequent occurring LAB was Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc lactis, Weissella cibaria, Lactococcus lactis, Weissella para mesenteroides, Leuconostoc pseudomesenteroides, etc. Our study provided a comprehensive picture of microbial diversity associated with rice wine fermentation starter and indicated the superiority of metagenomic sequencing over previously used techniques.

Effect of six different starter cultures on the concentration of residual nitrite in fermented sausages during in vitro human digestion.

PubMed

Kim, Hyeong Sang; Hur, Sun Jin

2018-01-15

The objective of this study was to determine the effect of six different starter cultures of enterobacteria on the concentration of residual nitrite in fermented sausages during in vitro human digestion. Before digestion, the concentration of residual nitrite was dependent on starter culture in fermented sausage and ranged from 25.2 to 33.2mg/kg. Among the six starter cultures of enterobacteria, Pediococcus acidilactici, Pediococcus pentosaceus, and Staphylococcus carnosus showed higher nitrite depletion ability than the other three strains in fermented sausages. The concentration of residual nitrite in fermented sausages was significantly (p<0.05) decreased after stomach digestion and ranged from 17.4 to 21.6mg/kg. Enterobacteria Escherichia coli (E. coli) and/or Lactobacillus casei (L. casei) effectively increased the degree of depletion of residual nitrite in large intestine digestion. In conclusion, starter cultures could influence the concentration of residual nitrite during in vitro human digestion. They could deplete residual nitrite in fermented sausages. Copyright © 2017 Elsevier Ltd. All rights reserved.

Halobacterium sp. SP1(1) as a starter culture for accelerating fish sauce fermentation.

PubMed

Akolkar, A V; Durai, D; Desai, A J

2010-07-01

Application of Halobacterium sp. SP1(1) for the acceleration of fish sauce fermentation. Traditional fish sauce fermentation was mimicked using Halobacterium sp. SP1(1) as starter culture. Protease activity, peptide release and α-amino content (parameters used to monitor the progress of the fermentation) were high at day 10 in tests and day 20 in un-inoculated controls. The total protein and nitrogen contents were also high in tests compared with controls. The amino acid profile observed at the end of fermentation in experimental samples, when compared with the commercial sauce preparation, was found to be better with respect to flavour and aroma contributing amino acids as well as essential amino acid lysine. Microflora analysis of the final fish sauce revealed the absence of any nonhalophilic or halotolerant micro-organisms. The protease-producing halophilic isolates obtained from the fish sauce of eviscerated and uneviscerated controls were identified as Halobacterium sp. F1 and F2, respectively, by 16S rDNA sequence analysis. Exogenous augmentation of Halobacterium sp. SP1(1) accelerated the fish sauce fermentation process with an additive effect on the existing natural microflora present in the fish during fermentation. Halobacterium sp SP1(1), therefore, can be used as an important starter culture for accelerating the fish fermentation process, which is attributed to its extracellular protease. The present study is the first report on use of Halobacterium species as a starter culture for accelerating fish sauce fermentation. Use of halobacterial starter cultures may revolutionize the process in fish sauce industries by reducing the fermentation time and making the process more economical with improved nutritive value of product. Journal compilation © 2009 The Society for Applied Microbiology. No claim to Indian Government works.

Streptococcus thermophilus APC151 Strain Is Suitable for the Manufacture of Naturally GABA-Enriched Bioactive Yogurt.

PubMed

Linares, Daniel M; O'Callaghan, Tom F; O'Connor, Paula M; Ross, R P; Stanton, Catherine

2016-01-01

Consumer interest in health-promoting food products is a major driving force for the increasing global demand of functional (probiotic) dairy foods. Yogurt is considered the ideal medium for delivery of beneficial functional ingredients. Gamma-amino-butyric acid has potential as a bioactive ingredient in functional foods due to its health-promoting properties as an anti-stress, anti-hypertensive, and anti-diabetic agent. Here, we report the use of a novel Streptococcus thermophilus strain, isolated from the digestive tract of fish, for production of yogurt naturally enriched with 2 mg/ml of gamma-amino-butyric acid (200 mg in a standard yogurt volume of 100 ml), a dose in the same range as that provided by some commercially available gamma-amino-butyric acid supplements. The biotechnological suitability of this strain for industrial production of yogurt was demonstrated by comparison with the reference yogurt inoculated with the commercial CH1 starter (Chr. Hansen) widely used in the dairy industry. Both yogurts showed comparable pH curves [ΔpH/Δ t = 0.31-0.33 h -1 ], viscosity [0.49 Pa-s], water holding capacity [72-73%], and chemical composition [moisture (87-88%), protein (5.05-5.65%), fat (0.12-0.15%), sugar (4.8-5.8%), and ash (0.74-1.2%)]. Gamma-amino-butyric acid was not detected in the control yogurt. In conclusion, the S. thermophilus APC151 strain reported here provides a natural means for fortification of yogurt with gamma-amino-butyric acid.

Effect of proteolytic starter cultures as leavening agents of pizza dough.

PubMed

Pepe, O; Villani, F; Oliviero, D; Greco, T; Coppola, S

2003-08-01

Lactic acid bacteria (LAB) and yeasts were selected on the basis of in vitro proteolytic activity against wheat gluten protein and then assayed as leavening agents for pizza dough. Trials were carried out to compare a proteolytic starter (Prt(+)), consisting of Lactobacillus sakei T56, Weissella paramesenteroides A51 and Candida krusei G271, and a non-proteolytic starter (Prt(-)), consisting of Lb. sakei T58, W. paramesenteroides A58 and Saccharomyces cerevisiae T22. The proteolytic activity of the starter cultures was monitored immediately after mixing of the dough and throughout the fermentation process. The proteolytic activity was assessed by analysing the salt-soluble protein (SSP) and the dioxane-soluble protein (DSP) fractions of the pizza dough by discontinuous SDS-PAGE. Only the Prt(+) starter exhibited considerable qualitative and quantitative changes in the electrophoretic patterns of the protein fractions extracted. After the fermentation, the Prt(+) and Prt(-) doughs were tested to evaluate the influence of the proteolytic activity on the mechanical properties of the dough before and after baking. Indications emerged suggesting an influence of the proteolytic activity on the viscoelasticity of pizza dough. The pizza dough with Prt(+) strains showed an increase in viscous properties during the fermentation as compared with the Prt(-) dough. Moreover, an increase in the firmness of the crumb was observed in Prt(+) baked pizza dough.

The integration methods of fuzzy fault mode and effect analysis and fault tree analysis for risk analysis of yogurt production

NASA Astrophysics Data System (ADS)

Aprilia, Ayu Rizky; Santoso, Imam; Ekasari, Dhita Murita

2017-05-01

Yogurt is a product based on milk, which has beneficial effects for health. The process for the production of yogurt is very susceptible to failure because it involves bacteria and fermentation. For an industry, the risks may cause harm and have a negative impact. In order for a product to be successful and profitable, it requires the analysis of risks that may occur during the production process. Risk analysis can identify the risks in detail and prevent as well as determine its handling, so that the risks can be minimized. Therefore, this study will analyze the risks of the production process with a case study in CV.XYZ. The method used in this research is the Fuzzy Failure Mode and Effect Analysis (fuzzy FMEA) and Fault Tree Analysis (FTA). The results showed that there are 6 risks from equipment variables, raw material variables, and process variables. Those risks include the critical risk, which is the risk of a lack of an aseptic process, more specifically if starter yogurt is damaged due to contamination by fungus or other bacteria and a lack of sanitation equipment. The results of quantitative analysis of FTA showed that the highest probability is the probability of the lack of an aseptic process, with a risk of 3.902%. The recommendations for improvement include establishing SOPs (Standard Operating Procedures), which include the process, workers, and environment, controlling the starter of yogurt and improving the production planning and sanitation equipment using hot water immersion.

[Identification of lactic acid bacteria in commercial yogurt and their antibiotic resistance].

PubMed

Qin, Yuxuan; Li, Jing; Wang, Qiuya; Gao, Kexin; Zhu, Baoli; Lv, Na

2013-08-04

To identify lactic acid bacteria (LAB) in commercial yogurts and investigate their antibiotic resistance. LABs were cultured from 5 yogurt brands and the isolates were identified at the species level by 16S rRNA sequence. Genotyping was performed by repetitive extragenic palindromic PCR (rep-PCR). The sensitivity to 7 antibiotics was tested for all LAB isolates by Kirby-Bauer paper diffusion (K-B method). Meanwhile, 9 antibiotic resistance genes (ARGs), including erythromycin resistance genes (ermA and ermB) and tetracycline resistance genes (tetM, tetK, tetS, tetQ, tetO, tetL and tetW), were detected by PCR amplification in the identified LAB isolates. The PCR products were confirmed by sequencing. Total 100 LABs were isolated, including 23 Lactobacillus delbrueckii ssp. bulgaricus, 26 Lactobacillus casei, 30 Streptococcus thermophilus, 5 Lactobacillus acidophilus, 6 Lactobacillus plantarum, and 10 Lactobacillus paracasei. The drug susceptibility test shows that all 100 isolates were resistant to gentamicin and streptomycin, 42 isolates were resistant to vancomycin, and on the contrary all were sensitive to cefalexin, erythromycin, tetracycline and oxytetracycline. Moreover, 5 ARGs were found in the 28 sequencing confirmed isolates, ermB gene was detected in 8 isolates, tet K in 4 isolates, tetL in 2 isolates, tetM in 4 isolates, tetO in 2 isolates. erm A, tet S, tet Q and tet W genes were not detected in the isolates. Antibiotic resistance genes were found in 53.57% (15/28) sequenced isolates, 2 -3 antibiotic resistance genes were detected in 4 isolates of L. delbrueckii ssp. bulgaricus. Some LABs were not labeled in commercial yogurt products. Antibiotic resistance genes tend to be found in the starter culture of L. delbrueckii ssp. Bulgaricus and S. thermophilus. All the LAB isolates were sensitive to erythromycin and tetracycline, even though some carried erythromycin and/or tetracycline resistance genes. We proved again that LAB could carry antibiotic

Introduction to the Yogurt in Nutrition Initiative at the First Symposium of Yogurt in Mexico: The Balanced Diet Initiative.

PubMed

Tovar, Armando R; Herrera, Guadalupe

2017-01-01

In some European countries, yogurt consumption is common. However, such consumption is not common in Latin America, particularly in Mexico, partially because of the lack of a cultural tradition of consuming yogurt. Moreover, we also know that little information about the health benefits associated with yogurt consumption has been provided to the Mexican population. Thus, there is an immediate need to provide, at least to the nutrition community in the country, current scientific evidence about the health benefits of yogurt, with the aim that yogurt be included as part of the functional foods recommended to the population. Currently, extensive research has been conducted to investigate the mechanisms through which yogurt generates beneficial effects. Gut microbiota appear to be an important factor that can be modified by dietary prebiotics, as well as probiotics such as yogurt. The prevention or attenuation of gut microbiota dysbiosis is now associated with improvements observed in individuals with metabolic syndrome and cardiovascular disease. Thus, it is important to establish guidelines for the consumption of dairy products, including yogurt. Such guidelines are necessary to increase the consumption of dairy products in Mexico and other countries. © 2017 American Society for Nutrition.

Modeling of rheological characteristics of the fermented dairy products obtained by novel and traditional starter cultures.

PubMed

Vukić, Dajana V; Vukić, Vladimir R; Milanović, Spasenija D; Ilicić, Mirela D; Kanurić, Katarina G

2018-06-01

Tree different fermented dairy products obtained by conventional and non-conventional starter cultures were investigated in this paper. Textural and rheological characteristics as well as chemical composition during 21 days of storage were analysed and subsequent data processing was performed by principal component analysis. The analysis of samples` flow behaviour was focused on their time dependent properties. Parameters of Power law model described flow behaviour of samples depended on used starter culture and days of storage. The Power law model was applied successfully to describe the flow of the fermented milk, which had characteristics of shear thinning and non-Newtonian fluid behaviour.

Streptococcus thermophilus APC151 Strain Is Suitable for the Manufacture of Naturally GABA-Enriched Bioactive Yogurt

PubMed Central

Linares, Daniel M.; O’Callaghan, Tom F.; O’Connor, Paula M.; Ross, R. P.; Stanton, Catherine

2016-01-01

Consumer interest in health-promoting food products is a major driving force for the increasing global demand of functional (probiotic) dairy foods. Yogurt is considered the ideal medium for delivery of beneficial functional ingredients. Gamma-amino-butyric acid has potential as a bioactive ingredient in functional foods due to its health-promoting properties as an anti-stress, anti-hypertensive, and anti-diabetic agent. Here, we report the use of a novel Streptococcus thermophilus strain, isolated from the digestive tract of fish, for production of yogurt naturally enriched with 2 mg/ml of gamma-amino-butyric acid (200 mg in a standard yogurt volume of 100 ml), a dose in the same range as that provided by some commercially available gamma-amino-butyric acid supplements. The biotechnological suitability of this strain for industrial production of yogurt was demonstrated by comparison with the reference yogurt inoculated with the commercial CH1 starter (Chr. Hansen) widely used in the dairy industry. Both yogurts showed comparable pH curves [ΔpH/Δt = 0.31-0.33 h-1], viscosity [0.49 Pa-s], water holding capacity [72–73%], and chemical composition [moisture (87–88%), protein (5.05–5.65%), fat (0.12–0.15%), sugar (4.8–5.8%), and ash (0.74–1.2%)]. Gamma-amino-butyric acid was not detected in the control yogurt. In conclusion, the S. thermophilus APC151 strain reported here provides a natural means for fortification of yogurt with gamma-amino-butyric acid. PMID:27920772

Amino acid profile and sensory characteristics of dry fermented pork loins produced with a mixture of probiotic starter cultures.

PubMed

Neffe-Skocińska, Katarzyna; Okoń, Anna; Kołożyn-Krajewska, Danuta; Dolatowski, Zbigniew

2017-07-01

Proteolysis is a biochemical process in dry-aged meat products where proteins are metabolized and broken down to polypeptides, peptides, and free amino acids. In the literature it is reported that an appropriate choice of probiotic starter culture limits proteolytic changes in dry-fermented meat products. In this study the combined effect of a mixture of probiotic starter cultures on the free amino acid profile, total count of lactic acid bacteria, and the sensory quality of dry-aged pork loins after fermentation and after storing the vacuum-packed samples was evaluated. LOCK900 and BB12 probiotic strains were the technologically best two-species mixture of starter cultures for the production of probiotic dry-aged pork loins. They allowed us to obtain products with high and stable bacterial count and acceptable sensory quality, both after 21 days of fermentation and after 2 months of cold storage. Changes in the free amino acid profile and increased intensity of the selected sensory attributes result from a significant share of probiotics in meat proteolysis occurring during fermentation and storage. The results suggest the relevance of using probiotic bacteria as a two-species starter culture for the production of dry-aged products. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Two efficient nitrite-reducing Lactobacillus strains isolated from traditional fermented pork (Nanx Wudl) as competitive starter cultures for Chinese fermented dry sausage.

PubMed

Chen, Xi; Li, Jiapeng; Zhou, Tong; Li, Jinchun; Yang, Junna; Chen, Wenhua; Xiong, Youling L

2016-11-01

Lactic acid bacteria isolated from traditional Dong pork product (Nanx Wudl) were investigated for their potential as starter cultures for Chinese fermented dry sausages. Based on preliminary screening, Lactobacillus plantarum CMRC6 and Lactobacillus sakei CMRC15, both showing excellent nitrite-reducing capacity, were used as single-strain starter cultures. For comparison, a commercial composite starter was also tested. In CMRC6 and CMRC15-inoculated sausages, lactic acid bacteria dominated the microflora and improved the microbiological safety by suppression of Enterobacteriaceae growth. Nitrite content of all inoculated sausages declined rapidly during ripening compared to non-inoculated. Texture profiles analysis showed inoculated sausages had more pronounced textural development during ripening. Sensory evaluation indicated CMRC6 and CMRC15-fermented sausages had comparable or more desirable organoleptic characteristics than sausage made with commercial starters. Therefore, CMRC6 and CMRC15 are promising candidates as multi-functional starter cultures for microbiological safety and residual nitrite control in gourmet Chinese dry sausage production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of an autochthonous starter culture on the production of a traditional dry fermented sausage from Chaco (Argentina) at a small-scale facility.

PubMed

Palavecino Prpich, Noelia Z; Garro, Oscar A; Romero, Mara; Judis, María A; Cayré, María E; Castro, Marcela P

2016-05-01

The performance of a mixed starter culture, SAS-1, comprised of the autochthonous strains Lactobacillus sakei ACU-2 and Staphylococcus vitulinus ACU-10, was evaluated into the production process of a traditional dry sausage. Microbiological, physicochemical and sensory analyses were carried out to accomplish this goal. Results showed an improvement in performance through the introduction of SAS-1; adding mixed starter culture rapidly decreased pH, inhibited the growth of contaminant microorganisms and enhanced the beneficial ones, diminished TBARS, and highlighted color and aroma attributes. However, most influential organoleptic descriptors among consumer acceptance were not affected by the addition of the starter. This starter culture would represent a valuable tool to improve the homogeneity of artisanal manufacture of this traditional food. Copyright © 2016 Elsevier Ltd. All rights reserved.

Aminogenesis control in fermented sausages manufactured with pressurized meat batter and starter culture.

PubMed

Latorre-Moratalla, M L; Bover-Cid, S; Aymerich, T; Marcos, B; Vidal-Carou, M C; Garriga, M

2007-03-01

The application of high hydrostatic pressure (200MPa) to meat batter just before sausage fermentation and the inoculation of starter culture were studied to improve the safety and quality of traditional Spanish fermented sausages (fuet and chorizo). Higher amounts of biogenic amines were formed in chorizo than in fuet. Without interfering with the ripening performance in terms of acidification, drying and proteolysis, hydrostatic pressure prevented enterobacteria growth but did not affect Gram-positive bacteria significantly. Subsequently, a strong inhibition of diamine (putrescine and cadaverine) accumulation was observed, but that of tyramine was not affected. The inoculated decarboxylase-negative strains, selected from indigenous bacteria of traditional sausages, were resistant to the HHP treatment, being able to lead the fermentation process, prevent enterococci development and significantly reduce enterobacteria counts. In sausages manufactured with either non-pressurized or pressurized meat batter, starter culture was the most protective measure against the accumulation of tyramine and both diamines.

Technological, rheological and sensory characterizations of a yogurt containing an exopolysaccharide extract from Lactobacillus fermentum Lf2, a new food additive.

PubMed

Ale, Elisa C; Perezlindo, Marcos J; Pavón, Yanina; Peralta, Guillermo H; Costa, Silvia; Sabbag, Nora; Bergamini, Carina; Reinheimer, Jorge A; Binetti, Ana G

2016-12-01

Lactobacillus fermentum Lf2, an autochthonous strain isolated as a non starter culture in Cremoso cheese, produces high EPS levels (~1g/L) in optimized conditions (SDM broth, pH6.0, 30°C, 72h). Technological (texture profile and rheological analysis) and sensory properties of non-fat yogurts with 300 and 600mg EPS/L were studied at 3 and 25days after manufacture. Yogurts with different EPS concentrations showed higher hardness values than the control group at both periods of time, being the only significant difference that remained stable during time. The consistency index was also higher for the treated samples at both times evaluated, being significantly different for samples with 300mg/L of EPS extract, while the flow behavior index was lower for EPS-added yogurts. The thixotropic index was lower (P<0.05) for samples with the highest EPS extract concentration at the end of the storage time. Regarding the sensory analysis, those yogurts with 600mg/L of EPS extract presented the highest values of consistency at 3days of storage. No considerable differences for defects (milk powder, acid, bitter and cooked milk flavors) were perceived between treated and control samples at both times evaluated. Syneresis was also studied and samples with 600mg/L of EPS extract presented the lowest syneresis values at 25days of storage, which considerably decreased with the time of storage. In conclusion, the EPS from L. fermentum Lf2, used as an additive, provided yogurt with creamy consistency and increased hardness, without the presence of unwanted defects and improving the water holding capacity of the product. All the analysis done showed the potential of this extract to be used as a technofunctional natural ingredient, and it should be considered its positive impact on health, according to previous studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Simultaneous analysis of carbohydrates and organic acids by HPLC-DAD-RI for monitoring goat's milk yogurts fermentation.

PubMed

da Costa, Marion Pereira; Frasao, Beatriz da Silva; Lima, Bruno Reis Carneiro da Costa; Rodrigues, Bruna Leal; Conte Junior, Carlos Adam

2016-05-15

During yogurt manufacture, the lactose fermentation and organic acid production can be used to monitor the fermentation process by starter cultures and probiotic bacteria. In the present work, a simple, sensitive and reproducible high-performance liquid chromatography with dual detectors, diode array detector and refractive index was validated by simultaneous analysis of carbohydrates and organic acids in goat milk yogurts. In addition, pH and bacterial analysis were performed. Separation of all the compounds was performed on an Aminex HPX-87H column (300×7.8 mm, 9 µm) utilizing a 3 mmol L(-1) sulfuric acid aqueous mobile phase under isocratic conditions. Lactose, glucose, galactose, citric, lactic and formic acids were used to evaluate the following performance parameters: selectivity, linearity, precision, limit of detection (LOD), limit of quantification (LOQ), decision limits (CCα), detection capabilities (CCβ), recovery and robustness. For the method application a six goat milk yogurts were elaborated: natural, probiotic, prebiotic, symbiotic, cupuassu fruit pulp, and probiotic with cupuassu fruit pulp. The validated method presented an excellent selectivity with no significant matrix effect, and a broad linear study range with coefficients of determination higher than 0.995. The relative standard deviation was lower than 10% under repeatability and within-laboratory reproducibility conditions for the studied analytes. The LOD of the method was defined from 0.001 to 0.003 µg g(-1), and the LOQ from 0.003 to 0.013 µg g(-1). The CCα was ranged from 0.032 to 0.943 µg g(-1), and the CCβ from 0.053 to 1.604 µg g(-1). The obtained recovery values were from 78% to 119%. In addition, the method exhibited an appropriate robustness for all parameter evaluated. Base in our data, it was concluded that the performance parameters demonstrated total method adequacy for the detection and quantification of carbohydrates and organic acids in goat milk yogurts. The

Characterization of aromatic properties of old-style cheese starters.

PubMed

Lacroix, N; St-Gelais, D; Champagne, C P; Fortin, J; Vuillemard, J-C

2010-08-01

Old-style cheese starters were evaluated to determine their ability to produce cheese aroma compounds. Detailed analyses of the aroma-producing potential of 13 old-style starter cultures were undertaken. The proteolytic profile of the starters was established by an accelerated ripening study using a model cheese slurry and compared with those of a commercial aromatic starter and commercial Cheddar cheeses. To evaluate the aromatic potential of the starter cultures, quantification of free amino acids liberated and volatile compounds after 15 d of ripening at 30 degrees C as well as sensory analysis were carried out. Results showed that proteolysis patterns of all 13 starter cultures in the curd model were comparable to those of commercial Cheddar cheeses. All tested cultures demonstrated the ability to produce high amounts of amino acids recognized as precursors of aroma compounds. Several differences were observed between the starters and commercial Cheddar cheeses regarding some amino acids such as glutamate, leucine, phenylalanine, proline, and ornithine, reflecting the various enzymatic systems present in the starters. Starters Bt (control) and ULAAC-E exhibited various significant differences regarding their free amino acid profiles, as confirmed by sensory analysis. In addition, identification of volatile compounds confirmed the presence of several key molecules related to aroma, such as 3-methylbutanal and diacetyl. Besides the aroma-producing aspect, 2 starters (ULAAC-A and ULAAC-H) seem to possess an important ability to generate large amounts of gamma-aminobutyric acid, which contributed up to 15% of the total amino acids present in the model curd after 15 d ripening. gamma-Aminobutyric acid is an amine well-known for its antihypertensive and calming effects. Copyright (c) 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Genome Sequence of Lactococcus raffinolactis Strain 4877, Isolated from Natural Dairy Starter Culture

PubMed Central

Meslier, Victoria; Loux, Valentin

2012-01-01

The nonstarter lactic acid bacterium Lactococcus raffinolactis is prevalent in a wide range of environments, such as the dairy environment, but little is known about this species. Here, we present the draft genome of Lactococcus raffinolactis strain 4877, isolated from a natural mesophilic dairy starter culture. PMID:23105090

Texture profile analysis of yogurt as influenced by partially hydrolyzed guar gum and process variables.

PubMed

Mudgil, Deepak; Barak, Sheweta; Khatkar, B S

2017-11-01

Effect of partially hydrolyzed guar gum (PHGG) level (1-5%), culture level (1.5-3.5%) and incubation time (4-8 h) on texture profile of yogurt was studied using response surface methodology. The fortification of partially hydrolyzed guar gum in yogurt decreased the firmness and gumminess while it increased the adhesiveness, cohesiveness and springiness of yogurt significantly at p  < 0.01. The culture level did not affect the textural properties of yogurt significantly except gumminess whereas textural properties of yogurt were negatively correlated with incubation time. The coefficient of determination for hardness/hardness, adhesiveness, cohesiveness, springiness and gumminess were 0.9216, 0.9397, 0.8914, 0.8971 and 0.9156, respectively, which revealed that the models obtained were significant as coefficient of determination value was close to one. The optimum conditions obtained were PHGG level 3.37%, culture level 1.96% and incubation time 5.96 h which leads to preparation of yogurt with desired textural characteristics.

Contribution of starter cultures to the proteolytic process of a fermented non-dried whole muscle ham product.

PubMed

Scannell, Amalia G M; Kenneally, Paul M; Arendt, Elke K

2004-06-01

Porcine longissimus dorsi muscles were cured by brine injection. Curing brine containing 15% (w/v) NaCl, 1.33% (w/v) glucose, 750 ppm sodium nitrite, and appropriate levels of either Lactobacillus sakei LAD, L. sakei LAD plus Kocuria varians FT4 (formally Micrococcus varians), L. sakei LAD plus papain and GDL (glucono-delta-lactone) plus K. varians FT4, was injected to the muscle at a pumping rate 15% w/v. The effect of these treatments on the proteolysis in the ham system was compared to a control ham, produced without starter culture and containing GDL acidulant to control pH and antibiotics to reduce the contribution of background microflora. Hydrolysis of sarcoplasmic and myofibrillar protein fractions was evaluated by SDS-PAGE and reverse phase-HPLC. Hams with different treatments were also investigated for differences in amino acid profile, protein and non-protein nitrogen level, colour, pH, water activity and moisture and microbiological evolution. There was no significant difference in the gross compositional analysis of any of the treatments compared to the control. There was no significant difference (p>0.05) in the protein content, non-protein nitrogen level, SDS-PAGE and free amino acid analysis between the control ham and ham inoculated with proteolytic starter culture. However, it was observed that hams containing starter cultures exhibited decreases in certain peptide fractions and corresponding increases in some free amino acids compared to the uninoculated control. It can be concluded that, while the principle mechanisms resulting in the proteolysis of this non-dried ham product involve the activity of endogeneous cathepsins, the addition of proteolytic starter cultures influence the amino acid profile thereby potentially enhancing the sensorial attributes of the ham. Copyright 2004 Elsevier B.V.

Effect of temperature on microbial composition of starter culture for Chinese light aroma style liquor fermentation.

PubMed

Wang, H Y; Xu, Y

2015-01-01

Light aroma style liquor is one of the basic types of Chinese liquor and is produced with a special technique of using a combination of three types of Daqu as starter culture. The succession of incubation temperature, a main operating parameter, and microbial composition in Daqu were investigated during the manufacturing process. The most significant difference in temperature occurred during the middle stage at which the highest and the lowest temperatures were detected in Houhuo (HH) and Qingcha (QC), respectively. It was shown that for the counting data, the population of fungi was identical and that of bacteria was different between three types of Daqu. According to analysis results of microbial community structure using PCR-denaturing gradient gel electrophoresis (PCR-DGGE), lactic acid bacteria were one of the dominant bacterial groups in all of Daqu and fungal diversity in QC was higher than that in HH and Hongxin (HX). The difference in incubation temperature led to the accumulation of different heat-tolerant and heat-sensitive fungi in the completed Daqu. PCA of DGGE profiles revealed that microbial community structure was distinct between three types of Daqu. It was presumed that temperature might play a decisive role in the formation of micro-organism composition in starter cultures. The usage of a combination of three types of Daqu including Qingcha, Hongxin and Houhuo as starter culture is an important characteristic of production technology of Chinese light aroma style liquor. Micro-organisms from the environment naturally inoculated in Daqu are propagated to form the special microbial community under the control of several operating parameters, especially temperature, and finally play various roles in the fermentation process of liquor. An in-depth study of the relationship between incubation temperature and microbiota in Daqu during the manufacturing is fundamental to understand this complicated process and to prepare high-quality starter culture for

Antibiotic susceptibility patterns and resistance genes of starter cultures and probiotic bacteria used in food.

PubMed

Kastner, Sabine; Perreten, Vincent; Bleuler, Helen; Hugenschmidt, Gabriel; Lacroix, Christophe; Meile, Leo

2006-03-01

A survey of starter and probiotic cultures was carried out to determine the current antibiotic resistance situation in microbial food additives in Switzerland. Two hundred isolates from 90 different sources were typed by molecular and other methods to belong to the genera Lactobacillus (74 samples), Staphylococcus (33 samples), Bifidobacterium (6 samples), Pediococcus (5 samples), or were categorized as lactococci or streptococci (82 samples). They were screened for phenotypic resistances to 20 antibiotics by the disk diffusion method. Twenty-seven isolates exhibiting resistances that are not an intrinsic feature of the respective genera were further analyzed by microarray hybridization as a tool to trace back phenotypic resistances to specific genetic determinants. Their presence was finally verified by PCR amplification or Southern hybridization. These studies resulted in the detection of the tetracycline resistance gene tet(K) in 5 Staphylococcus isolates used as meat starter cultures, the tetracycline resistance gene tet(W) in the probiotic cultures Bifidobacterium lactis DSM 10140 and Lactobacillus reuteri SD 2112 (residing on a plasmid), and the lincosamide resistance gene lnu(A) (formerly linA) in L. reuteri SD 2112.

Use of micellar casein concentrate for Greek-style yogurt manufacturing: effects on processing and product properties.

PubMed

Bong, D D; Moraru, C I

2014-03-01

The objective of this work was to develop and optimize an alternative make process for Greek-style yogurt (GSY), in which the desired level of protein was reached by fortification with micellar casein concentrate (MCC) obtained from milk by microfiltration. Two MCC preparations with 58 and 88% total protein (MCC-58 and MCC-88) were used to fortify yogurt milk to 9.80% (wt/wt) protein. Strained GSY of similar protein content was used as the control. Yogurt milk bases were inoculated with 0.02% (wt/wt) or 0.04% (wt/wt) direct vat set starter culture and fermented until pH 4.5. The acidification rate was faster for the MCC-fortified GSY than for the control, regardless of the inoculation level, which was attributed to the higher nonprotein nitrogen content in the MCC-fortified milk. Steady shear rate rheological analysis indicated a shear-thinning behavior for all GSY samples, which fitted well with the power law model. Dynamic rheological analysis at 5°C showed a weak frequency dependency of the elastic modulus (G') and viscous modulus (G") for all GSY samples, with G' > G", indicating a weak gel structure. Differences in the magnitude of viscoelastic parameters between the 2 types of GSY were found, with G' of MCC-fortified GSY < G' of control, indicating a different extent of protein interactionsin the 2 types of yogurt. Differences were also noticed in water-holding capacity, which was lower for the MCC-fortified GSY compared with the control, attributed to lower serum protein content in the former. Despite some differences in the physicochemical characteristics of the final product compared with GSY manufactured by straining, the alternative process developed here is a feasible alternative to the traditional GSY make process, with environmental and possibly financial benefits to the dairy industry. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Characterization of lactic acid bacteria isolated from infant faeces as potential probiotic starter cultures for fermented sausages.

PubMed

Rubio, Raquel; Jofré, Anna; Martín, Belén; Aymerich, Teresa; Garriga, Margarita

2014-04-01

A total of 109 lactic acid bacteria isolated from infant faeces were identified by partial 16S rRNA, cpn60 and/or pheS sequencing. Lactobacillus was the most prevalent genus, representing 48% of the isolates followed by Enterococcus (38%). Lactobacillus gasseri (21%) and Enterococcus faecalis (38%) were the main species detected. A further selection of potential probiotic starter cultures for fermented sausages focused on Lactobacillus as the most technologically relevant genus in this type of product. Lactobacilli strains were evaluated for their ability to grow in vitro in the processing conditions of fermented sausages and for their functional and safety properties, including antagonistic activity against foodborne pathogens, survival from gastrointestinal tract conditions (acidity, bile and pancreatin), tyramine production, antibiotic susceptibility and aggregation capacity. The best strains according to the results obtained were Lactobacillus casei/paracasei CTC1677, L. casei/paracasei CTC1678, Lactobacillus rhamnosus CTC1679, L. gasseri CTC1700, L. gasseri CTC1704, Lactobacillus fermentum CTC1693. Those strains were further assayed as starter cultures in model sausages. L. casei/paracasei CTC1677, L. casei/paracasei CTC1678 and L. rhamnosus CTC1679 were able to lead the fermentation and dominate (levels ca. 10(8) CFU/g) the endogenous lactic acid bacteria, confirming their suitability as probiotic starter cultures. Copyright © 2013 Elsevier Ltd. All rights reserved.

Selection of starter cultures for the production of sour cassava starch in a pilot-scale fermentation process.

PubMed

Penido, Fernanda Corrêa Leal; Piló, Fernanda Barbosa; Sandes, Sávio Henrique de Cicco; Nunes, Álvaro Cantini; Colen, Gecernir; Oliveira, Evelyn de Souza; Rosa, Carlos Augusto; Lacerda, Inayara Cristina Alves

2018-02-28

Sour cassava starch (Polvilho azedo) is obtained from a spontaneous fermentation conducted by microorganisms from raw materials and fermentation tanks. This product is traditionally used in the baking industry for the manufacture of biscuits and Brazilian cheese breads. However, the end of fermentation is evaluated empirically, and the process occurs without standardization, which results in products of inconsistent quality. Predominant microbiota from a cassava flour manufacturer was isolated in order to select starter cultures for the production of sour cassava starch in a pilot-scale fermentation process. Lactic acid bacteria and yeasts were isolated, enumerated and grouped by Restriction Fragment Length Polymorphism, and PCR fingerprinting, respectively. One isolate of each molecular profile was identified by sequencing of the rRNA gene. LAB were prevalent throughout the entire process. Lactobacillus brevis (21.5%), which produced the highest values of acidity, and Lactobacillus plantarum (13.9%) were among the most frequent species. Pichia scutulata (52.2%) was the prevalent yeast and showed amylolytic activity. The aforementioned species were tested as single and mixed starter cultures in a pilot-scale fermentation process for 28 days. L. plantarum exhibited better performance as a starter culture, which suggests its potential for the production of sour cassava starch. Copyright © 2018 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Preparation of a Lactobacillus plantarum starter culture for cucumber fermentations that can meet kosher guidelines

USDA-ARS?s Scientific Manuscript database

A method is described for growth of a Lactobacillus plantarum starter culture in jars of commercially available pasteurized fresh-pack kosher dill cucumbers so that jars can be used to inoculate commercial scale cucumber fermentation tanks. A procedure is also described to transfer lactic acid bacte...

The relationships between consumer liking, sensory and chemical attributes of Vitis vinifera L. cv. Pinotage wines elaborated with different Oenococcus oeni starter cultures.

PubMed

Malherbe, Sulette; Menichelli, Elena; du Toit, Maret; Tredoux, Andreas; Muller, Nina; Naes, Tormod; Nieuwoudt, Hélène

2013-08-30

Malolactic fermentation (MLF) mediated by lactic acid bacteria (LAB) has been shown to modulate chemical and sensory attributes of wine. This study investigated the relation between consumer liking, chemical and sensory attributes of Vitis vinifera L. cv. Pinotage wines that were made over two vintages by four different lactic acid Oenococcus oeni starter cultures as well as a control treatment where MLF was prevented. Descriptive analysis showed that the sensory attributes buttery, caramel, vegetative flavour, fruity and nutty aroma differed significantly between the wines. These effects on the wines were not the same for the two vintages tested. Preference mapping results showed that the sensory attributes influenced the average consumer liking. The main chemical and sensory correlations found for MLF-treated wines were related to 2,3-butanedione (diacetyl) with the buttery character and various esters with fruity aromas. Although the direct effect of the bacterial starter cultures on wine sensory attributes is difficult to establish, and subject to variation over vintage, the present work suggests that the contribution of LAB starter cultures to wine sensory attributes can influence consumer liking. Selection of an MLF starter culture can thus potentially be used to develop specific wine styles. © 2013 Society of Chemical Industry.

The role of lactic acid bacteria (Lactobacillus sp yel133) from beef in inhibiting of microbial contaminants on various fillers of starter culture

NASA Astrophysics Data System (ADS)

Yunilas; Mirwandhono, E.

2018-02-01

The role of Lactic Acid Bacteria (LAB) on the starter culture can be seen from the ability to grow and suppress the growth of microbial contaminants (fungi). The research aimed to investigate the role of LAB (Lactobacillus sp YEL133) in inhibiting microbial contaminants (fungi) on starter cultures of various fillers. The materials used in this research was Lactobacillus sp YEL133 from beef and various fillers (rice flour, corn starch and wheat flour). The research methods used completely randomized design (CRD) with 3 treatments and 4 replications. The treatments of this research was P1(rice flour), P2 (corn starch) and P3 (wheat flour) that inoculated with Lactobacillus sp YEL133. Parameters which is observed such as: growth of lactic acid bacteria, total microbes and total fungi as microbial contaminants. The results showed that the starter culture with a filler material of rice flour produce lactic acid bacteria and microbes were highly significant (P <0.01) for corn starch and wheat flour, as well as able to suppress the growth of microbial contaminants (fungi). The conclusion of the research is the use Lactobacillus sp YEL133 can suppress the growth of fungi on the starter culture using rice flour.

Relationships between functional genes in Lactobacillus delbrueckii ssp. bulgaricus isolates and phenotypic characteristics associated with fermentation time and flavor production in yogurt elucidated using multilocus sequence typing.

PubMed

Liu, Wenjun; Yu, Jie; Sun, Zhihong; Song, Yuqin; Wang, Xueni; Wang, Hongmei; Wuren, Tuoya; Zha, Musu; Menghe, Bilige; Heping, Zhang

2016-01-01

Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) is well known for its worldwide application in yogurt production. Flavor production and acid producing are considered as the most important characteristics for starter culture screening. To our knowledge this is the first study applying functional gene sequence multilocus sequence typing technology to predict the fermentation and flavor-producing characteristics of yogurt-producing bacteria. In the present study, phenotypic characteristics of 35 L. bulgaricus strains were quantified during the fermentation of milk to yogurt and during its subsequent storage; these included fermentation time, acidification rate, pH, titratable acidity, and flavor characteristics (acetaldehyde concentration). Furthermore, multilocus sequence typing analysis of 7 functional genes associated with fermentation time, acid production, and flavor formation was done to elucidate the phylogeny and genetic evolution of the same L. bulgaricus isolates. The results showed that strains significantly differed in fermentation time, acidification rate, and acetaldehyde production. Combining functional gene sequence analysis with phenotypic characteristics demonstrated that groups of strains established using genotype data were consistent with groups identified based on their phenotypic traits. This study has established an efficient and rapid molecular genotyping method to identify strains with good fermentation traits; this has the potential to replace time-consuming conventional methods based on direct measurement of phenotypic traits. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The production of glucans via glucansucrases from Lactobacillus satsumensis isolated from a fermented beverage starter culture

USDA-ARS?s Scientific Manuscript database

Several starter cultures used in the production of fermented beverages were screened for lactic acid bacteria that produced water-insoluble polysaccharides from sucrose. The strain producing the greatest amount was identified as Lactobacillus satsumensis by its 16S RNA sequence. This strain produc...

Enhancement of gamma-aminobutyric acid (GABA) levels using an autochthonous Lactobacillus futsaii CS3 as starter culture in Thai fermented shrimp (Kung-Som).

PubMed

Sanchart, Chatthaphisuth; Rattanaporn, Onnicha; Haltrich, Dietmar; Phukpattaranont, Pimpimol; Maneerat, Suppasil

2017-08-01

Gamma-aminobutyric acid (GABA) is a non-proteinogenic amino acid, which has a variety of well-characterized beneficial physiological functions. In order to improve GABA levels and the fermentation process of Thai fermented shrimp (Kung-Som), autochthonous Lactobacillus futsaii CS3 was inoculated as a starter culture into Kung-Som, and its effects on the quality of Kung-Som were studied. The optimal conditions for GABA production in Kung-Som as obtained by response surface methodology (RSM) using a central composite design (CCD) were an inoculum size of roughly 10 7 CFU/g (X 1 ) of L. futsaii cells together with the addition of 0.5% (w/w) monosodium glutamate (MSG) (X 2 ), resulting in maximum GABA levels of 10,500 mg per kg fresh product. Under these optimized conditions, the experimental GABA content of Kung-Som with an added starter culture was up to four times higher than that of the control (without starter culture) or commercial Kung-Som products (10,120 mg/kg product). Kung-Som produced by inoculation with L. futsaii CS3 but without addition of MSG showed a considerably increased GABA content of 7790 mg/kg compared to the control. Fermentation time was reduced to less than 1 week for these samples compared to the control batches, which took up to 19 days. Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) revealed that L. futsaii CS3 remained prominently throughout the Kung-Som fermentation, and that lactic acid bacteria (LAB) rapidly dominated the total microflora because of this inoculation with L. futsaii CS3. Kung-Som samples with starter culture were accepted as well as commercial ones by 30 panelists (p > 0.05). In conclusion, L. futsaii CS3 is a good starter culture for GABA production, resulting in, improved microbiological safety as well as reduced fermentation time.

Physicochemical and sensory characteristics of fat-free goat milk yogurt with added stabilizers and skim milk powder fortification.

PubMed

Bruzantin, F P; Daniel, J L P; da Silva, P P M; Spoto, M H F

2016-05-01

Goat milk yogurt has a less consistent coagulum compared with cow milk yogurt; furthermore, the presence of goat milk in foodstuffs imparts a characteristic flavor that can restrict its acceptance by consumers. This study aimed to assess and compare the physicochemical and sensory characteristics of fat-free goat milk yogurts with added stabilizers or bovine skim milk powder to improve the final product. Four treatment additions were evaluated: (1) a mixture of 0.1% (wt/vol) carrageenan and 0.1% (wt/vol) pectin (treatment CR); (2) 0.5% (wt/vol) pectin (treatment PE); (3) 4.65% (wt/vol) bovine skim milk powder (treatment BM); and (4) control (no stabilizer; treatment CT). The physicochemical parameters were investigated at on d 1 and 5 of storage. The BM treatment presented higher pH and titratable acidity values, resulting in a buffering capacity effect. The total crude protein (CP) and solids-not-fat (SNF) contents were also higher in BM compared with the other evaluated treatments because of the addition of bovine skim milk powder. We detected a reduction in pH values for all treatments. Lower SNF contents were present in the CR and CT treatments, which might be related to a syneresis process during storage; moreover, an increase in total CP was observed for all treatments due to the proteolytic action of the starter culture. Sensory attributes, including appearance (color, consistency, and presence of lumps), texture (consistency, viscosity, and presence of lumps), flavor (bitter, sweet, and characteristic of commercial plain nonfat yogurt), and overall impression were evaluated by quantitative descriptive analysis. The addition of 0.5% (wt/vol) of pectin (PE treatment) strengthened the curd; however, the visual and oral presence of lumps and a higher bitterness score were noted by trained panelists, which resulted in the lowest overall impression score for the PE treatment. In several sensory attributes, the CR treatment was considered similar to the control

Genome Sequence of Lactobacillus sakei subsp. sakei LS25, a Commercial Starter Culture Strain for Fermented Sausage.

PubMed

McLeod, Anette; Brede, Dag Anders; Rud, Ida; Axelsson, Lars

2013-07-11

Lactobacillus sakei is a lactic acid bacterium associated primarily with fermented meat and fish. Here, we present the draft genome sequence of L. sakei subsp. sakei strain LS25, a commercial starter culture strain for fermented sausage.

Effect of dissolved oxygen on redox potential and milk acidification by lactic acid bacteria isolated from a DL-starter culture.

PubMed

Larsen, Nadja; Werner, Birgit Brøsted; Vogensen, Finn Kvist; Jespersen, Lene

2015-03-01

Milk acidification by DL-starter cultures [cultures containing Lactococcus lactis diacetylactis (D) and Leuconostoc (L) species] depends on the oxidation-reduction (redox) potential in milk; however, the mechanisms behind this effect are not completely clear. The objective of this study was to investigate the effect of dissolved oxygen on acidification kinetics and redox potential during milk fermentation by lactic acid bacteria (LAB). Fermentations were conducted by single strains isolated from mixed DL-starter culture, including Lactococcus lactis ssp. lactis, Lactococcus lactis ssp. cremoris, and Leuconostoc mesenteroides ssp. cremoris, by the DL-starter culture, and by the type strains. High and low levels of oxygen were produced by flushing milk with oxygen or nitrogen, respectively. The kinetics of milk acidification was characterized by the maximum rate and time of acidification (Vamax and Tamax), the maximum rate and time of reduction (Vrmax and Trmax), the minimum redox potential (Eh7 final), and time of reaching Eh7 final (Trfinal). Variations in kinetic parameters were observed at both the species and strain levels. Two of the Lc. lactis ssp. lactis strains were not able to lower redox potential to negative values. Kinetic parameters of the DL-starter culture were comparable with the best acidifying and reducing strains, indicating their additive effects. Acidification curves were mostly diauxic at all oxygen levels, displaying 2 maxima of acidification rate: before (aerobic maximum) and after (anaerobic maximum) oxygen depletion. The redox potential decreased concurrently with oxygen consumption and continued to decrease at slower rate until reaching the final values, indicating involvement of both oxygen and microbiological activity in the redox state of milk. Oxygen flushing had a negative effect on reduction and acidification capacity of tested LAB. Reduction was significantly delayed at high initial oxygen, exhibiting longer Trmax, Trfinal, or both

How yogurt is processed

USDA-ARS?s Scientific Manuscript database

This month’s Processing column on the theme of “How Is It Processed?” focuses on yogurt. Yogurt is known for its health-promoting properties. This column will provide a brief overview of the history of yogurt and the current market. It will also unveil both traditional and modern yogurt processing t...

Microbiological characterization of traditional dough fermentation starter (Jiaozi) for steamed bread making by culture-dependent and culture-independent methods.

PubMed

Li, Zhijian; Li, Haifeng; Bian, Ke

2016-10-03

In this study, the microbial composition of two types of Jiaozi (a dough fermentation starter in making steamed bread) was investigated using both culture-dependent and culture-independent (PCR-DGGE) methods. The numbers of the cultivable bacteria on MRS at 30°C and yeast on YPD at 28°C in the maize flour Jiaozi (MFJ) were 9.21±0.16 Log CFU/g and 9.18±0.05 Log CFU/g, respectively, which were higher than that in the rice flour Jiaozi (RFJ) (P<0.05). A total of 140 bacteria and 124 yeasts were isolated and identified on the basis of the sequences of their 16S rRNA gene and ITS region. The culture-dependent method showed that Acetobacter tropicalis and Enterococcus durans were the predominant bacteria strains in MFJ, and accounted for 45.7% and 25.7% of the bacteria, and Lactobacillus plantarum and Pediococcus pentosaceus represented 12.8% and 8.6%. In the RFJ sample, the most prominent isolate was P. pentosaceus (38.6%), followed by L. plantarum (24.3%), A. tropicalis (22.8%), and E. durans (5.7%). P. pentosaceus and L. plantarum were also detected in both starters by PCR-DGGE, while some bacteria species such as A. tropicalis and E. durans, recovered as pure cultures, were not detected by direct PCR-DGGE. On the other hand, Lactobacillus brevis, Weissella sp. and Lactobacillus alimentarius detected by PCR-DGGE were not recovered in any of the media and conditions used. In the MFJ sample, the isolated main yeast species were identified as Wickerhamomyces anomalus (67.2%), Saccharomyces cerevisiae (27.9%) and Torulaspora delbrueckii (4.9%). In addition to S. cerevisiae (42.9%), W. anomalus (27.0%) and T. delbrueckii (7.9%), Saccharomycopsis fibuligera was also identified as the predominant isolate in RFJ samples and accounted for 22.2%. PCR-DGGE also indicated the presence of W. anomalus and S. cerevisiae in both MFJ and RFJ starters and S. fibuligera was also detected in RFJ, but T. delbrueckii was not detected in both samples. Copyright © 2016 Elsevier B.V. All

Rapid detection of bacteriophages in starter culture using water-in-oil-in-water emulsion microdroplets.

PubMed

Wang, Min S; Nitin, Nitin

2014-10-01

Bacteriophage contamination of starter culture and raw material poses a major problem in the fermentation industry. In this study, a rapid detection of lytic phage contamination in starter culture using water-in-oil-in-water (W/O/W) emulsion microdroplets was described. A model bacteria with varying concentrations of lytic phages were encapsulated in W/O/W emulsion microdroplets using a simple needle-in-tube setup. The detection of lytic phage contamination was accomplished in 1 h using the propidium iodide labeling of the phage-infected bacteria inside the W/O/W emulsion microdroplets. Using this approach, a detection limit of 10(2) PFU/mL of phages was achieved quantitatively, while 10(4) PFU/mL of phages could be detected qualitatively based on visual comparison of the fluorescence images. Given the simplicity and sensitivity of this approach, it is anticipated that this method can be adapted to any strains of bacteria and lytic phages that are commonly used for fermentation, and has potential for a rapid detection of lytic phage contamination in the fermentation industry.

Yogurt and weight management.

PubMed

Jacques, Paul F; Wang, Huifen

2014-05-01

A large body of observational studies and randomized controlled trials (RCTs) has examined the role of dairy products in weight loss and maintenance of healthy weight. Yogurt is a dairy product that is generally very similar to milk, but it also has some unique properties that may enhance its possible role in weight maintenance. This review summarizes the human RCT and prospective observational evidence on the relation of yogurt consumption to the management and maintenance of body weight and composition. The RCT evidence is limited to 2 small, short-term, energy-restricted trials. They both showed greater weight losses with yogurt interventions, but the difference between the yogurt intervention and the control diet was only significant in one of these trials. There are 5 prospective observational studies that have examined the association between yogurt and weight gain. The results of these studies are equivocal. Two of these studies reported that individuals with higher yogurt consumption gained less weight over time. One of these same studies also considered changes in waist circumference (WC) and showed that higher yogurt consumption was associated with smaller increases in WC. A third study was inconclusive because of low statistical power. A fourth study observed no association between changes in yogurt intake and weight gain, but the results suggested that those with the largest increases in yogurt intake during the study also had the highest increase in WC. The final study examined weight and WC change separately by sex and baseline weight status and showed benefits for both weight and WC changes for higher yogurt consumption in overweight men, but it also found that higher yogurt consumption in normal-weight women was associated with a greater increase in weight over follow-up. Potential underlying mechanisms for the action of yogurt on weight are briefly discussed.

Persistence of Escherichia coli O157:H7 in dairy fermentation systems.

PubMed

Dineen, S S; Takeuchi, K; Soudah, J E; Boor, K J

1998-12-01

We examined (i) the persistence of Escherichia coli O157:H7 as a postpasteurization contaminant in fermented dairy products; (ii) the ability of E. coli O157:H7 strains with and without the general stress regulatory protein, RpoS, to compete with commercial starter cultures in fermentation systems; and (iii) the survival of E. coli O157:H7 in the yogurt production process. In commercial products inoculated with 10(3) CFU/ml, E. coli O157:H7 was recovered for up to 12 days in yogurt (pH 4.0), 28 days in sour cream (pH 4.3), and at levels > 10(2) CFU/ml at 35 days in buttermilk (pH 4.1). For the starter culture competition trials, the relative inhibition of E. coli O157:H7 in the experimental fermentation systems was, in decreasing order, thermophilic culture mixture, Lactobacillus delbrueckii subsp. bulgaricus R110 alone, Lactococcus lactis subsp. lactis D280 alone, Lactococcus lactis subsp. cremoris D62 alone, and Streptococcus thermophilus C90 alone showing the least inhibition. Recovery of the rpoS mutant was lower than recovery of its wild-type parent by 72 h or earlier in the presence of individual starter cultures. No E. coli O157:H7 were recovered after the curd formation step in yogurt manufactured with milk inoculated with 10(5) CFU/ml. Our results show that (i) postprocessing entry of E. coli O157:H7 into fermented dairy products represents a potential health hazard; (ii) commercial starter cultures differ in their ability to reduce E. coli O157:H7 CFU numbers in fermentation systems; and (iii) the RpoS protein appears to most effectively contribute to bacterial survival in the presence of conditions that are moderately lethal to the cell.

Grana Padano cheese whey starters: microbial composition and strain distribution.

PubMed

Rossetti, Lia; Fornasari, Maria Emanuela; Gatti, Monica; Lazzi, Camilla; Neviani, Erasmo; Giraffa, Giorgio

2008-09-30

The aim of this work was to evaluate the species composition and the genotypic strain heterogeneity of dominant lactic acid bacteria (LAB) isolated from whey starter cultures used to manufacture Grana Padano cheese. Twenty-four Grana Padano cheese whey starters collected from dairies located over a wide geographic production area in the north of Italy were analyzed. Total thermophilic LAB streptococci and lactobacilli were quantified by agar plate counting. Population structure of the dominant and metabolically active LAB species present in the starters was profiled by reverse transcriptase, length heterogeneity-PCR (RT-LH-PCR), a culture-independent technique successfully applied to study whey starter ecosystems. The dominant bacterial species were Lactobacillus helveticus, Lactobacillus delbrueckii subsp. lactis, Streptococcus thermophilus, and Lactobacillus fermentum. Diversity in the species composition allowed the whey cultures to be grouped into four main typologies, the one containing L. helveticus, L. delbrueckii subsp. lactis, and S. thermophilus being the most frequent one (45% of the cultures analyzed), followed by that containing only the two lactobacilli (40%). Only a minor fraction of the cultures contained L. helveticus alone (4%) or all the four LAB species (11%). Five hundred and twelve strains were isolated from the 24 cultures and identified by M13-PCR fingerprinting coupled with 16S rRNA gene sequencing. Most of the strains were L. helveticus (190 strains; 37% of the total), L delbrueckii subsp. lactis (90 strains; 18%) and S. thermophilus (215 strains; 42%). This result was in good agreement with the qualitative whey starter composition observed by RT-LH-PCR. M13-PCR fingerprinting indicated a markedly low infra-species diversity, i.e. the same biotypes were often found in more than one culture. The distribution of the biotypes into the different cultures was mainly dairy plant-specific rather than correlated with the different production areas.

Yogurt and Cardiometabolic Diseases: A Critical Review of Potential Mechanisms.

PubMed

Fernandez, Melissa Anne; Panahi, Shirin; Daniel, Noémie; Tremblay, Angelo; Marette, André

2017-11-01

Associations between yogurt intake and risk of diet-related cardiometabolic diseases (CMDs) have been the subject of recent research in epidemiologic nutrition. A healthy dietary pattern has been identified as a pillar for the prevention of weight gain and CMDs. Epidemiologic studies suggest that yogurt consumption is linked to healthy dietary patterns, lifestyles, and reduced risk of CMDs, particularly type 2 diabetes. However, to our knowledge, few to no randomized controlled trials have investigated yogurt intake in relation to cardiometabolic clinical outcomes. Furthermore, there has been little attempt to clarify the mechanisms that underlie the potential beneficial effects of yogurt consumption on CMDs. Yogurt is a nutrient-dense dairy food and has been suggested to reduce weight gain and prevent CMDs by contributing to intakes of protein, calcium, bioactive lipids, and several other micronutrients. In addition, fermentation with bacterial strains generates bioactive peptides, resulting in a potentially greater beneficial effect of yogurt on metabolic health than nonfermented dairy products such as milk. To date, there is little concrete evidence that the mechanisms proposed in observational studies to explain positive results of yogurt on CMDs or parameters are valid. Many proposed mechanisms are based on assumptions that commercial yogurts contain strain-specific probiotics, that viable yogurt cultures are present in adequate quantities, and that yogurt provides a minimum threshold dose of nutrients or bioactive components capable of exerting a physiologic effect. Therefore, the primary objective of this review is to investigate the plausibility of potential mechanisms commonly cited in the literature in order to shed light on the inverse associations reported between yogurt intake and various cardiometabolic health parameters that are related to its nutrient profile, bacterial constituents, and food matrix. This article reviews current gaps and challenges

Influence of starter culture ratios and warm room treatment on free fatty acid and amino acid in Swiss cheese.

PubMed

Ji, T; Alvarez, V B; Harper, W J

2004-07-01

Quantification of water-soluble volatile free fatty acids (FFA) and free amino acids (FAA) was performed as a ripening index and an indirect measure of flavor development in Swiss-type cheeses. The objective of this research was to assess the effect of warm room treatment (WRT) and usage ratio of starter cultures, Streptococcus thermophilus and Lactobacillus helveticus vs. propionibacteria, on the concentration of FFA and FAA in pilot plant-scale Swiss cheese. A capillary gas chromatograph equipped with a flame ionization detector was used for the analysis of FFA in Swiss cheese. Free amino acids were analyzed by the Cd-ninhydrin method. Starter culture ratios did not affect development of FAA during the cheese ripening. However, duration of WRT had an effect on the concentration of FAA in the Swiss cheese. Free amino acids increased considerably during WRT. A continuous increase in FAA was shown during 70-d ripening time after WRT. The concentrations of C2:0 and C3:0 fatty acids were affected by starter culture ratios after 2-wk WRT, but these differences had mostly disappeared after 3-wk WRT. Similar concentrations of FFA and FAA reported in previous studies were developed in Swiss cheese with a 3-wk WRT and a 0.33:1 ratio of Streptococcus thermophilus and Lactobacillus helveticus to propionibacteria.

Viability and growth promotion of starter and probiotic bacteria in yogurt supplemented with whey protein hydrolysate during refrigerated storage.

PubMed

Dąbrowska, Anna; Babij, Konrad; Szołtysik, Marek; Chrzanowska, Józefa

2017-11-22

The effect of whey protein hydrolysate (WPH) addition on growth of standard yoghurt cultures and Bifidobacterium adolescentis during co-fermentation and its viability during storage at 4ºC in yoghurts has been evaluated. WPH was obtained with the use of serine protease from Y. lipolytica yeast. Stirred probiotic yoghurts were prepared by using whole milk standardized to 16% of dry matter with the addition of either whey protein concentrate, skim milk powder (SMP), WPH-SMP (ratio 1:1), WPH. The hydrolysate increased the yoghurt culture counts at the initial stage of fermentation and significantly inhibited the decrease in population viability throughout the storage at 4ºC in comparison to the control. The post-fermentation acidification was also retarded by the addition of WPH. The hydrolysate did not increase the Bifidobacterium adolescentis counts at the initial stage. However, the WPH significantly improved its viability. After 21 days of storage, in the yogurts supplemented with WPH, the population of these bacteria oscillated around 3.04 log10 CFU/g, while in samples where SMP or whey protein concentrate was used, the bacteria were no longer detected.

Starter culture development for improving safety and quality of Domiati cheese.

PubMed

Ayad, Eman H E

2009-08-01

Eleven lactococci strains (sp. lactis and cremoris) were collected according to specific or selected characteristics for development of defined strain starter (DSS) to improve safety and nutritional quality of traditional and low salt Domiati cheese. Thirteen DSS; nisin-producing system or/and folate-producing strains were prepared. The behaviour of the strains in DSS was studied in milk and in two series of Domiati cheese; the first one made with 5% NaCl and salt tolerant strains, the second made with 3% NaCl and the control cheeses were made without starters. The population dynamics of strains and sensory evaluation of cheese corroborated the results in milk. All strains can grow well together and appeared to produce pleasant flavours, normal (typical) body and texture Domiati cheese. There was no apparent difference in cheese composition between cheeses in each series; the levels were within margins for composition of Domiati cheese. The levels of nisin (IU g(-1)) ranged from 204 to 324 IU g(-1) in 3-months' cheeses. Folate concentration increased in cheeses made with DSS cultures than control and the level ranged from 5.5 to 11.1 microg 100 g(-1) in cheeses after 3 months. All results revealed that selected DSS can be used for improving Domiati cheese.

Cultivability of Streptococcus thermophilus in Grana Padano cheese whey starters.

PubMed

Fornasari, Maria Emanuela; Rossetti, Lia; Carminati, Domenico; Giraffa, Giorgio

2006-04-01

The application of a culture-independent approach, that of reverse transcriptase-length heterogeneity-PCR coupled with epifluorescence microscopy, allowed us to observe that Streptococcus thermophilus is metabolically active, but only partially cultivable in Grana Padano cheese whey starters. A short preincubation of the starters in sterile skimmed whey was followed by cultivation in sterile skimmed whey-enriched M17. This procedure restored the cultivability of S. thermophilus and enabled us to detect S. thermophilus at ranges (10(7)-10(8) CFU mL(-1)) which have rarely been reported in these cultures. The use of cheese whey as a cultivation-revitalization substrate can be useful to obtain an unbiased picture of the microbial composition of whey starters for Grana Padano cheese, thus avoiding an underestimation of S. thermophilus in these cultures.

Assessment of Characteristics and Functional Properties of Lactobacillus Species Isolated from Kimchi for Dairy Use

PubMed Central

Baick, Seung-Chun

2015-01-01

The objective of this study was to identify lactic acid bacteria (LAB) isolated from kimchi and to evaluate its characteristics and functional properties for application in fermented dairy products as a probiotic or commercial starter culture. Eight stains isolated from kimchi were selected through an investigation of phenotypic characteristics. Two strains (DK211 and DK303) were identified as Lactobacillus plantarum, another two (DK207 and DK215) as Lactobacillus paracasei, and one (DK301) as Lactobacillus sakei. The remaining three strains were identified as species of Weissella. All selected Lactobacillus strains had acid and bile tolerance, even though there was wide variation in the ability of each strain. DK303 showed a remarkably higher proteolytic activity. There were no significant differences in β-galactosidase activity among the tested strains, except that DK301 showed no activity. Auto-aggregation varied between 82.1 and 90.0%, and hydrophobicity values ranged from 0.5 to 51.6%.The strongest auto-aggregation and hydrophobicity were observed in DK211. All selected strains showed better 1,1-diphenyl-2-picrylhydrzyl (DPPH) scavenging activity than commercial strains. DK211, DK215, DK301, and DK303 had effective inhibitory activity against all pathogens tested except E. coli. When selected strains were used for yogurt preparation as a single starter culture, the time required to reach target titratable acidity (0.9) was 11-12 h. The yogurt fermented with DK211 had favorable panelists ratings for most sensory attributes, which were comparable with yogurt fermented with a commercial strain. The results suggest that strains isolated from kimchi could be potential probiotic and starter cultures for use in yogurt manufacturing. PMID:26761848

Lactose digestion from flavored and frozen yogurts, ice milk, and ice cream by lactase-deficient persons.

PubMed

Martini, M C; Smith, D E; Savaiano, D A

1987-10-01

Lactose digestion from and tolerance to flavored and frozen yogurts, ice cream, and ice milk were evaluated (20 g lactose/meal) in lactase-deficient subjects by use of breath hydrogen techniques. Unflavored yogurt caused significantly less hydrogen production than milk (37 vs 185 delta ppm X h, n = 9). Flavored yogurt was intermediate (77 delta ppm X h). Subjects were free of symptoms after consuming flavored and unflavored yogurts. Of seven commercial yogurts tested, all contained significant levels of microbial beta-galactosidase (beta-gal). In addition, eight subjects were fed meals of milk, ice milk, ice cream, and frozen yogurts with and without cultures containing high levels of beta-gal. Peak hydrogen excretion after consumption of frozen yogurt with high beta-gal was less than one-half of that observed after the other five test meals and intolerance symptoms were absent. Tolerance to frozen yogurt, produced under usual commercial procedures, was found to be similar to that of ice milk and ice cream.

Characterization of Bacteria in Nigerian Yogurt as Promising Alternative to Antibiotics in Gastrointestinal Infections.

PubMed

Ayeni, Anthony Opeyemi; Ruppitsch, Werner; Ayeni, Funmilola Abidemi

2018-03-14

Gastrointestinal infections are endemic in Nigeria and several factors contribute to their continual survival, including bacterial resistance to commonly used antibiotics. Nigerian yogurts do not include probiotics, and limited information is available about the antimicrobial properties of the fermenters in the yogurt against gastrointestinal pathogens. Therefore, the antimicrobial potentials of bacteria in Nigeria-produced yogurts against intestinal pathogens were investigated in this study. Viable counts of lactic acid bacteria (LAB) in 15 brands of yogurt were enumerated and the bacteria identified by partial sequencing of 16S rRNA gene. Susceptibility of the gastrointestinal pathogens (Salmonella, Shigella and E. coli ) to antibiotics by disc diffusion method, to viable LAB by the agar overlay method, and to the cell-free culture supernatant (CFCS) of the LAB were investigated. Co-culture analysis of LAB and pathogens were also done. Viable counts of 1.5 × 10 11 cfu/ml were observed in some yogurt samples. Two genera were identified: Lactobacillus (70.7%) and Acetobacter (29.3%). The Lactobacillus species reduced multidrug-resistant gastrointestinal pathogens by 4 to 5 log while the zones of inhibition ranged between 11 and 23. The Lactobacillus and Acetobacter strains examined displayed good activities against the multidrug-resistant tested pathogens. This is the first report of antimicrobial activities of acetic acid bacteria isolated from yogurt in Nigeria.

Effect of sugar and acid on the acceptability of frozen yogurt to a student population.

PubMed

Guinard, J X; Little, C; Marty, C; Palchak, T R

1994-05-01

One hundred and forty-one college students tasted and rated on a nine-point hedonic scale their degree of liking for nine samples of vanilla frozen yogurt varying in sugar and lactic acid. Subjects were also asked to complete a questionnaire about consumption of frozen yogurt and other dairy products. Degree of liking differed significantly among samples, and the samples best liked were those with the lowest acidity, .23 to .29%, independent of sugar concentration. Degree of liking of frozen yogurt failed to correlate with dairy product consumption or hunger at the time of testing. No significant difference existed between male and female students for overall degree of liking of frozen yogurt or overall dairy product intake, yet the questionnaire revealed a significantly higher consumption of frozen yogurt among female students. The results of this study suggest that, for the student population tested, frozen yogurt should combine the sensory properties of ice cream (low acidity) with the nutritional properties of yogurt (low fat, active enzyme culture).

Spray-dried adjunct cultures of autochthonous non-starter lactic acid bacteria.

PubMed

Peralta, Guillermo H; Bergamini, Carina V; Audero, Gabriela; Páez, Roxana; Wolf, I Verónica; Perotti, M Cristina; Hynes, Erica R

2017-08-16

Spray-drying of lactic cultures provides direct-to-vat starters, which facilitate their commercialization and use. However, this process may alter the metabolic activity and deteriorate technological features. In this work, we assessed the influence of spray-drying on the survival and aroma production of two strains of mesophilic lactobacilli: Lactobacillus paracasei 90 and Lactobacillus plantarum 91, which have already been characterized as good adjunct cultures. The spray-drying was carried out using a laboratory scale spray and the dried cultures were monitored during the storage for the survival rate. The dried cultures were applied to two cheese models: sterile cheese extract and miniature soft cheese. The influence on the carbohydrate metabolism and the production of organic acids and volatile compounds was determined. Both strains retained high levels of viable counts in the powder after drying and during the storage at 5°C for twelve months. In addition, they also remained at high level in both cheese models during incubation or ripening. Similar profiles of carbohydrate fermentation and bioformation of volatile compounds were observed in the cheese extracts for each of the strains when tested as both fresh and dried cultures. In addition, the ability of Lb. paracasei 90 to increase the production of acetoin and diacetyl remarkably in cheese models was also confirmed for the spray-dried culture. Copyright © 2017 Elsevier B.V. All rights reserved.

How is an ideal satiating yogurt described? A case study with added-protein yogurts.

PubMed

Morell, P; Piqueras-Fiszman, B; Hernando, I; Fiszman, S

2015-12-01

Protein is recognized as the macronutrient with the highest satiating ability. Yogurt can be an excellent basis for designing satiating food as it is protein-based food product. Five different set-type yogurts were formulated by adding extra skim milk powder (MP), whey protein concentrate (WPC), calcium caseinate (CAS) or a blend of whey protein concentrate with calcium caseinate (CAS-WPC). A control yogurt without extra protein content was also prepared. Differences in sensory perceptions (through CATA questions) were related to the consumers' expected satiating ability and liking scores (of several modalities). In addition, an "Ideal satiating yogurt" was included in the CATA question to perform a penalty analysis to show potential directions for yogurt reformulation and to relate sensory and non-sensory yogurt characteristics to satiating capacity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Starter Culture Selection for Making Chinese Sesame-Flavored Liquor Based on Microbial Metabolic Activity in Mixed-Culture Fermentation

PubMed Central

Wu, Qun; Ling, Jie

2014-01-01

Selection of a starter culture with excellent viability and metabolic activity is important for inoculated fermentation of traditional food. To obtain a suitable starter culture for making Chinese sesame-flavored liquor, the yeast and bacterium community structures were investigated during spontaneous and solid-state fermentations of this type of liquor. Five dominant species in spontaneous fermentation were identified: Saccharomyces cerevisiae, Pichia membranaefaciens, Issatchenkia orientalis, Bacillus licheniformis, and Bacillus amyloliquefaciens. The metabolic activity of each species in mixed and inoculated fermentations of liquor was investigated in 14 different cocultures that used different combinations of these species. The relationships between the microbial species and volatile metabolites were analyzed by partial least-squares (PLS) regression analysis. We found that S. cerevisiae was positively correlated to nonanal, and B. licheniformis was positively associated with 2,3-butanediol, isobutyric acid, guaiacol, and 4-vinyl guaiacol, while I. orientalis was positively correlated to butyric acid, isovaleric acid, hexanoic acid, and 2,3-butanediol. These three species are excellent flavor producers for Chinese liquor. Although P. membranaefaciens and B. amyloliquefaciens were not efficient flavor producers, the addition of them alleviated competition among the other three species and altered their growth rates and flavor production. As a result, the coculture of all five dominant species produced the largest amount of flavor compounds. The result indicates that flavor producers and microbial interaction regulators are important for inoculated fermentation of Chinese sesame-flavored liquor. PMID:24814798

Quantification of viable bacterial starter cultures of Virgibacillus sp. and Tetragenococcus halophilus in fish sauce fermentation by real-time quantitative PCR.

PubMed

Udomsil, Natteewan; Chen, Shu; Rodtong, Sureelak; Yongsawatdigul, Jirawat

2016-08-01

Real-time quantitative polymerase chain reaction (qPCR) methods were developed for the quantification of Virgibacillus sp. SK37 and Tetragenococcus halophilus MS33, which were added as starter cultures in fish sauce fermentation. The PCR assays were coupled with propidium monoazide (PMA) treatment of samples to selectively quantify viable cells and integrated with exogenous recombinant Escherichia coli cells to control variabilities in analysis procedures. The qPCR methods showed species-specificity for both Virgibacillus halodenitrificans and T. halophilus as evaluated using 6 reference strains and 28 strains of bacteria isolated from fish sauce fermentation. The qPCR efficiencies were 101.1% for V. halodenitrificans and 90.2% for T. halophilus. The quantification limits of the assays were 10(3) CFU/mL and 10(2) CFU/mL in fish sauce samples with linear correlations over 4 Logs for V. halodenitrificans and T. halophilus, respectively. The matrix effect was not observed when evaluated using fish sauce samples fermented for 1-6 months. The developed PMA-qPCR methods were successfully applied to monitor changes of Virgibacillus sp. SK37 and T. halophilus MS33 in a mackerel fish sauce fermentation model where culture-dependent techniques failed to quantify the starter cultures. The results demonstrated the usability of the methods as practical tools for monitoring the starter cultures in fish sauce fermentation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Erosive and buffering capacities of yogurt.

PubMed

Kargul, Betul; Caglar, Esber; Lussi, Adrian

2007-05-01

The capability of drinks and foods to resist pH changes brought about by salivary buffering may play an important role in the erosion of dental enamel. The aim of the present study was to measure the initial pH of several types of yogurt and to test the degrees of saturation (pK-pl) with respect to hydroxyapatite and fluorapatite to determine the buffering capacity and related erosive potential of yogurt. Twenty-five milliliters of 7 types of freshly opened yogurt was titrated with 1 mol/L of sodium hydroxide, added in 0.5 mL increments, until the pH reached 10, to assess the total titratable acidity, a measure of the drink's own buffering capacity. The degrees of saturation (pK-pl) with respect to hydroxyapatite and fluorapatite were also calculated, using a computer program developed for this purpose. For statistical analysis, samples were compared using Kruskal-Wallis test. The buffering capacities can be ordered as follows: fruit yogurt >low-fat yogurt >bioyogurt >butter yogurt >natural yogurt >light fruit yogurt >light yogurt. The results suggest that, in vitro, fruit yogurt has the greatest buffering capacity. It can be stated that it is not possible to induce erosion on enamel with any type of yogurt.

Competitiveness and antibacterial potential of bacteriocin-producing starter cultures in different types of fermented sausages.

PubMed

Ravyts, Frédéric; Barbuti, Silvana; Frustoli, Maria Angela; Parolari, Giovanni; Saccani, Giovanna; De Vuyst, Luc; Leroy, Frédéric

2008-09-01

Application of bacteriocin-producing starter cultures of lactic acid bacteria in fermented sausage production contributes to food safety. This is sometimes hampered by limited efficacy in situ and by uncertainty about strain dependency and universal applicability for different sausage types. In the present study, a promising antilisterial-bacteriocin producer, Lactobacillus sakei CTC 494, was applied as a coculture in addition to commercial fermentative starters in different types of dry-fermented sausages. The strain was successful in both Belgian-type sausage and Italian salami that were artificially contaminated with about 3.5 log CFU g(-1) of Listeria monocytogenes. After completion of the production process, this led to listerial reductions of up to 1.4 and 0.6 log CFU g(-1), respectively. In a control sausage, containing only the commercial fermentative starter, the reduction was limited to 0.8 log CFU g(-1) for the Belgian-type recipe, where pH decreased from 5.9 to 4.9, whereas an increase of 0.2 log CFU g(-1) was observed for Italian salami, in which the pH rose from 5.7 to 5.9 after an initial decrease to pH 5.3. In a Cacciatore recipe inoculated with 5.5 log CFU g(-1) of L. monocytogenes and in the presence of L. sakei CTC 494, there was a listerial reduction of 1.8 log CFU g(-1) at the end of the production process. This was superior to the effect obtained with the control sausage (0.8 log CFU g(-1)). Two commercial antilisterial cultures yielded reductions of 1.2 and 1.5 log CFU g(-1). Moreover, repetitive DNA sequence-based PCR fingerprinting demonstrated the competitive superiority of L. sakei CTC 494.

Biodiversity among Lactobacillus helveticus Strains Isolated from Different Natural Whey Starter Cultures as Revealed by Classification Trees

PubMed Central

Gatti, Monica; Trivisano, Carlo; Fabrizi, Enrico; Neviani, Erasmo; Gardini, Fausto

2004-01-01

Lactobacillus helveticus is a homofermentative thermophilic lactic acid bacterium used extensively for manufacturing Swiss type and aged Italian cheese. In this study, the phenotypic and genotypic diversity of strains isolated from different natural dairy starter cultures used for Grana Padano, Parmigiano Reggiano, and Provolone cheeses was investigated by a classification tree technique. A data set was used that consists of 119 L. helveticus strains, each of which was studied for its physiological characters, as well as surface protein profiles and hybridization with a species-specific DNA probe. The methodology employed in this work allowed the strains to be grouped into terminal nodes without difficult and subjective interpretation. In particular, good discrimination was obtained between L. helveticus strains isolated, respectively, from Grana Padano and from Provolone natural whey starter cultures. The method used in this work allowed identification of the main characteristics that permit discrimination of biotypes. In order to understand what kind of genes could code for phenotypes of technological relevance, evidence that specific DNA sequences are present only in particular biotypes may be of great interest. PMID:14711641

The substitution of a traditional starter culture in mutton fermented sausages by Lactobacillus acidophilus and Bifidobacterium animalis.

PubMed

Holko, I; Hrabě, J; Šalaková, A; Rada, V

2013-07-01

Common starter cultures used in fermented mutton sausages were substituted by probiotic strains of Lactobacillus acidophilus CCDM 476 and Bifidobacterium animalis 241a. Technological properties of the traditional and the probiotic sausages were compared. The potential probiotic effect was evaluated by enumeration of bifidobacteria and lactobacilli in stool samples of 15 volunteers before and after a 14-day consumption period. The numbers of lactobacilli (10(7) cfu/g) and bifidobacteria (10(3) cfu/g) in the final product did not affect the technological properties. The use of L. acidophilus as a starter culture was found more beneficial than the use of B. animalis. Even after 60 days of storage, high counts of L. acidophilus (10(6) cfu/g) were detected; on the other hand, the counts of B. animalis were under the detection limit. Regarding sensory properties, the probiotic products showed better texture, and, curiously, a reduction of the typical smell of mutton. The numbers of lactobacilli in stool samples increased significantly after the consumption of the probiotic sausages. Copyright © 2013 Elsevier Ltd. All rights reserved.

Fastener Starter

NASA Technical Reports Server (NTRS)

Chandler, Faith; Garton, Harry; Valentino, Bill; Amett, Mike

2005-01-01

The Fastener Starter is a creative solution to prevent the loss of small fasteners during their installation. This is the only currently available tool that can firmly grip and hold a single screw, bolt, nut, washer, spacer, or any combination of these parts. Other commercially available fastener starters are unable to accommodate a variety of parts simultaneously. The Fastener Starter is a more capable and easier tool to use than prior tools. Its compact size allows it to be used effectively in cramped, difficult-to-see locations. Its design also allows it to be used with or without handles and extenders in other difficult-to-reach locations. It provides better protection against cross threading and loss of fasteners and associated parts. The Fastener Starter is non-magnetic and does not off-gas, thus meeting flight hardware requirements. The Fastener Starter incorporates a combination of features of several commercially available tools, providing an improved means of installing small fasteners. The Fastener Starter includes a custom molded insert that can be removed easily and replaced with a conventional tool bit (e.g., a screwdriver or hex-driver bit). When used with the insert, the Fastener Starter prevents cross threading and damage to internal threaded holes. This is achieved by allowing the fastener to slip within the tool insert when used without a conventional tool bit. Alternatively, without the insert and with a tool bit, the Fastener Starter can torque a fastener. The Fastener Starter has a square recess hole that accepts a conventional square drive handle or extension to accommodate a variety of applications by providing flexibility in handle style and length.

Optimization of Culture Medium for the Growth of Candida sp. and Blastobotrys sp. as Starter Culture in Fermentation of Cocoa Beans (Theobroma cacao) Using Response Surface Methodology (RSM).

PubMed

Mahazar, N H; Zakuan, Z; Norhayati, H; MeorHussin, A S; Rukayadi, Y

2017-01-01

Inoculation of starter culture in cocoa bean fermentation produces consistent, predictable and high quality of fermented cocoa beans. It is important to produce healthy inoculum in cocoa bean fermentation for better fermented products. Inoculum could minimize the length of the lag phase in fermentation. The purpose of this study was to optimize the component of culture medium for the maximum cultivation of Candida sp. and Blastobotrys sp. Molasses and yeast extract were chosen as medium composition and Response Surface Methodology (RSM) was then employed to optimize the molasses and yeast extract. Maximum growth of Candida sp. (7.63 log CFU mL-1) and Blastobotrys sp. (8.30 log CFU mL-1) were obtained from the fermentation. Optimum culture media for the growth of Candida sp., consist of 10% (w/v) molasses and 2% (w/v) yeast extract, while for Blastobotrys sp., were 1.94% (w/v) molasses and 2% (w/v) yeast extract. This study shows that culture medium consists of molasses and yeast extract were able to produce maximum growth of Candida sp. and Blastobotrys sp., as a starter culture for cocoa bean fermentation.

The effect of non-standard heat treatment of sheep's milk on physico-chemical properties, sensory characteristics, and the bacterial viability of classical and probiotic yogurt.

PubMed

Zamberlin, Šimun; Samaržija, Dubravka

2017-06-15

Classical and probiotic set yogurt were made using non-standard heat treatment of sheep's milk at 60°C/5min. Physico-chemical properties, sensory characteristics, and the viability of bacteria that originated from cultures in classical and probiotic yogurt were analysed during 21days of storage at 4°C. For the production of yogurt, a standard yogurt culture and a probiotic strain Lactobacillus rhamnosus GG were used. At the end of storage time of the classical and probiotic yogurt the totals of non-denatured whey proteins were 92.31 and 91.03%. The viability of yogurt culture bacteria and Lactobacillus rhamnosus GG were higher than 10 6 cfu/g. The total sensory score (maximum - 20) was 18.49 for the classical and 18.53 for the probiotic. In nutritional and functional terms it is possible to produce classical and probiotic sheep's milk yogurt by using a non-standard temperature of heat treatment with a shelf life of 21days. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acceptance of sugar reduction in flavored yogurt.

PubMed

Chollet, M; Gille, D; Schmid, A; Walther, B; Piccinali, P

2013-09-01

To investigate what level of sugar reduction is accepted in flavored yogurt, we conducted a hedonic test focusing on the degree of liking of the products and on optimal sweetness and aroma levels. For both flavorings (strawberry and coffee), consumers preferred yogurt containing 10% added sugar. However, yogurt containing 7% added sugar was also acceptable. On the just-about-right scale, yogurt containing 10% sugar was more often described as too sweet compared with yogurt containing 7% sugar. On the other hand, the sweetness and aroma intensity for yogurt containing 5% sugar was judged as too low. A second test was conducted to determine the effect of flavoring concentration on the acceptance of yogurt containing 7% sugar. Yogurts containing the highest concentrations of flavoring (11% strawberry, 0.75% coffee) were less appreciated. Additionally, the largest percentage of consumers perceived these yogurts as "not sweet enough." These results indicate that consumers would accept flavored yogurts with 7% added sugar instead of 10%, but 5% sugar would be too low. Additionally, an increase in flavor concentration is undesirable for yogurt containing 7% added sugar. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Enhanced natural killer cell activation by exopolysaccharides derived from yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1.

PubMed

Makino, Seiya; Sato, Asako; Goto, Ayako; Nakamura, Marie; Ogawa, Miho; Chiba, Yoshika; Hemmi, Jun; Kano, Hiroshi; Takeda, Kazuyoshi; Okumura, Ko; Asami, Yukio

2016-02-01

Yogurt is generally recognized as a beneficial food for our health, but research into its physiological effects has focused mainly on intestinal dysfunctions such as constipation and diarrhea. We previously found yogurt fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 (hereafter OLL1073R-1) could reduce risks of catching the common cold and flu in human trials. It was assumed that immunostimulatory exopolysaccharide (EPS) produced from OLL1073R-1 play an important role in this context. However, few studies have examined the immunostimulatory effects of traditional Bulgarian yogurts fermented with different strains of lactobacilli and their metabolites. Therefore, we screened 139 L. delbrueckii ssp. bulgaricus strains and identified OLL1073R-1 as the most robust producer of EPS. This strain was also the only strain that induced the production of IFN-γ in vitro. Oral administration of the EPS or yogurt fermented with OLL1073R-1 and Streptococcus thermophilus OLS3059 (OLL1073R-1 yogurt) augmented natural killer (NK) cell activity and induced IFN-γ production in spleen cells in mice, whereas 2 other yogurts fermented with other strains had no effect on NK cell activity. Cellular preparations of the OLL1073R-1 strain also slightly augmented NK cell activity, but were less effective than EPS itself. The EPS-dependent stimulation of NK cell activity was abrogated in IFN-γ knockout mice and in myeloid differentiation factor 88 knockout mice. Furthermore, IFN-γ production from spleen cells stimulated with EPS was completely blocked with both anti-IL-12 and anti-IL-18 antibodies in vitro. These findings suggest that NK cell activation by OLL1073R-1 yogurt is EPS-dependent, occurs via IL-12- and IL-18-mediated IFN-γ production, and requires myeloid differentiation factor 88. We showed that traditional Bulgarian yogurt could exert immunostimulatory effects by selecting starter strains and part of the mechanisms depend on IFN-γ inducible EPS produced

Yogurt protects against growth retardation in weanling rats fed diets high in phytic acid

PubMed Central

Gaetke, Lisa M.; McClain, Craig J.; Toleman, C. Jean; Stuart, Mary A.

2010-01-01

The purpose of this study was to determine the affects of adding yogurt to animal diets which were high in phytic acid (PA) and adequate in zinc (38 μg Zn/g). The PA:Zn molar ratio was 60:1. Zinc status was determined by documenting growth and measuring the zinc concentration in bone (tibia) and plasma. For 25 days, 6 groups (n=6) of Sprague-Dawley weanling rats were fed one of the following AIN-76 diets. Half of the diets contained PA. Four of the diets contained yogurt with either active or heat-treated (inactive) cultures added at 25% of the diet. Diets: (without PA) 1) AIN, 2) AIN with active yogurt, 3) AIN and inactive yogurt; and (with PA) 4) AIN with PA, 5) AIN with PA plus active yogurt, and 6) AIN with PA plus inactive yogurt. Body weight, weight gain, and zinc concentration in bone and plasma were measured, and feed efficiency ratio (FER) was calculated. Rats fed diets with PA and yogurt had normal growth compared to the control group. Growth retardation was evident in the group fed the diet with PA and no yogurt. This group had significantly lower body weight compared to all other groups (p<0.05). Rats fed diets with PA, with or without yogurt, had significantly lower zinc concentration in bone and plasma (p<0.05). Adding yogurt to diets high in PA resulted in normal growth in weanling rats, however, zinc concentration in bone and plasma was still sub-optimal. PMID:19269152

Rhinocerebral Mucor circinelloides infection in immunocompromised patient following yogurt ingestion.

PubMed

Lazar, Stephen P; Lukaszewicz, Jennifer M; Persad, Kamleish A; Reinhardt, John F

2014-08-01

The purpose of this case report is to illustrate the cause of this patient's headache and sinus pain in the setting of a unique environmental exposure: the patient ingested yogurt only days before presentation. This particular brand of yogurt caused controversy in early September 2013 when the manufacturer voluntarily recalled all flavors. The yogurt was found to be contaminated with Mucor circinelloides. The recall was triggered by the FDA, after receiving many complaints from consumers affected by temporary gastrointestinal symptoms such as abdominal cramping, diarrhea, and nausea. This patient was diagnosed with Rhinocerebral mucormycosis through fungal culture of the affected area. He was specifically colonized with Mucor circinelloides, a variant that rarely causes disease in humans. According to a literature review, only eight cases of mucormycosis in adults caused by this strain were documented before 2009.

Impact of a Microbial Cocktail Used as a Starter Culture on Cocoa Fermentation and Chocolate Flavor.

PubMed

Magalhães da Veiga Moreira, Igor; de Figueiredo Vilela, Leonardo; da Cruz Pedroso Miguel, Maria Gabriela; Santos, Cledir; Lima, Nelson; Freitas Schwan, Rosane

2017-05-09

Chocolate production suffered a vast impact with the emergence of the "witches' broom" disease in cocoa plants. To recover cocoa production, many disease-resistant hybrid plants have been developed. However, some different cocoa hybrids produce cocoa beans that generate chocolate with variable quality. Fermentation of cocoa beans is a microbiological process that can be applied for the production of chocolate flavor precursors, leading to overcoming the problem of variable chocolate quality. The aim of this work was to use a cocktail of microorganisms as a starter culture on the fermentation of the ripe cocoa pods from PH15 cocoa hybrid, and evaluate its influence on the microbial communities present on the fermentative process on the compounds involved during the fermentation, and to perform the chocolate sensorial characterization. According to the results obtained, different volatile compounds were identified in fermented beans and in the chocolate produced. Bitterness was the dominant taste found in non-inoculated chocolate, while chocolate made with inoculated beans showed bitter, sweet, and cocoa tastes. 2,3-Butanediol and 2,3-dimethylpyrazine were considered as volatile compounds making the difference on the flavor of both chocolates. Saccharomyces cerevisiae UFLA CCMA 0200, Lactobacillus plantarum CCMA 0238, and Acetobacter pasteurianus CCMA 0241 are proposed as starter cultures for cocoa fermentation.

Lipolytic Changes in Fermented Sausages Produced with Turkey Meat: Effects of Starter Culture and Heat Treatment

PubMed Central

Kolsarici, Nuray; Candoğan, Kezban

2014-01-01

In this study, the effects of two different commercial starter culture mixes and processing methodologies (traditional and heat process) on the lipolytic changes of fermented sausages manufactured with turkey meat were evaluated during processing stages and storage. Free fatty acid (FFA) value increased with fermentation and during storage over 120 d in all fermented sausage groups produced with both processing methodologies (p<0.05). After drying stage, free fatty acid values of traditional style and heat processed fermented sausages were between 10.54-13.01% and 6.56-8.49%, respectively. Thiobarbituric acid (TBA) values of traditionally processed fermented sausages were between 0.220-0.450 mg·kg-1, and TBA values of heat processed fermented sausages were in a range of 0.405-0.795 mg·kg-1. Oleic and linoleic acids were predominant fatty acids in all fermented sausages. It was seen that fermented sausage groups produced with starter culture had lower TBA and FFA values in comparison with the control groups, and heat application inhibited the lipase enzyme activity and had an improving effect on lipid oxidation. As a result of these effects, heat processed fermented sausages had lower FFA and higher TBA values than the traditionally processed groups. PMID:26760744

Lipolytic Changes in Fermented Sausages Produced with Turkey Meat: Effects of Starter Culture and Heat Treatment.

PubMed

Karsloğlu, Betül; Çiçek, Ümran Ensoy; Kolsarici, Nuray; Candoğan, Kezban

2014-01-01

In this study, the effects of two different commercial starter culture mixes and processing methodologies (traditional and heat process) on the lipolytic changes of fermented sausages manufactured with turkey meat were evaluated during processing stages and storage. Free fatty acid (FFA) value increased with fermentation and during storage over 120 d in all fermented sausage groups produced with both processing methodologies (p<0.05). After drying stage, free fatty acid values of traditional style and heat processed fermented sausages were between 10.54-13.01% and 6.56-8.49%, respectively. Thiobarbituric acid (TBA) values of traditionally processed fermented sausages were between 0.220-0.450 mg·kg(-1), and TBA values of heat processed fermented sausages were in a range of 0.405-0.795 mg·kg(-1). Oleic and linoleic acids were predominant fatty acids in all fermented sausages. It was seen that fermented sausage groups produced with starter culture had lower TBA and FFA values in comparison with the control groups, and heat application inhibited the lipase enzyme activity and had an improving effect on lipid oxidation. As a result of these effects, heat processed fermented sausages had lower FFA and higher TBA values than the traditionally processed groups.

The Use of Lactic Acid Bacteria Starter Cultures during the Processing of Fermented Cereal-based Foods in West Africa: A Review.

PubMed

Soro-Yao, Amenan Anastasie; Brou, Kouakou; Amani, Georges; Thonart, Philippe; Djè, Koffi Marcelin

2014-12-01

Lactic acid bacteria (LAB) are the primary microorganisms used to ferment maize-, sorghum- or millet-based foods that are processed in West Africa. Fermentation contributes to desirable changes in taste, flavour, acidity, digestibility and texture in gruels (ogi, baca, dalaki), doughs (agidi, banku, komé) or steam-cooked granulated products (arraw, ciacry, dégué). Similar to other fermented cereal foods that are available in Africa, these products suffer from inconsistent quality. The use of LAB starter cultures during cereal dough fermentation is a subject of increasing interest in efforts to standardise this step and guaranty product uniformity. However, their use by small-scale processing units or small agro-food industrial enterprises is still limited. This review aims to illustrate and discuss major issues that influence the use of LAB starter cultures during the processing of fermented cereal foods in West Africa.

Lactose digestion from yogurt: mechanism and relevance.

PubMed

Savaiano, Dennis A

2014-05-01

Yogurt is traditionally consumed throughout the world among populations who are seemingly unable to digest lactose. This review provides a historical overview of the studies that show lactose digestion and tolerance from yogurt by lactose-intolerant people. The lactose in yogurt is digested more efficiently than other dairy sources of lactose because the bacteria inherent in yogurt assist with its digestion. The bacterial lactase survives the acidic conditions of the stomach, apparently being physically protected within the bacterial cells and facilitated by the buffering capacity of yogurt. The increasing pH as the yogurt enters the small intestine and a slower gastrointestinal transit time allow the bacterial lactase to be active, digesting lactose from yogurt sufficiently to prevent symptoms in lactose-intolerant people. There is little difference in the lactase capability of different commercial yogurts, because they apparently contain Lactobacillus bulgaricus and Streptococcus thermophilus in sufficient quantities (10(8) bacteria/mL). However, Lactobacillus acidophilus appears to require cell membrane disruption to physically release the lactase. Compared with unflavored yogurts, flavored yogurts appear to exhibit somewhat reduced lactase activity but are still well tolerated.

Viability of bifidobacteria strains in yogurt with added oat beta-glucan and corn starch during cold storage.

PubMed

Rosburg, Valerie; Boylston, Terri; White, Pamela

2010-06-01

Probiotics must be consumed at a level of 10(7) CFU/mL for successful colonization of the gut. In yogurts containing beneficial cultures, the survival of probiotic strains can quickly decline below this critical concentration during cold storage. We hypothesized that beta-glucan would increase the viability of bifidobacteria strains in yogurt during cold storage. Yogurts were produced containing 0.44% beta-glucan (concentrated or freeze-dried) extracted from whole oat flour and/or 1.33% modified corn starch, and bifidobacteria (B. breve or B. longum) at a concentration of at least 10(9) CFU/mL. All yogurts were stored at 4 degrees C. Bifidobacteria and yogurt cultures, Streptococcus thermophilus and Lactobacillus delbureckii subsp. bulgaricus, were enumerated from undisturbed aliquots before fermentation, after fermentation, and once a week for 5 wk. S. thermophilus and L. bulgaricus maintained a concentration of at least 10(8) CFU/mL in yogurts containing concentrated or freeze-dried beta-glucan regardless of starch addition, and in the control with no added beta-glucan or starch. Similarly, the probiotic, Bifidobacterium breve, survived above a therapeutic level in all treatments. The addition of beta-glucan prolonged the survival of Bifidobacterium longum at a concentration of at least 10(7) CFU/mL by up to 2 wk on average beyond the control. Further, the inclusion of concentrated beta-glucan in yogurt improved survival of B. longum above 10(7) CFU/mL by 1 wk longer than did freeze-dried beta-glucan. Study results suggest that beta-glucan has a protective effect on bifidobacteria in yogurt when stressed by low-temperature storage.

Starter/generator testing

NASA Astrophysics Data System (ADS)

Anon

1994-10-01

Sundstrand Aerospace and GE Aircraft Engines have studied the switched reluctance machine for use as an integral starter/generator for future aircraft engines. They have conducted an initial, low-power testing of the starter/generator, which is based on power inverters using IGBT-technology semiconductors, to verify its feasibility in the externally mounted version of the integral starter/generator. This preliminary testing of the 250-kW starter/generator reveals favorable results.

Volatile flavor compounds in yogurt: a review.

PubMed

Cheng, Hefa

2010-11-01

Considerable knowledge has been accumulated on the volatile compounds contributing to the aroma and flavor of yogurt. This review outlines the production of the major flavor compounds in yogurt fermentation and the analysis techniques, both instrumental and sensory, for quantifying the volatile compounds in yogurt. The volatile compounds that have been identified in plain yogurt are summarized, with the few key aroma compounds described in detail. Most flavor compounds in yogurt are produced from lipolysis of milkfat and microbiological transformations of lactose and citrate. More than 100 volatiles, including carbonyl compounds, alcohols, acids, esters, hydrocarbons, aromatic compounds, sulfur-containing compounds, and heterocyclic compounds, are found in yogurt at low to trace concentrations. Besides lactic acid, acetaldehyde, diacetyl, acetoin, acetone, and 2-butanone contribute most to the typical aroma and flavor of yogurt. Extended storage of yogurt causes off-flavor development, which is mainly attributed to the production of undesired aldehydes and fatty acids during lipid oxidation. Further work on studying the volatile flavor compounds-matrix interactions, flavor release mechanisms, and the synergistic effect of flavor compounds, and on correlating the sensory properties of yogurt with the compositions of volatile flavor compounds are needed to fully elucidate yogurt aroma and flavor.

Yogurt Is a Low-Glycemic Index Food.

PubMed

Wolever, Thomas Ms

2017-07-01

High yogurt intake is associated with a reduced risk of type 2 diabetes (T2DM). Although several mechanisms could explain this association, this paper addresses the glycemic and insulinemic impact of yogurt. There is evidence that low-glycemic index (GI) and low-glycemic load (GL) diets are associated with a reduced risk of T2DM. The 93 GI values for yogurt in the University of Sydney's GI database have a mean ± SD of 34 ± 13, and 92% of the yogurts are low-GI (≤55). The 43 plain yogurts in the database have a lower GI than the 50 sweetened yogurts, 27 ± 11 compared with 41 ± 11 ( P < 0.0001). This difference is not explained by sugar, per se, but rather by the higher protein-to-carbohydrate ratio in plain yogurt. Although yogurt has a low GI, its insulinemic index (II) is higher than its GI. High insulin responses may be deleterious because hyperinsulinemia is associated with an increased risk of T2DM. Nevertheless, this may not be a concern for yogurt because, although its II is higher than its GI, the II of yogurt is within the range of II values for nondairy low-GI foods. In addition, mixed meals containing dairy protein elicit insulin responses similar to those elicited by mixed meals of similar composition containing nondairy protein. Because the GI of yogurt is lower than that of most other carbohydrate foods, exchanging yogurt for other protein and carbohydrate sources can reduce the GI and GL of the diet, and is in line with recommended dietary patterns, which include whole grains, fruits, vegetables, nuts, legumes, fish, vegetable oils, and yogurt. © 2017 American Society for Nutrition.

Potential Health Benefits of Combining Yogurt and Fruits Based on Their Probiotic and Prebiotic Properties.

PubMed

Fernandez, Melissa Anne; Marette, André

2017-01-01

Fruit and yogurt have been identified individually as indicators of healthy dietary patterns. Fruits are relatively low in energy density and are an excellent source of antioxidants and prebiotic fibers and polyphenols, which can promote digestive health. Yogurt, on the other hand, is a nutrient-dense food that is a good source of dairy protein, calcium, magnesium, vitamin B-12, conjugated linoleic acid, and other key fatty acids. In addition, it contains beneficial bacterial cultures, making it a potential source of probiotics. Yogurt's unique fermented food matrix provides added health benefits by enhancing nutrient absorption and digestion. Combining the intake of yogurt and fruit could provide probiotics, prebiotics, high-quality protein, important fatty acids, and a mixture of vitamins and minerals that have the potential to exert synergistic effects on health. Yogurt consumption has been associated with reduced weight gain and a lower incidence of type 2 diabetes, whereas fruits have established effects on reducing the risk of cardiovascular disease. Yogurt and fruits can be eaten together and may exert combined health benefits through potential prebiotic and probiotic effects. Furthermore, substituting high-energy, nutrient-deficient snacks with fruit and yogurt could reduce the intake of high-calorie obesogenic foods. In light of the positive cardiometabolic impacts of fruit and yogurt and their association with healthy dietary patterns, there is sufficient evidence to warrant further exploration into the potential synergistic health benefits of a combined intake of fruit and yogurt. © 2017 American Society for Nutrition.

The Use of Lactic Acid Bacteria Starter Cultures during the Processing of Fermented Cereal-based Foods in West Africa: A Review

PubMed Central

Soro-Yao, Amenan Anastasie; Brou, Kouakou; Amani, Georges; Thonart, Philippe; Djè, Koffi Marcelin

2014-01-01

Lactic acid bacteria (LAB) are the primary microorganisms used to ferment maize-, sorghum- or millet-based foods that are processed in West Africa. Fermentation contributes to desirable changes in taste, flavour, acidity, digestibility and texture in gruels (ogi, baca, dalaki), doughs (agidi, banku, komé) or steam-cooked granulated products (arraw, ciacry, dégué). Similar to other fermented cereal foods that are available in Africa, these products suffer from inconsistent quality. The use of LAB starter cultures during cereal dough fermentation is a subject of increasing interest in efforts to standardise this step and guaranty product uniformity. However, their use by small-scale processing units or small agro-food industrial enterprises is still limited. This review aims to illustrate and discuss major issues that influence the use of LAB starter cultures during the processing of fermented cereal foods in West Africa. PMID:27073601

Evaluation of the use of malic acid decarboxylase-deficient starter culture in NaCl-free cucumber fermentations to reduce bloater incidence

USDA-ARS?s Scientific Manuscript database

AIMS: Accumulation of carbon dioxide in cucumber fermentations is known to cause hollow cavities inside whole fruits or bloaters, conducive to economic losses for the pickling industry. This study focused on evaluating the use of a malic acid decarboxylase (MDC)-deficient starter culture to minimiz...

Influence of oregano essential oil on traditional Argentinean cheese elaboration: Effect on lactic starter cultures.

PubMed

Marcial, Guillermo E; Gerez, Carla L; de Kairuz, Martha Nuñez; Araoz, Victoria Coll; Schuff, Carola; de Valdez, Graciela Font

The aim of this work is to study the oregano essential oil (OEO) composition from Northwestern Argentinean regions and to evaluate its effect on the lactic starter cultures. The oregano used, Origanum vulgare var hirtum, was obtained from Andalgalá, Catamarca. The essential oil presented high amounts of α-terpinene (10%), γ-terpinene (15.1%), terpinen-4-ol (15.5%) and thymol (13.0%) as the main components. No negative effect on growth or metabolic activity of lactic acid bacteria Streptococcus thermophilus CRL 728 and CRL 813, Lactobacillus delbrueckii subsp. bulgaricus CRL 656 and CRL 468, and Lactococcus lactis subsp. lactis CRL 597 up to the maximum concentration (200μg/g) assayed was observed. No differences in the organoleptic characteristics of semi-hard cheeses flavored with oregano essential oil (200μg/g) and homemade cheeses flavored with oregano leaves were found. With respect to the microbiological quality of the products, neither enterobacteria nor mold and yeast were detected during ripening in essential-oil flavored cheese compared to control cheese (enterobacteria 2×10 3 UFC/g) and cheese flavored with oregano leaves (mold/yeast 4×10 4 CFU/g). Our results showed that the use of oregano essential oil and lactic starter culture considerably improved cheese quality. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Yogurt: role in healthy and active aging.

PubMed

El-Abbadi, Naglaa Hani; Dao, Maria Carlota; Meydani, Simin Nikbin

2014-05-01

Yogurt consumption has been associated with health benefits in different populations. Limited information, however, is available on nutritional and health attributes of yogurt in older adults. Yogurt is abundant in calcium, zinc, B vitamins, and probiotics; it is a good source of protein; and it may be supplemented with vitamin D and additional probiotics associated with positive health outcomes. Aging is accompanied by a wide array of nutritional deficiencies and health complications associated with under- and overnutrition, including musculoskeletal impairment, immunosenescence, cardiometabolic diseases, and cognitive impairment. Furthermore, yogurt is accessible and convenient to consume by the older population, which makes yogurt consumption a feasible approach to enhance older adults' nutritional status. A limited number of studies have specifically addressed the impact of yogurt on the nutritional and health status of older adults, and most are observational. However, those reported thus far and reviewed here are encouraging and suggest that yogurt could play a role in improving the nutritional status and health of older adults. In addition, these reports support further investigation into the role of yogurt in healthy and active aging.

Antibacterial and antiproliferative peptides in synbiotic yogurt-Release and stability during refrigerated storage.

PubMed

Sah, B N P; Vasiljevic, T; McKechnie, S; Donkor, O N

2016-06-01

The search for alternative therapeutics is on the rise due to the extensive increase in bacterial resistance to various conventional antibiotics and side effects of conventional cancer therapies. Bioactive peptides released from natural sources such as dairy foods by lactic acid bacteria have received attention as a potential source of biotherapeutic peptides. However, liberation of peptides in yogurt depends on proteolytic activities of the cultures used. Thus, this research was conducted to establish generation of inhibitory peptides in yogurt against pathogenic bacteria and cancer cells during storage at 4°C for 28d. Water-soluble crude peptide extracts were prepared by high-speed centrifugation of plain and probiotic yogurts supplemented with or without pineapple peel powder (PPP). The inhibition zones against Escherichia coli and Staphylococcus aureus by PPP-fortified probiotic yogurt at 28d of storage were, respectively, 25.89 and 11.72mm in diameter, significantly higher than that of nonsupplemented control yogurts. Antiproliferative activity against HT29 colon cancer cells was also significantly higher in probiotic yogurt with PPP than in nonsupplemented probiotic yogurt. Overall, crude water-soluble peptide extracts of the probiotic yogurt with PPP possessed stronger inhibitory activities against bacteria and cancer cells than controls, and these activities were maintained during storage. However, activities were lowered substantially during in vitro gastrointestinal digestion. These findings support the possibility of utilizing dairy-derived bioactive peptides in the development of a superior alternative to the current generation of antibacterial and anticancer agents, as well as a functional ingredient in foods, nutraceuticals, and pharmaceuticals. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Monitoring of Leuconostoc mesenteroides DRC starter in fermented vegetable by random integration of chloramphenicol acetyltransferase gene.

PubMed

Eom, Hyun-Ju; Park, Joong Min; Seo, Min Jae; Kim, Myoung-Dong; Han, Nam Soo

2008-09-01

In 2004, Leuconostoc mesenteroides DRC was first used as a starter culture for achieving higher organoleptic effects in Korean kimchi manufacture. For a better understanding of starter growth in a mixed culture system, and for predicting starter predominance in kimchi, a monitoring system for the starter was established. The chloramphenicol resistance marker gene (cat) was randomly integrated into chromosomal DNA of L. mesenteroides DRC using a viral transposon and transposase. The DRC mutant, tDRC2, had a similar growth pattern to the host strain, with no major alteration in phenotypic characteristics. The mutant strain was inoculated into real kimchi, and monitoring of the starter population was successfully achieved. The overall predominance of Leuconostoc in kimchi inoculated with DRC followed the general growth pattern of this genus during kimchi fermentation. Our results also demonstrate the competitive ability of the DRC starter against Leuconostoc from natural flora, maintaining its predominance above 88% during the whole fermentation period. Based on this experiment, the random gene integration method using a transposon was shown to be of utility in transferring any commercial starter into a selectable and monitorable strain for simulation purposes.

Manufacture and characterization of a yogurt-like beverage made with oat flakes fermented by selected lactic acid bacteria.

PubMed

Luana, Nionelli; Rossana, Coda; Curiel, José Antonio; Kaisa, Poutanen; Marco, Gobbetti; Rizzello, Carlo Giuseppe

2014-08-18

This study aimed at investigating the suitability of oat flakes for making functional beverages. Different technological options were assayed, including the amount of flakes, the inoculum of the starter and the addition of enzyme preparations. The beverage containing 25% (wt/wt) of oat flakes and fermented with L. plantarum LP09 was considered optimal on the basis of sensory and technological properties. The enzyme addition favored the growth of the starter, shortened the time needed to reach pH4.2 to ca. 8h, and favored a decrease of the quotient of fermentation. Fermentation increased the polyphenols availability and the antioxidant activity (25 and 70% higher, respectively) and decreased the hydrolysis index in vitro. Sensory analyses showed that fermented oat flakes beverage had the typical features of a yogurt-like beverage, enhancing the overall intensity of odor and flavor compared to the non-fermented control. Selection of proper processing and fermentation condition allowed the obtainment of a beverage with better nutritional and sensory properties. Copyright © 2014 Elsevier B.V. All rights reserved.

Yogurt's flexible image during its rise in popularity in post-war Belgium.

PubMed

Verriet, Jon; Leroy, Frédéric

2017-01-01

The consumption of yogurt in Western countries has risen for over a century, first slowly, then more rapidly. The purpose of the present study was to investigate this prolonged phase of growth, by examining the popularity and the projected image of yogurt. A particular focus was on the way these aspects were reflected in consumption patterns and media representations. The data showed how during its period of rapid popularization, yogurt's visibility in the media greatly increased. It was concluded that the product's image was highly flexible in post-war decades, evidenced by the multi-pronged approach taken by marketers. Yogurt was not only advertised as both tasty and healthy, but also as natural and convenient, a strategy that appears to have been informed by consumers' preferences and existing cultural values. This demonstrates how a high degree of product differentiation and diversification during a product's growth stage can result in a heterogeneous image, allowing for a broad range of marketing strategies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Introduction to the yogurt in nutrition initiative and the First Global Summit on the health effects of yogurt.

PubMed

Donovan, Sharon M; Shamir, Raanan

2014-05-01

Yogurt has been part of the human diet for thousands of years, and during that time a number of health benefits have been associated with its consumption. The goal of the First Global Summit on the Health Effects of Yogurt was to review and evaluate the strength of current scientific knowledge with regard to the health benefits of yogurt and to identify areas where further research is needed. The evidence base for the benefits of yogurt in promoting bone health, maintaining health throughout the life cycle, improving diet quality, and reducing the incidence of chronic diseases, such as obesity, metabolic syndrome, and cardiovascular disease, was presented. When assessing a complex food matrix, rather than specific nutrients, scientists and consumers are faced with new challenges as to how a food item's quality or necessity would be judged as part of an individual's whole diet. To tackle this challenge, speakers described methods for assessing the nutrient density of foods and its application to yogurt, use of yogurt for lactose intolerance, and the cost-effectiveness of yogurt and dairy products in reducing health care expenses. Last, speakers described the role of dairy products in global public health and nutrition, the scientific basis for current dairy recommendations, and future scientific and policy needs related to dairy and yogurt recommendations.

Track Starter's Guide.

ERIC Educational Resources Information Center

Dailey, Charles H.; Rankin, Kelly D.

This guide was developed to serve both the novice and experienced starter in track and field events. Each year in the United States, runners encounter dozens of different starters' mannerisms as they travel to track meets in various towns and states. The goal of any competent and conscientious starter is to insure that all runners receive a fair…

Probiotic Strawberry Yogurts: Microbiological, Chemical and Sensory Properties.

PubMed

Turgut, Tamer; Cakmakci, Songül

2018-03-01

This study was performed to determine the viability of Lactobacillus acidophilus and Bifidobacterium bifidum in yogurt made with strawberry marmalade (SM) and to examine the quality properties of probiotic yogurt. Acidity, pH, bacterial counts and sensory analysis of the yogurt samples were investigated on days 1, 3, 5, 7, 10 and 14 during storage at 4 °C. The survival rate of L. acidophilus was greater than that of B. bifidum. The viability of L. acidophilus decreased during the storage period, but B. bifidum numbers remained stable during the storage period. The highest L. acidophilus count (7.20 log cfu/g) was found in L. acidophilus + B. bifidum SM yogurt on day 1. The highest B. bifidum count (6.13 log cfu/g) was detected in yogurt containing L. acidophilus + B. bifidum SM yogurt on day 7. Yeast and mould counts of all yogurts increased during the storage period. Coliform bacteria and Staphylococcus aureus were not detected in the yogurt samples. The highest overall acceptance sensory score was observed in yogurts containing L. acidophilus. Considering the sensory and probiotic characteristics of all yogurt samples, this study suggested that strawberry yogurt with a suitable 5-7 day storage period can be produced with single L. acidophilus addition or single B. bifidum addition.

Monitoring of staphylococcal starters in two French processing plants manufacturing dry fermented sausages.

PubMed

Corbiere Morot-Bizot, S; Leroy, S; Talon, R

2007-01-01

The growth and survival of Staphylococcus xylosus and Staphylococcus carnosus were monitored during sausage manufacture in two processing plants. The gram-positive, catalase-positive cocci isolated from the processing plants F10 and F11 were identified by Staphylococcus-specific PCR and species-specific oligonucleotide array. In the inoculated products with starter cultures, 90% of staphylococcal strains isolated in F10 were identified as S. xylosus and 10% as S. carnosus. In F11, 77% were identified as S. xylosus and 20% as S. carnosus. Staphylococcus xylosus dominated the staphylococcal microbiota while S. carnosus survived during the process. The pulse-field gel electrophoresis analysis revealed that all S. xylosus and S. carnosus strains isolated corresponded to the starter strains inoculated. The two starter strains of S. xylosus co-dominated in the isolates from sausages of F11, whereas the strain with pattern A1 was dominant in the isolates from sausages of F10. In the environments, no S. carnosus and S. xylosus were found, whereas Staphylococcus equorum and Staphylococcus saprophyticus were the main species isolated. This work highlighted the domination of S. xylosus starter strains, which showed a strong capacity to grow during sausage process, while S. carnosus survived during the process. Successful implantation of starter cultures is obviously a prerequisite for their contribution to sensorial qualities. Thus, the monitoring of the growth and the survival of S. xylosus and S. carnosus are required to guarantee a well-adapted starter culture. This study revealed that the two Staphylococcus species are suitable for manufacturing sausages in processing plants with very different capacities of production.

Fortification of yogurt with oat hydrocolloid

USDA-ARS?s Scientific Manuscript database

C-Trim 30, an oat hydrocolloid was added to milk such that fermented yogurt had 0, 0.75, 1.5, 2.25, and 3 g ß-glucan per serving. The fermentation rate and physical characteristics of yogurt were studied. Lactose fermentation was not inhibited by the addition of C-Trim. All yogurt mix reached the...

Yogurt and Diabetes: Overview of Recent Observational Studies.

PubMed

Salas-Salvadó, Jordi; Guasch-Ferré, Marta; Díaz-López, Andrés; Babio, Nancy

2017-07-01

The effects of dairy consumption on the prevention of type 2 diabetes remain controversial and depend on the dairy subtype. Yogurt intake has received special attention because its association with health benefits is more consistent than that of other types of dairy products. In the present article, we review those observational studies that evaluated the association between yogurt consumption and type 2 diabetes. We also discuss the possible mechanisms involved in these associations. We found that 13 prospective studies evaluated the association between yogurt intake and type 2 diabetes, most of which showed an inverse association between the frequency of yogurt consumption and the risk of diabetes. In addition to the scientific evidence accumulated from individual prospective studies, several meta-analyses have shown that yogurt consumption has a potential role in diabetes prevention. The most recent analysis shows a 14% lower risk of type 2 diabetes when yogurt consumption was 80-125 g/d compared with no yogurt consumption. The intake of fermented dairy products, especially yogurt, has been inversely associated with variables of glucose metabolism. Yogurt may have probiotic effects that could modulate glucose metabolism. We conclude that yogurt consumption, in the context of a healthy dietary pattern, may reduce the risk of type 2 diabetes in healthy and older adults at high cardiovascular risk. Large-scale intervention studies and randomized clinical trials are warranted to determine if yogurt consumption has beneficial effects on insulin sensitivity and reduces the risk of type 2 diabetes. © 2017 American Society for Nutrition.

Characterization of Active Dry Wine Yeast During Starter Culture (Pied de Cuve) Preparation for Sparkling Wine Production.

PubMed

Benucci, Ilaria; Liburdi, Katia; Cerreti, Martina; Esti, Marco

2016-08-01

The preparation of yeast starter culture (Pied de Cuve) for producing sparkling wine with the traditional method is a key factor for manufacturing a good Prise de mousse. In this paper, the evolution of total yeast population, its viability during Pied de Cuve preparation, and the pressure profile during the 2nd fermentation in 2 different base wines made from Bombino bianco and Chardonnay grapes were investigated using 4 different commercial active dried yeasts. The study proves that despite the initial differences observed throughout the acclimatization phase, all the tested strains showed similar results on either the total population (from 8.2 × 10(7) cells/mL to 1.3 × 10(8) cells/mL) or cellular viability (from 70% to 84%). Independently from the base wine tested, the kinetic of sugar consumption was faster during the gradual acclimatization to the alcoholic medium (phase II) and slower during the preparation of starter culture in active growth phase (phase III). During both of these phases Saccharomyces cerevisiae bayanus Vitilevure DV10(®) (Station œnotechnique de Champagne) proved to have a higher sugar consumption rate than the other strains. During the Prise de mousse, S. cerevisiae bayanus Lalvin EC-1118(®) (Lallemand) reached the maximum pressure increase within time in both base wines. © 2016 Institute of Food Technologists®

Potential Health Benefits of Combining Yogurt and Fruits Based on Their Probiotic and Prebiotic Properties123

PubMed Central

2017-01-01

Fruit and yogurt have been identified individually as indicators of healthy dietary patterns. Fruits are relatively low in energy density and are an excellent source of antioxidants and prebiotic fibers and polyphenols, which can promote digestive health. Yogurt, on the other hand, is a nutrient-dense food that is a good source of dairy protein, calcium, magnesium, vitamin B-12, conjugated linoleic acid, and other key fatty acids. In addition, it contains beneficial bacterial cultures, making it a potential source of probiotics. Yogurt’s unique fermented food matrix provides added health benefits by enhancing nutrient absorption and digestion. Combining the intake of yogurt and fruit could provide probiotics, prebiotics, high-quality protein, important fatty acids, and a mixture of vitamins and minerals that have the potential to exert synergistic effects on health. Yogurt consumption has been associated with reduced weight gain and a lower incidence of type 2 diabetes, whereas fruits have established effects on reducing the risk of cardiovascular disease. Yogurt and fruits can be eaten together and may exert combined health benefits through potential prebiotic and probiotic effects. Furthermore, substituting high-energy, nutrient-deficient snacks with fruit and yogurt could reduce the intake of high-calorie obesogenic foods. In light of the positive cardiometabolic impacts of fruit and yogurt and their association with healthy dietary patterns, there is sufficient evidence to warrant further exploration into the potential synergistic health benefits of a combined intake of fruit and yogurt. PMID:28096139

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

Lactobacillus sakei: A Starter for Sausage Fermentation, a Protective Culture for Meat Products

PubMed Central

Zagorec, Monique; Champomier-Vergès, Marie-Christine

2017-01-01

Among lactic acid bacteria of meat products, Lactobacillus sakei is certainly the most studied species due to its role in the fermentation of sausage and its prevalence during cold storage of raw meat products. Consequently, the physiology of this bacterium regarding functions involved in growth, survival, and metabolism during meat storage and processing are well known. This species exhibits a wide genomic diversity that can be observed when studying different strains and on which probably rely its multiple facets in meat products: starter, spoiler, or protective culture. The emerging exploration of the microbial ecology of meat products also revealed the multiplicity of bacterial interactions L. sakei has to face and their various consequences on microbial quality and safety at the end of storage. PMID:28878171

Amylose-potassium oleate inclusion complex in plain set-style yogurt.

PubMed

Singh, Mukti; Byars, Jeffrey A; Kenar, James A

2014-05-01

Health and wellness aspirations of U.S. consumers continue to drive the demand for lower fat from inherently beneficial foods such as yogurt. Removing fat from yogurt negatively affects the gel strength, texture, syneresis, and storage of yogurt. Amylose-potassium oleate inclusion complexes (AIC) were used to replace skim milk solids to improve the quality of nonfat yogurt. The effect of AIC on fermentation of yogurt mix and strength of yogurt gel was studied and compared to full-fat samples. Texture, storage modulus, and syneresis of yogurt were observed over 4 weeks of storage at 4 °C. Yogurt mixes having the skim milk solids partially replaced by AIC fermented at a similar rate as yogurt samples with no milk solids replaced and full-fat milk. Initial viscosity was higher for yogurt mixes with AIC. The presence of 3% AIC strengthened the yogurt gel as indicated by texture and rheology measurements. Yogurt samples with 3% AIC maintained the gel strength during storage and resulted in low syneresis after storage for 4 wk. © 2014 Institute of Food Technologists®

Yogurt: role in healthy and active aging

USDA-ARS?s Scientific Manuscript database

Yogurt consumption has been associated with health benefits in different populations. Limited information, however, is available on nutritional and health attributes of yogurt in older adults. Yogurt is abundant in calcium, zinc, B vitamins, and probiotics, it is a good source of protein, and it ma...

Yogurt, diet quality and lifestyle factors.

PubMed

Panahi, S; Fernandez, M A; Marette, A; Tremblay, A

2017-05-01

Yogurt consumption has been associated with healthy dietary patterns and lifestyles, better diet quality and healthier metabolic profiles. Studies have shown that frequent yogurt consumers do not only have higher nutrient intakes, but also an improved diet quality, which includes higher consumption of fruits and vegetables, whole grains, and dairy compared with low or non-consumers indicating better compliance with dietary guidelines. Recent epidemiological and clinical evidence suggests that yogurt contributes to better metabolic health because of its effects on the control of body weight, energy homeostasis and glycemic control. Furthermore, yogurt consumers have been shown to be more physically active (⩾ 2 h/week), smoke less, have higher education and knowledge of nutrition compared with non-consumers. Thus, yogurt consumption may be considered a signature of a healthy diet through its nutritional content, impact on metabolic health including the control of energy balance, body weight and glycemia and its relationships with healthier behaviors and lifestyle factors.

Designing Inquiry Starters

NASA Astrophysics Data System (ADS)

Kluger-Bell, B.

2010-12-01

The term "Inquiry Starter" comes from the Institute for Inquiry's model for teaching and learning science through inquiry. It refers to the first phase of an inquiry activity where learners engage in actions that stimulate their curiosity and generate questions for further investigation. In the Professional Development Program, staff and participants have designed a wide variety of inquiry activities with a number of variations on the inquiry starter. This has provided a laboratory for examining inquiry starter design. In this paper, I describe and examine in detail the elements of this design and how the design of those elements is related to achieving learning objectives. There are a number of important common objectives in all inquiry starters. For example, all starters must define a domain for investigation and engage the learner's curiosity in that domain. There are also critical differences in learning objectives depending on the content area being studied, the learners' background knowledge and skills, and many other factors. In this paper I examine designs for both of these types of objectives.

Probiotic Yogurt Culture Bifidobacterium Animalis Subsp. Lactis BB-12 and Lactobacillus Acidophilus LA-5 Modulate the Cytokine Secretion by Peripheral Blood Mononuclear Cells from Patients with Ulcerative Colitis.

PubMed

Sheikhi, A; Shakerian, M; Giti, H; Baghaeifar, M; Jafarzadeh, A; Ghaed, V; Heibor, M R; Baharifar, N; Dadafarin, Z; Bashirpour, G

2016-06-01

There are some evidences for the immunomodulation disorders in the response to intestinal microbiota in inflammatory bowel disease. Yogurt is a fermented milk product made with a starter culture consisting of different probiotics which could be colonized in intestine. However, the role of probiotics in the aetiopathogenesis of ulcerative colitis (UC) has not been clarified. To determine how the immune system responds to these bacteria this study was planned. Bifidobacterium lactis BB-12 (B. lactis) and Lactobacillus acidophilus LA-5 (L. acidophilus) were cultivated on MRS broth. PBMCs of 36 UC patients were separated by Ficoll-Hypaque centrifugation and co-cultured with different concentrations of UV killed bacteria in RPMI-1 640 plus 10% FCS for 48/72 h. IL-10, TGF-β, IFN-γ and TNF-α were measured in supernatant of PBMCs by ELISA. Both bacteria significantly augmented IL-10, TGF-β, IFN-γ and TNF-α compared to control (p<0.001). The secretion levels of IL-10 and TGF-β by B. lactis- compared to L. acidophilus-stimulated PBMCs were significantly higher (p<0.05, p<0.01 respectively). The secretion levels of TNF-α and IFN-γ by PBMCs after 72 h were significantly lower compared to 48 h stimulation by B. lactis (p<0.001, p<0.035 respectively). These data show that both probiotics may trigger the pro- and anti-inflammatory immune response of UC patients. It seems that IL-10/TGF-β uprising by B. lactis could be the reason of TNF-α/IFN-γ reduction. Therefore albeit B. lactis still stimulates the effector Th cells but because of more stimulatory effect on Tregs, it could be a good potential therapeutic candidate for further investigation. © Georg Thieme Verlag KG Stuttgart · New York.

Metagenomic Analysis of Dairy Bacteriophages: Extraction Method and Pilot Study on Whey Samples Derived from Using Undefined and Defined Mesophilic Starter Cultures.

PubMed

Muhammed, Musemma K; Kot, Witold; Neve, Horst; Mahony, Jennifer; Castro-Mejía, Josué L; Krych, Lukasz; Hansen, Lars H; Nielsen, Dennis S; Sørensen, Søren J; Heller, Knut J; van Sinderen, Douwe; Vogensen, Finn K

2017-10-01

Despite being potentially highly useful for characterizing the biodiversity of phages, metagenomic studies are currently not available for dairy bacteriophages, partly due to the lack of a standard procedure for phage extraction. We optimized an extraction method that allows the removal of the bulk protein from whey and milk samples with losses of less than 50% of spiked phages. The protocol was applied to extract phages from whey in order to test the notion that members of Lactococcus lactis 936 (now Sk1virus ), P335, c2 (now C2virus ) and Leuconostoc phage groups are the most frequently encountered in the dairy environment. The relative abundance and diversity of phages in eight and four whey mixtures from dairies using undefined mesophilic mixed-strain cultures containing Lactococcus lactis subsp. lactis biovar diacetylactis and Leuconostoc species (i.e., DL starter cultures) and defined cultures, respectively, were assessed. Results obtained from transmission electron microscopy and high-throughput sequence analyses revealed the dominance of Lc. lactis 936 phages (order Caudovirales , family Siphoviridae ) in dairies using undefined DL starter cultures and Lc. lactis c2 phages (order Caudovirales , family Siphoviridae ) in dairies using defined cultures. The 936 and Leuconostoc phages demonstrated limited diversity. Possible coinduction of temperate P335 prophages and satellite phages in one of the whey mixtures was also observed. IMPORTANCE The method optimized in this study could provide an important basis for understanding the dynamics of the phage community (abundance, development, diversity, evolution, etc.) in dairies with different sizes, locations, and production strategies. It may also enable the discovery of previously unknown phages, which is crucial for the development of rapid molecular biology-based methods for phage burden surveillance systems. The dominance of only a few phage groups in the dairy environment signifies the depth of knowledge

Metagenomic Analysis of Dairy Bacteriophages: Extraction Method and Pilot Study on Whey Samples Derived from Using Undefined and Defined Mesophilic Starter Cultures

PubMed Central

Muhammed, Musemma K.; Kot, Witold; Neve, Horst; Mahony, Jennifer; Castro-Mejía, Josué L.; Krych, Lukasz; Hansen, Lars H.; Nielsen, Dennis S.; Sørensen, Søren J.; Heller, Knut J.; van Sinderen, Douwe

2017-01-01

ABSTRACT Despite being potentially highly useful for characterizing the biodiversity of phages, metagenomic studies are currently not available for dairy bacteriophages, partly due to the lack of a standard procedure for phage extraction. We optimized an extraction method that allows the removal of the bulk protein from whey and milk samples with losses of less than 50% of spiked phages. The protocol was applied to extract phages from whey in order to test the notion that members of Lactococcus lactis 936 (now Sk1virus), P335, c2 (now C2virus) and Leuconostoc phage groups are the most frequently encountered in the dairy environment. The relative abundance and diversity of phages in eight and four whey mixtures from dairies using undefined mesophilic mixed-strain cultures containing Lactococcus lactis subsp. lactis biovar diacetylactis and Leuconostoc species (i.e., DL starter cultures) and defined cultures, respectively, were assessed. Results obtained from transmission electron microscopy and high-throughput sequence analyses revealed the dominance of Lc. lactis 936 phages (order Caudovirales, family Siphoviridae) in dairies using undefined DL starter cultures and Lc. lactis c2 phages (order Caudovirales, family Siphoviridae) in dairies using defined cultures. The 936 and Leuconostoc phages demonstrated limited diversity. Possible coinduction of temperate P335 prophages and satellite phages in one of the whey mixtures was also observed. IMPORTANCE The method optimized in this study could provide an important basis for understanding the dynamics of the phage community (abundance, development, diversity, evolution, etc.) in dairies with different sizes, locations, and production strategies. It may also enable the discovery of previously unknown phages, which is crucial for the development of rapid molecular biology-based methods for phage burden surveillance systems. The dominance of only a few phage groups in the dairy environment signifies the depth of knowledge

Yogurt-like beverages made of a mixture of cereals, soy and grape must: microbiology, texture, nutritional and sensory properties.

PubMed

Coda, Rossana; Lanera, Alessia; Trani, Antonio; Gobbetti, Marco; Di Cagno, Raffaella

2012-04-16

Cereal (rice, barley, emmer and oat) and soy flours and concentrated red grape must were used for making vegetable yogurt-like beverages (VYLB). Two selected strains of Lactobacillus plantarum were used for lactic acid fermentation, according to a process which included the flour gelatinization. All VLYB had values of pH lower than 4.0 and both selected starters remained viable at ca. 8.4 log cfu/g throughout storage. All VLYB showed high values of apparent viscosity and water holding capacity. During fermentation, lactic acid bacteria consumed glucose, fructose, and malic acid, which was supplied with grape must. Compared to control vegetable yogurt-like beverages (CVYLB), without bacterial inoculum, an increase of total free amino acids (FAA) was found during fermentation and storage. Also the concentration of polyphenolic compounds and ascorbic acid (ASC) was higher in VLYB compared to CVYLB. This was reflected on the antioxidant activity. As determined by Solid Phase Micro-Extraction/Gas-Chromatography/Mass-Spectrometry analysis, several volatile compounds were identified. Beverages made with the mixture of rice and barley or emmer flours seemed to possess the best combination textural, nutritional and sensory properties. Copyright © 2012 Elsevier B.V. All rights reserved.

Influence of starters on chemical, biochemical, and sensory changes in Turkish White-brined cheese during ripening.

PubMed

Hayaloglu, A A; Guven, M; Fox, P F; McSweeney, P L H

2005-10-01

Turkish White-brined cheese was manufactured using Lactococcus strains (Lactococcus lactis ssp. lactis NCDO763 plus L. lactis ssp. cremoris SK11 and L. lactis ssp. lactis UC317 plus L. lactis ssp. cremoris HP) or without a starter culture, and ripened for 90 d. It was found that the use of starters significantly influenced the physical, chemical, biochemical, and sensory properties of the cheeses. Chemical composition, pH, and sensory properties of cheeses made with starter were not affected by the different starter bacteria. The levels of soluble nitrogen fractions and urea-PAGE of the pH 4.6-insoluble fractions were found to be significantly different at various stages of ripening. Urea-PAGE patterns of the pH 4.6-insoluble fractions of the cheeses showed that considerable degradation of alpha(s1)-casein occurred and that beta-casein was more resistant to hydrolysis. The use of a starter culture significantly influenced the levels of 12% trichloroacetic acid-soluble nitrogen, 5% phosphotungstic acid-soluble nitrogen, free amino acids, total free fatty acids, and the peptide profiles (reverse phase-HPLC) of 70% (vol/vol) ethanol-soluble and insoluble fractions of the pH 4.6-soluble fraction of the cheeses. The levels of peptides in the cheeses increased during the ripening period. Principal component and hierarchical cluster analyses of electrophoretic and chromatographic results indicated that the cheeses were significantly different in terms of their peptide profiles and they were grouped based on the use and type of starter and stage of ripening. Levels of free amino acid in the cheeses differed; Leu, Glu, Phe, Lys, and Val were the most abundant amino acids. Nitrogen fractions, total free amino acids, total free fatty acids, and the levels of peptides resolved by reverse phase-HPLC increased during ripening. No significant differences were found between the sensory properties of cheeses made using a starter, but the cheese made without starter received lower

History of yogurt and current patterns of consumption.

PubMed

Fisberg, Mauro; Machado, Rachel

2015-08-01

Yogurt has been a part of the human diet for several millennia and goes by many names throughout the world. The word "yogurt" is believed to have come from the Turkish word "yoğurmak," which means to thicken, coagulate, or curdle. While references to the health-promoting properties of yogurt date back to 6000 BC in Indian Ayurvedic scripts, it was not until the 20th century that Stamen Grigorov, a Bulgarian medical student, attributed the benefits to lactic acid bacteria. Today, most yogurt is fermented milk that is acidified with viable and well-defined bacteria (Lactobacillus bulgaricus and Streptococcus thermophiles). While patterns of yogurt consumption vary greatly from country to country, consumption is generally low. In the United States and Brazil, for example, only 6% of the population consume yogurt on a daily basis. Low consumption of yogurt represents a missed opportunity to contribute to a healthy lifestyle, as yogurt provides a good to excellent source of highly bioavailable protein and an excellent source of calcium as well as a source of probiotics that may provide a range of health benefits. © The Author(s) 2015. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Consumer attitudes, knowledge, and consumption of organic yogurt.

PubMed

Van Loo, Ellen J; Diem, My Nguyen Hoang; Pieniak, Zuzanna; Verbeke, Wim

2013-04-01

The segment of organic products occupies an increasingly important place in dairy assortments. The European Union (EU) introduced a new EU organic logo in 2010 with the aim of harmonizing its organic sector and boosting consumer trust in organic food. This study focuses on organic yogurt and investigates consumer awareness and knowledge of the new EU logo. Consumers evaluate organic yogurt as superior compared with conventional yogurt on healthiness, environmental friendliness, quality, and safety. More frequent buyers of organic yogurt have a stronger belief that organic yogurt is superior. The willingness-to-pay for organic yogurt ranged from a premium of 15% for nonbuyers to 40% for habitual buyers, indicating the market potential for this product. A structural equations model reveals the positive association between knowledge, attitudes, and the frequency of purchasing and consuming organic yogurt. Nevertheless, consumer awareness of the EU organic logo remains rather low, which suggests a need for more effective information campaigns and marketing actions. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Detection of selected trace elements in yogurt components.

PubMed

Capcarova, Marcela; Harangozo, Lubos; Toth, Tomas; Schwarczova, Loretta; Bobkova, Alica; Stawarz, Robert; Guidi, Alessandra; Massanyi, Peter

2017-12-02

The objective of this study was to determine the concentrations of Cu, Cd, Pb, Mn, Cr, Co, Ni, Zn, and Hg in the white and fruit parts of commercially available yogurts (n = 30) from Nitra markets (Slovak Republic). The results were correlated to determine their relationships. Three yogurt fruit flavors were chosen and tested, strawberry (n = 10), blueberry (n = 10), and cherry (n = 10). The elements were analyzed using atomic absorption spectrophotometry. Higher concentrations of toxic elements, such as Cd and Pb, were found in the fruit parts of the yogurt, and in some cases, the tolerable limit was exceeded. The white part of the yogurt was not contaminated by toxic elements. White yogurt is a good source of nutrients for humans, but the fruit part in yogurt requires detailed monitoring and improvements in the processing techniques.

Selection of functional lactic acid bacteria as starter cultures for the fermentation of Korean leek (Allium tuberosum Rottler ex Sprengel.).

PubMed

Yang, Jaesik; Ji, Yosep; Park, Hyunjoon; Lee, Jieun; Park, Soyoung; Yeo, Soyoung; Shin, Hyunkil; Holzapfel, Wilhelm H

2014-11-17

The purpose of this research was to find safe and suitable starter cultures for the fermentation of Korean leek (Allium tuberosum Rottler), also known as garlic chives or Oriental garlic. This traditional herb has several functional properties and a strong flavour; its leaves are used as food material. Eighteen strains of lactic acid bacteria (LAB) were isolated from well-fermented leek kimchi. Controlled fermentation of the leek leaves was conducted with 2 strains (Weissella confusa LK4 and Lactobacillus plantarum LK8), selected as potential starter cultures on the basis of their safety properties, and on the pH, total titratable acidity (TTA), and viable cell numbers [colony forming units (CFUml(-1))] achieved during the fermentation. Microbial dynamics was also followed during fermentation by using PCR-DGGE (Denaturing Gradient Gel Electrophoresis) on DNA level. To analyse bioactive compounds such as thiols and allicin (diallyl thiosulfinates), the total flavonoid and polyphenolic contents were determined by colorimetric methods. Functional properties were assessed on the basis of anti-oxidative capacities by determining the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect, and ferric reducing antioxidant power (FRAP). W. confusa LK4 rapidly increased during the first stage of leek fermentation, and was mainly responsible for accelerated fermentation during the early period in contrast to L. plantarum LK8, a stronger acid producer during the later stages of fermentation. After 48 h fermentation, leeks fermented with W. confusa LK4 showed the highest radical scavenging effects and reducing ability. The detectable amount of allicin of fermented leeks decreased relative to the change in pH, whereas the concentration of thiols significantly increased. Total flavonoid and poly-phenolic contents changed during fermentation and showed correlation with anti-oxidant effects. We therefore suggest the suitability of W. confusa LK4 as a potential starter

Brettanomyces as a starter culture in rice-steamed sponge cake: a traditional fermented food in China.

PubMed

Wu, Peng; Xu, Xiaoyun; Xu, Yongxia; Chen, Qingchan; Pan, Siyi

2011-11-01

The potential use of Brettanomyces anomalus PSY-001 as an additional starter culture for the production of Rice-steamed sponge cake (RSSC), a traditional fermented food in China, was investigated. Two productions of RSSC, each containing batches of experimental cakes with Brettanomyces added and reference cakes with the leavened liquid added were carried out. For both experimental and reference cakes, chemical analysis and sensory evaluation were carried out during the fermentation period. The results showed that experimental cakes had desirable aroma and taste. The observed differences indicate a positive contribution to the overall quality of RSSC by B. anomalus PSY-001.

Invited review: Microbial evolution in raw-milk, long-ripened cheeses produced using undefined natural whey starters.

PubMed

Gatti, Monica; Bottari, Benedetta; Lazzi, Camilla; Neviani, Erasmo; Mucchetti, Germano

2014-02-01

The robustness of the starter culture during cheese fermentation is enhanced by the presence of a rich consortium of microbes. Natural starters are consortia of microbes undoubtedly richer than selected starters. Among natural starters, natural whey starters (NWS) are the most common cultures currently used to produce different varieties of cheeses. Undefined NWS are typically used for Italian cooked, long-ripened, extra-hard, raw milk cheeses, such as Parmigiano Reggiano and Grana Padano. Together with raw milk microbiota, NWS are responsible for most cheese characteristics. The microbial ecology of these 2 cheese varieties is based on a complex interaction among starter lactic acid bacteria (SLAB) and nonstarter lactic acid bacteria (NSLAB), which are characterized by their different abilities to grow in a changing substrate. This review aims to summarize the latest findings on Parmigiano Reggiano and Grana Padano to better understand the dynamics of SLAB, which mainly arise from NWS, and NSLAB, which mainly arise from raw milk, and their possible role in determining the characteristics of these cheeses. The review is presented in 4 main sections. The first summarizes the main microbiological and chemical properties of the ripened cheese as determined by cheese-making process variables, as these variables may affect microbial growth. The second describes the microbiota of raw milk as affected by specific milk treatments, from milking to the filling of the cheese milk vat. The third describes the microbiota of NWS, and the fourth reviews the knowledge available on microbial dynamics from curd to ripened cheese. As the dynamics and functionality of complex undefined NWS is one of the most important areas of focus in current food microbiology research, this review may serve as a good starting point for implementing future studies on microbial diversity and functionality of undefined cheese starter cultures. Copyright © 2014 American Dairy Science Association

Effect of starters and ripening time on the physicochemical, nitrogen fraction and texture profile of goat's cheese coagulated with a vegetable coagulant (Cynara cardunculus).

PubMed

García, Víctor; Rovira, Silvia; Boutoial, Khalid; Ferrandini, Eduardo; López Morales, María B

2014-02-01

The increase in the demand for goat's cheese throughout the world has encouraged research into the development of new related products with different textural characteristics. The aim of this work was to study the effect of three commercial starter cultures through the assessment of physicochemical and textural characteristics of goat's milk cheeses made with vegetable coagulant (Cynara cardunculus) during ripening. Use of the different starter cultures produced a significant effect (P < 0.05) on moisture, proteins, pH, nitrogen fractions and hardness of the cheeses. Results show that the addition of mesophilic starters ensures the correct acidification rate and produced cheeses with lower pH values and greater hardness. Use of thermophilic starter cultures produces cheeses with less instrumental hardness and the use of mixed cultures produced less proteolysis. These results are found useful for selecting the most suitable starter for the development of new goat's cheeses. © 2013 Society of Chemical Industry.

Frozen yogurt and ice cream were less healthy than yogurt, and adding toppings reduced their nutrition value: evidence from 1999-2014 National Health and Nutrition Examination Survey.

PubMed

An, Ruopeng; Jiang, Ning

2017-06-01

It was hypothesized that frozen yogurt and ice cream would be less healthy than yogurt. We examined daily energy and nutrient intake from yogurt, frozen yogurt, and ice cream among US adults. In-person 24-hour dietary recall data (n=6453) came from the 1999-2014 National Health and Nutrition Examination Survey. Regression analyses were performed to examine the differences in energy/nutrient intake from frozen yogurt and ice cream (with/without toppings) in comparison to yogurt. Approximately 5.3%, 0.9%, and 14.3% of US adults consumed yogurt, frozen yogurt, and ice cream on any given day, respectively. Among frozen yogurt and ice cream consumers, 29.7% and 14.8% added toppings to their consumption, respectively. Compared with yogurt, frozen yogurt consumption with and without toppings was associated with increased daily energy intake by 214.6 and 97.9kj, respectively; whereas ice cream consumption with and without toppings was associated with increased daily energy intake by 427.2 and 343.5kj, respectively. Compared with yogurt, frozen yogurt consumption was associated with a decreased intake of most vitamins/minerals under examination, but increased intake of sugar, total/saturated fat, cholesterol, fiber, and iron. Adding toppings to frozen yogurt further increased total and saturated fat intake. Compared with yogurt, ice cream consumption was associated with a decreased intake of multiple micronutrients, but increased intake of sugar, total/saturated fat, cholesterol, fiber, vitamins A and E, and iron. Adding toppings to ice cream further increased sugar intake. In conclusion, frozen yogurt and ice cream were less healthy than yogurt, and adding toppings made them even less desirable. Copyright © 2017 Elsevier Inc. All rights reserved.

Involvement of Acetobacter orientalis in the production of lactobionic acid in Caucasian yogurt ("Caspian Sea yogurt") in Japan.

PubMed

Kiryu, T; Kiso, T; Nakano, H; Ooe, K; Kimura, T; Murakami, H

2009-01-01

Lactobionic acid was first found in a Caucasian fermented milk product popularly known as "Caspian Sea yogurt" in Japan. The presence of lactobionic acid in the fermented milk was indicated by the results of both high-performance anion-exchange chromatographic analysis with pulsed amperometric detection and mass spectrometric analysis. Thereafter, the acid was purified from the yogurt and analyzed by nuclear magnetic resonance. A substantial amount of lactobionic acid was found to be accumulated in the upper layer of the yogurt, especially within 10 mm from the surface. A total of 45 mg of lactobionic acid per 100 g of the upper yogurt layer was collected after 4 d of fermentation. The annual intake of lactobionic acid in individuals consuming 100 g of the yogurt every day would be 0.5 to 1.0 g. A lactose-oxidizing bacterium was isolated from the fermented milk and was identified as Acetobacter orientalis. Washed A. orientalis cells oxidized monosaccharides such as d-glucose at considerable rates, although their activities for substrates such as lactose, maltose, and cellobiose were much lower. When A. orientalis cells were cultivated in cow's milk, they exhibited lactose-oxidizing activity, suggesting that this bacterium was the main organism involved in the production of lactobionic acid in the yogurt.

Development of a multiplex real time PCR to detect thermophilic lactic acid bacteria in natural whey starters.

PubMed

Bottari, Benedetta; Agrimonti, Caterina; Gatti, Monica; Neviani, Erasmo; Marmiroli, Nelson

2013-01-01

A multiplex real time PCR (mRealT-PCR) useful to rapidly screen microbial composition of thermophilic starter cultures for hard cooked cheeses and to compare samples with potentially different technological properties was developed. Novel primers directed toward pheS gene were designed and optimized for multiple detection of Lactobacillus helveticus, Lactobacillus delbrueckii, Streptococcus thermophilus and Lactobacillus fermentum. The assay was based on SYBR Green chemistry followed by melting curves analysis. The method was then evaluated for applications in the specific detection of the 4 lactic acid bacteria (LAB) in 29 different natural whey starters for Parmigiano Reggiano cheese production. The results obtained by mRealT-PCR were also compared with those obtained on the same samples by Fluorescence in Situ Hybridization (FISH) and Length-Heterogeneity PCR (LH-PCR). The mRealT-PCR developed in this study, was found to be effective for analyzing species present in the samples with an average sensitivity down to less than 600 copies of DNA and therefore sensitive enough to detect even minor LAB community members of thermophilic starter cultures. The assay was able to describe the microbial population of all the different natural whey starter samples analyzed, despite their natural variability. A higher number of whey starter samples with S. thermophilus and L. fermentum present in their microbial community were revealed, suggesting that these species could be more frequent in Parmigiano Reggiano natural whey starter samples than previously shown. The method was more effective than LH-PCR and FISH and, considering that these two techniques have to be used in combination to detect the less abundant species, the mRealT-PCR was also faster. Providing a single step sensitive detection of L. helveticus, L. delbrueckii, S. thermophilus and L. fermentum, the developed mRealT-PCR could be used for screening thermophilic starter cultures and to follow the presence of

Biodiversity of Lactobacillus helveticus bacteriophages isolated from cheese whey starters.

PubMed

Zago, Miriam; Bonvini, Barbara; Rossetti, Lia; Meucci, Aurora; Giraffa, Giorgio; Carminati, Domenico

2015-05-01

Twenty-one Lactobacillus helveticus bacteriophages, 18 isolated from different cheese whey starters and three from CNRZ collection, were phenotypically and genetically characterised. A biodiversity between phages was evidenced both by host range and molecular (RAPD-PCR) typing. A more detailed characterisation of six phages showed similar structural protein profiles and a relevant genetic biodiversity, as shown by restriction enzyme analysis of total DNA. Latent period, burst time and burst size data evidenced that phages were active and virulent. Overall, data highlighted the biodiversity of Lb. helveticus phages isolated from cheese whey starters, which were confirmed to be one of the most common phage contamination source in dairy factories. More research is required to further unravel the ecological role of Lb. helveticus phages and to evaluate their impact on the dairy fermentation processes where whey starter cultures are used.

Selection of lactic acid bacteria from Brazilian kefir grains for potential use as starter or probiotic cultures.

PubMed

Zanirati, Débora Ferreira; Abatemarco, Mário; Sandes, Sávio Henrique de Cicco; Nicoli, Jacques Robert; Nunes, Álvaro Cantini; Neumann, Elisabeth

2015-04-01

Brazilian kefir is a homemade fermented beverage that is obtained by incubating milk or a brown sugar solution with kefir grains that contribute their different microbiological compositions. It is highly important to isolate and characterize microorganisms from Brazilian kefir grains to obtain starter cultures for the industrial production of a standardized commercial kefir. Thus, the present study aimed to isolate lactic acid bacteria from eight kefir grains that were propagated in milk or sugar solutions from five different locations in Brazil and to select Lactobacillus isolates based on desirable in vitro probiotic properties. One hundred eight isolates from both substrates were identified by amplified ribosomal DNA restriction analysis and/or 16S rRNA gene sequencing and were determined to belong to the following 11 species from the genera: Lactococcus, Leuconostoc, Lactobacillus (L.), and Oenococcus. Leuconostoc mesenteroides, Lactobacillus kefiri, and Lactobacillus kefiranofaciens were isolated only from milk grains, whereas Lactobacillus perolens, Lactobacillus parafarraginis, Lactobacillus diolivorans, and Oenococcus oeni were isolated exclusively from sugar water grains. When the microbial compositions of four kefir grains were evaluated with culture-independent analyses, L. kefiranofaciens was observed to predominant in milk grains, whereas Lactobacillus hilgardii was most abundant in sugar water kefir. Unfortunately, L. hilgardii was not isolated from any grain, although this bacteria was detected with a culture-independent methodology. Fifty-two isolated Lactobacilli were tested for gastric juice and bile salt tolerance, antagonism against pathogens, antimicrobial resistance, and surface hydrophobicity. Three Lactobacillus strains (L. kefiranofaciens 8U, L. diolivorans 1Z, and Lactobacillus casei 17U) could be classified as potential probiotics. In conclusion, several lactic acid bacteria that could be used in combination with yeasts as starter

Effect of yogurt and bifidus yogurt fortified with skim milk powder, condensed whey and lactose-hydrolysed condensed whey on serum cholesterol and triacylglycerol levels in rats.

PubMed

Beena, A; Prasad, V

1997-08-01

The possible hypocholesterolaemic properties of milk and fermented milk products have been investigated in groups of albino rats given a basal diet, basal diet plus cholesterol, and basal diet plus cholesterol together with whole milk or standard or bifidus yogurt. The yogurts were fortified with skim milk powder, condensed whey or lactose-hydrolysed condensed whey. After 30 d, triacylglycerols, total cholesterol, HDL-cholesterol and LDL-cholesterol were measured in serum. Whole milk and ordinary yogurt had no hypocholesterolaemic effect, but standard yogurt containing lactose-hydrolysed condensed whey and all bifidus yogurts lowered serum cholesterol. In general, yogurts changed HDL-cholesterol little, but tended to raise triacylglycerols. There was marked lowering of LDL-cholesterol in rats given either type of yogurt fortified with whey proteins. This study has demonstrated in a rat model that bifidus yogurts and yogurts fortified with whey proteins can reduce total and LDL-cholesterol, and suggests that if they have the same effect in human subjects they have potential value in cholesterol-lowering diets.

Comparative genome analysis of the candidate functional starter culture strains Lactobacillus fermentum 222 and Lactobacillus plantarum 80 for controlled cocoa bean fermentation processes.

PubMed

Illeghems, Koen; De Vuyst, Luc; Weckx, Stefan

2015-10-12

Lactobacillus fermentum 222 and Lactobacillus plantarum 80, isolates from a spontaneous Ghanaian cocoa bean fermentation process, proved to be interesting functional starter culture strains for cocoa bean fermentations. Lactobacillus fermentum 222 is a thermotolerant strain, able to dominate the fermentation process, thereby converting citrate and producing mannitol. Lactobacillus plantarum 80 is an acid-tolerant and facultative heterofermentative strain that is competitive during cocoa bean fermentation processes. In this study, whole-genome sequencing and comparative genome analysis was used to investigate the mechanisms of these strains to dominate the cocoa bean fermentation process. Through functional annotation and analysis of the high-coverage contigs obtained through 454 pyrosequencing, plantaricin production was predicted for L. plantarum 80. For L. fermentum 222, genes encoding a complete arginine deiminase pathway were attributed. Further, in-depth functional analysis revealed the capacities of these strains associated with carbohydrate and amino acid metabolism, such as the ability to use alternative external electron acceptors, the presence of an extended pyruvate metabolism, and the occurrence of several amino acid conversion pathways. A comparative genome sequence analysis using publicly available genome sequences of strains of the species L. plantarum and L. fermentum revealed unique features of both strains studied. Indeed, L. fermentum 222 possessed genes encoding additional citrate transporters and enzymes involved in amino acid conversions, whereas L. plantarum 80 is the only member of this species that harboured a gene cluster involved in uptake and consumption of fructose and/or sorbose. In-depth genome sequence analysis of the candidate functional starter culture strains L. fermentum 222 and L. plantarum 80 revealed their metabolic capacities, niche adaptations and functionalities that enable them to dominate the cocoa bean fermentation

Competition between yogurt probiotics and periodontal pathogens in vitro.

PubMed

Zhu, Yunwo; Xiao, Liying; Shen, Da; Hao, Yuqing

2010-09-01

To investigate the competition between probiotics in bio-yogurt and periodontal pathogens in vitro. The antimicrobial activity of bio-yogurt was studied by agar diffusion assays, using eight species of putative periodontal pathogens and a 'protective bacteria' as indicator strains. Four probiotic bacterial species (Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus, and Bifidobacterium) were isolated from yogurt and used to rate the competitive exclusion between probiotics and periodontal pathogens. Fresh yogurt inhibited all the periodontal pathogens included in this work, showing inhibition zones ranging from 9.3 (standard deviation 0.6) mm to 17.3 (standard deviation 1.7) mm, whereas heat-treated yogurt showed lower antimicrobial activity. In addition, neither fresh yogurt nor heat-treated yogurt inhibited the 'protective bacteria', Streptococcus sanguinis. The competition between yogurt probiotics and periodontal pathogens depended on the sequence of inoculation. When probiotics were inoculated first, Bifidobacterium inhibited Porphyromonas gingivalis, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas circumdentaria, and Prevotella nigrescens; L. acidophilus inhibited P. gingivalis, A. actinomycetemcomitans, P. circumdentaria, P. nigrescens, and Peptostreptococcus anaerobius; L. bulgaricus inhibited P. gingivalis, A. actinomycetemcomitans, and P. nigrescens; and S. thermophilus inhibited P. gingivalis, F. nucleatum, and P. nigrescens. However, their antimicrobial properties were reduced when both species (probiotics and periodontal pathogens) were inoculated simultaneously. When periodontal pathogens were inoculated first, Prevotella intermedia inhibited Bifidobacterium and S. thermophilus. The results demonstrated that bio-yogurt and the probiotics that it contains are capable of inhibiting specific periodontal pathogens but have no effect on the periodontal protective bacteria.

The Effects of an Olive Fruit Polyphenol-Enriched Yogurt on Body Composition, Blood Redox Status, Physiological and Metabolic Parameters and Yogurt Microflora.

PubMed

Georgakouli, Kalliopi; Mpesios, Anastasios; Kouretas, Demetrios; Petrotos, Konstantinos; Mitsagga, Chrysanthi; Giavasis, Ioannis; Jamurtas, Athanasios Z

2016-06-03

In the present study we investigated the effects of an olive polyphenol-enriched yogurt on yogurt microflora, as well as hematological, physiological and metabolic parameters, blood redox status and body composition. In a randomized double-blind, crossover design, 16 (6 men, 10 women) nonsmoking volunteers with non-declared pathology consumed either 400 g of olive fruit polyphenol-enriched yogurt with 50 mg of encapsulated olive polyphenols (experimental condition-EC) or 400 g of plain yogurt (control condition-CC) every day for two weeks. Physiological measurements and blood collection were performed before and after two weeks of each condition. The results showed that body weight, body mass index, hip circumference and systolic blood pressure decreased significantly (p < 0.05) following the two-week consumption of yogurt regardless of condition. A tendency towards significance for decreased levels of low density lipoprotein (LDL) cholesterol (p = 0.06) and thiobarbituric acid reactive substances (p < 0.05) following two weeks of polyphenol-enriched yogurt consumption was observed. The population of lactic acid bacteria (LAB) and production of lactate in yogurt were significantly enhanced after addition of olive polyphenols, contrary to the population of yeasts and molds. The results indicate that consumption of the polyphenol-enriched yogurt may help individuals with non-declared pathology reduce body weight, blood pressure, LDL cholesterol levels and lipid peroxidation, and promote growth of beneficial LAB.

The Effects of an Olive Fruit Polyphenol-Enriched Yogurt on Body Composition, Blood Redox Status, Physiological and Metabolic Parameters and Yogurt Microflora

PubMed Central

Georgakouli, Kalliopi; Mpesios, Anastasios; Kouretas, Demetrios; Petrotos, Konstantinos; Mitsagga, Chrysanthi; Giavasis, Ioannis; Jamurtas, Athanasios Z.

2016-01-01

In the present study we investigated the effects of an olive polyphenol-enriched yogurt on yogurt microflora, as well as hematological, physiological and metabolic parameters, blood redox status and body composition. In a randomized double-blind, crossover design, 16 (6 men, 10 women) nonsmoking volunteers with non-declared pathology consumed either 400 g of olive fruit polyphenol-enriched yogurt with 50 mg of encapsulated olive polyphenols (experimental condition—EC) or 400 g of plain yogurt (control condition—CC) every day for two weeks. Physiological measurements and blood collection were performed before and after two weeks of each condition. The results showed that body weight, body mass index, hip circumference and systolic blood pressure decreased significantly (p < 0.05) following the two-week consumption of yogurt regardless of condition. A tendency towards significance for decreased levels of low density lipoprotein (LDL) cholesterol (p = 0.06) and thiobarbituric acid reactive substances (p < 0.05) following two weeks of polyphenol-enriched yogurt consumption was observed. The population of lactic acid bacteria (LAB) and production of lactate in yogurt were significantly enhanced after addition of olive polyphenols, contrary to the population of yeasts and molds. The results indicate that consumption of the polyphenol-enriched yogurt may help individuals with non-declared pathology reduce body weight, blood pressure, LDL cholesterol levels and lipid peroxidation, and promote growth of beneficial LAB. PMID:27271664

Indigenous Starter Cultures to Improve Quality of Artisanal Dry Fermented Sausages from Chaco (Argentina).

PubMed

Palavecino Prpich, Noelia Z; Castro, Marcela P; Cayré, María E; Garro, Oscar A; Vignolo, Graciela M

2015-01-01

Lactic acid bacteria (LAB) and coagulase negative cocci (CNC) were isolated from artisanal dry sausages sampled from the northeastern region of Chaco, Argentina. In order to evaluate their performance in situ and considering technological features of the isolated strains, two mixed selected autochthonous starter cultures (SAS) were designed: (i) SAS-1 (Lactobacillus sakei 487 + Staphylococcus vitulinus C2) and (ii) SAS-2 (L. sakei 442 + S. xylosus C8). Cultures were introduced into dry sausage manufacturing process at a local small-scale facility. Microbiological and physicochemical parameters were monitored throughout fermentation and ripening periods, while sensory attributes of the final products were evaluated by a trained panel. Lactic acid bacteria revealed their ability to colonize and adapt properly to the meat matrix, inhibiting the growth of spontaneous microflora and enhancing safety and hygienic profile of the products. Both SAS showed a beneficial effect on lipid oxidation and texture of the final products. Staphylococcus vitulinus C2, from SAS-1, promoted a better redness of the final product. Sensory profile revealed that SAS addition preserved typical sensory attributes. Introduction of these cultures could provide an additional tool to standardize manufacturing processes aiming to enhance safety and quality while keeping typical sensory attributes of regional dry fermented sausages.

Effect of starter culture, spice mix and storage time and temperature on biogenic amine content of dry fermented sausages.

PubMed

Komprda, T; Smělá, D; Pechová, P; Kalhotka, L; Stencl, J; Klejdus, B

2004-08-01

Two types of dry fermented sausage differing in spicing mixture and the diameter (low content of red pepper+diameter 80 mm, H-sausage; high content of red pepper+diameter 55 mm, P-sausage, respectively) were produced in parallel with two different starter cultures (Pediococcus pentosaceus+Staphylococcus carnosus, B-samples and S. carnosus+Staphylococcus xylosus+Lactobacillus farciminis, F-samples, respectively). The sausages were ripened 21 days and subsequently stored 91 days at the room temperature. Concentration of both most abundant amines, putrescine and tyramine (y; mg/kg DM) increased significantly (P<0.01) in HB-sausage during ripening (x; days): y=2.5+18.13x-0.3144x(2) (R(2)=0.99) and y=0.7+8.17x-0.1130x(2) (R(2)=0.99), and also during storage: y=127.3+5.123x (R(2)=0.79) and y=26.0+3.211x (R(2)=0.74), respectively. At the end of ripening, putrescine (247 mg/kg DM) and tyramine (123 mg/kg DM) content in the HB-sausage was higher (P<0.05) than in the PB-sausage (12 and 9 mg/kg DM, respectively), concentration of either of these amines was negligible (1 mg/kg DM) in either type of F-inoculated sausage. Both starter culture and sausage type influenced significantly (P<0.001) both putrescine and tyramine content in the sausage; starter accounted for 57% and 55% of total variability in putrescine and tyramine content, respectively. Due to the significant (P<0.05) increase of total aerobic counts in the HB-sausage between the end of ripening and the 7th day of storage, followed by the significant (P<0.01) increase of the sum of total biogenic amines between the end of ripening (425 mg/kg DM) and the end of storage (1029 mg/kg DM), the storage of the dry fermented sausages at the room temperature should not be recommended.

Determination of antioxidant activity of bioactive peptide fractions obtained from yogurt.

PubMed

Aloğlu, H Sanlıdere; Oner, Z

2011-11-01

In this study, physicochemical and microbiological properties of traditional and commercial yogurt samples were determined during 4 wk of storage. Proteolytic activity, which occurs during the storage period of yogurt samples, was also determined. Peptide fractions obtained from yogurts were investigated and the effect of proteolysis on peptide release during storage was determined. The antioxidant activities of peptides released from yogurt water-soluble extracts (WSE) and from HPLC fractions were determined by 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods. The antioxidant activity of WSE from traditional yogurt was greater than that of WSE from commercial yogurts. In analysis by the ABTS method, mean values increased from 7.697 to 8.739 mM Trolox/g in commercial yogurts, and from 10.115 to 13.182 mM Trolox/g in traditional yogurts during storage. Antioxidant activities of peptides released from HPLC fractions of selected yogurt samples increased 10 to 200 times. In all yogurt samples, the greatest antioxidant activity was shown in the F2 fraction. After further fractionation of yogurt samples, the fractions coded as F2.2, F2.3, F4.3, and F4.4 had the highest antioxidant activity values. Total antioxidant activity of yogurts was low but after purification of peptides by fractionation in HPLC, peptide fractions with high antioxidant activity were obtained. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Use of lacticin 481 to facilitate delivery of the bacteriophage resistance plasmid, pCBG104 to cheese starters.

PubMed

Mills, S; Coffey, A; O'Sullivan, L; Stokes, D; Hill, C; Fitzgerald, G F; Ross, R P

2002-01-01

Use of lacticin 481 to facilitate the conjugal transfer of the bacteriophage resistance plasmid pCBG104 to various starter cultures. A raw milk isolate of Lactococcus was found to harbour determinants for lacticin 481 production and immunity and phage resistance on a plasmid designated pCBG104. The lacticin 481 was successfully used to mobilize the phage resistance determinant to a variety of cheese starters enabling the formation of highly phage resistant starters. In addition, it facilitated the stacking of a number of phage resistance genes, namely a type I restriction modification system, a phage abortive infection system and a phage adsorption blocking system in a single Lactococcus strain without the use of recombinant techniques. The transconjugants were all shown to produce lacticin 481 and to contain the entire 481 operon. Subsequently one transconjugant was selected and successfully used for large-scale cheddar cheese manufacture. Lacticin 481 could be used as a food-grade selectable marker to facilitate the introduction of advantageous traits to starter cultures for industrial food fermentations. Food-grade selectable markers greatly facilitate the introduction of various advantageous traits to starter cultures for industrial food fermentation. Indeed self-cloning which is becoming increasingly important for strain improvement has a requirement for the identification and demonstration of the utility of tools such as lacticin 481.

Effect of varying the salt and fat content in Cheddar cheese on aspects of the performance of a commercial starter culture preparation during ripening.

PubMed

Yanachkina, Palina; McCarthy, Catherine; Guinee, Tim; Wilkinson, Martin

2016-05-02

Production of healthier reduced-fat and reduced-salt cheeses requires careful selection of starter bacteria, as any substantial alterations to cheese composition may prompt changes in the overall performance of starters during cheese ripening. Therefore, it is important to assess the effect of compositional alterations on the individual strain response during cheese ripening for each optimised cheese matrix. In the current study, the effect of varying fat and salt levels in Cheddar cheese on the performance of a commercial Lactococcus lactis culture preparation, containing one L. lactis subsp. lactis strain and one L. lactis subsp. cremoris strain was investigated. Compositional variations in fat or salt levels did not affect overall starter viability, yet reduction of fat by 50% significantly delayed non-starter lactic acid bacteria (NSLAB) populations at the initial ripening period. In comparison to starter viability, starter autolysis, as measured by release of intracellular lactate dehydrogenase (LDH) or post-proline dipeptidyl aminopeptidase (Pep X) into cheese juices, decreased significantly with lower salt addition levels in full-fat Cheddar. Conversely, reducing fat content of cheese resulted in a significantly higher release of intracellular Pep X, and to a lesser extent intracellular LDH, into juices over ripening. Flow cytometry (FCM) indicated that the permeabilised and dead cell sub-populations were generally lower in juices from cheeses with reduced salt content, however no significant differences were observed between different salt and fat treatments. Interestingly, fat reductions by 30 and 50% in cheeses with reduced or half added salt contents appeared to balance out the effect of salt, and enhanced cell permeabilisation, cell death, and also cell autolysis in these variants. Overall, this study has highlighted that alterations in both salt and fat levels in cheese influence certain aspects of starter performance during ripening, including

The Comparison of vaginal cream of mixing yogurt, honey and clotrimazole on symptoms of vaginal candidiasis.

PubMed

Darvishi, Maryam; Jahdi, Fereshteh; Hamzegardeshi, Zeinab; Goodarzi, Saied; Vahedi, Mohsen

2015-04-03

Vulvovaginal candidiasis is known as one of the most common fungal infection among women of reproductive age and considered as an important public health problem. In recent years, due to resistance to common antifungal medication, the use of traditional medicine of anti-fungal and herbal treatment increased. Therefore the objective of this study was to determine the effects of vaginal cream, mixture of yogurt and honey and comparing it with clotrimazole vaginal cream on symptoms of Vulvovaginal candidiasis in patients. In this randomized, triple blind clinical trial of 70 non-pregnant women infected with Candidal vulvovaginitis were placed in two groups of Vaginal cream mixed of yogurt and honey recipients (N=35) and clotrimazole vaginal cream (N=35). Both groups were treated for 7 days. At the beginning of study, Clinical and laboratory signs and symptoms were registered 7 and 14 days after treatment by questionnaire, observation form and secretions culture results. Data by chi-square test, t test, McNemar tests were analyzed by SPSS version 21. Significance level of 0.05 was considered. The result of present study reveals the significant differences in symptom improvement of ' yogurt and honey, than clotrimazole group (P<0.05) and also Positive results of the first cultures (one week after treatment) in "yogurt and honey" and clotrimazole (20% versus 8.6%) and second time cultivation (14 days after treatment) (17/1% versus 8.6%) were similar and there was no significant differences between the two groups. (P>0.05) CONCLUSION: This study indicated that he therapeutic effects of vaginal cream, yogurt and honey is not only similar with clotrimazole vaginal cream but more effective in relieving some symptoms of vaginal candidiasis. Therefore, the use of this product can be suggested as an herbal remedy for candida infection treatment.

The Comparison of Vaginal Cream of Mixing Yogurt, Honey and Clotrimazole on Symptoms of Vaginal Candidiasis

PubMed Central

Darvishi, Maryam; Jahdi, Fereshteh; Hamzegardeshi, Zeinab; Goodarzi, Saied; Vahedi, Mohsen

2015-01-01

Background: Vulvovaginal candidiasis is known as one of the most common fungal infection among women of reproductive age and considered as an important public health problem. In recent years, due to resistance to common antifungal medication, the use of traditional medicine of anti-fungal and herbal treatmentis increased. Therefore the objective of this study was to determine the effects of vaginal cream, mixture of yogurt and honey and comparing it with clotrimazole vaginal cream on symptoms of Vulvovaginal candidiasis in patients. Methods: In this randomized, triple blind clinical trial of 70 non-pregnant women infected with Candidalvulvovaginitis were placed in two groups of Vaginal cream mixed of yogurt and honey recipients (N = 35) and clotrimazole vaginal cream (N = 35). Both groups were treated for 7 days.At the beginning of study, Clinical and laboratory signs and symptoms were registered 7 and 14 days after treatment by questionnaire, observation formand secretions medium culture results. Data were analyzed by chi-square test, t test, McNemar tests through SPSS version 21. Significance level of 0.05 was considered. Results: The result of present study reveals the significant differences in symptom improvement of yogurt and honey, toward clotrimazole group (P < 0.05) and also Positive results of the first cultures (one week after treatment) in “yogurt and honey” and clotrimazole (20% versus 8.6%) and second time cultivation (14 days after treatment) (17.1% versus 8.6%) were similar and there was no significant differences between the two groups. (P > 0.05). Conclusion: This study indicated that the therapeutic effects of vaginal cream, yogurt and honey is not only similar with clotrimazole vaginal cream but is more effective in relieving some symptoms of vaginal candidiasis. Therefore, the use of this product can be suggested as an herbal remedy for candida infection treatment. PMID:26153168

Association between yogurt consumption, dietary patterns, and cardio-metabolic risk factors.

PubMed

Cormier, Hubert; Thifault, Élisabeth; Garneau, Véronique; Tremblay, Angelo; Drapeau, Vicky; Pérusse, Louis; Vohl, Marie-Claude

2016-03-01

To examine whether yogurt consumption is associated with a healthier dietary pattern and with a better cardio-metabolic risk profile among healthy individuals classified on the basis of their body mass index (BMI). A 91-item food frequency questionnaire, including data on yogurt consumption, was administered to 664 subjects from the INFOGENE study. After principal component analysis, two factors were retained, thus classified as the Prudent and Western dietary patterns. Yogurt was a significant contributor to the Prudent dietary pattern. Moreover, yogurt consumption was associated with lower body weight, waist-to-hip ratio, and waist circumference and tended to be associated with a lower BMI. Consumers had lower levels of fasting total cholesterol and insulin. Consumers of yogurt had a positive Prudent dietary pattern mean score, while the opposite trend was observed in non-consumers of yogurt. Overweight/obese individuals who were consumers of yogurts exhibited a more favorable cardio-metabolic profile characterized by lower plasma triglyceride and insulin levels than non-consumers within the same range of BMI. There was no difference in total yogurt consumption between normal-weight individuals and overweight/obese individuals. However, normal-weight subjects had more daily servings of high-fat yogurt and less daily servings of fat-free yogurt compared to overweight/obese individuals. Being a significant contributor to the Prudent dietary pattern, yogurt consumption may be associated with healthy eating. Also, yogurt consumption may be associated with lower anthropometric indicators and a more beneficial cardio-metabolic risk profile in overweight/obese individuals.

Chemical, Physiochemical, and Microstructural Properties, and Probiotic Survivability of Fermented Goat Milk Using Polymerized Whey Protein and Starter Culture Kefir Mild 01.

PubMed

Wang, Hao; Wang, Cuina; Wang, Mu; Guo, Mingruo

2017-11-01

A set-type fermented goat milk (FGM) using polymerized whey protein (PWP) as main thickening agent and Kefir Mild 01 as starter culture was developed. The FGM with PWP (0.3%, w/v) and pectin (0.2%, w/v) had low syneresis (5.44 ± 0.92%), desirable viscosity (952.86 ± 61.52 mPa⋅s), and hardness (112.57 ± 3.23 g), which were comparable to a fermented cow milk. Sensory evaluation data showed that the FGM with PWP and pectin had higher scores of both flavor (4.41 ± 0.39) and taste (3.72 ± 0.34) than the sample without PWP. Chemical composition of both fermented goat and cow milk were analyzed. The protein content of goat and cow milk samples were 3.50% ± 0.12% and 3.28% ± 0.09% (w/w), respectively. Lactobacillus acidophilus population in both FGM samples remained above 10 6 CFU/g during the 1st 4-wk storage. There was a slight but no significant (P > 0.05) decrease in pH and TA during storage. Scanning electron microscopy micrographs displayed a compact and homogeneous protein network of the FGM with PWP and pectin. Polymerized whey protein may be a novel protein-based thickening agent for formulation of a set-type FGM with starter culture Kefir Mild 01. Fermented goat milk is an increasingly popular dairy product in the world. However, it is difficult to make set type fermented goat milk due to the smaller size and lower content of casein micelles in goat milk. A fermented goat milk with PWP (0.3%, w/v) and pectin (0.2%, w/v) was successfully developed in this study. The product fermented by Kefir Mild 01 starter culture had a similar taste with Kefir but no yeast or alcoholic exists. The new product would be a promising food in the market. © 2017 Institute of Food Technologists®.

Effect of fortification with various types of milk proteins on the rheological properties and permeability of nonfat set yogurt.

PubMed

Peng, Y; Serra, M; Horne, D S; Lucey, J A

2009-01-01

Yogurt base was prepared from reconstituted skim milk powder (SMP) with 2.5% protein and fortified with additional 1% protein (wt/wt) from 4 different milk protein sources: SMP, milk protein isolate (MPI), micellar casein (MC), and sodium caseinate (NaCN). Heat-treated yogurt mixes were fermented at 40 degrees C with a commercial yogurt culture until pH 4.6. During fermentation pH was monitored, and storage modulus (G') and loss tangent (LT) were measured using dynamic oscillatory rheology. Yield stress (sigma(yield)) and permeability of gels were analyzed at pH 4.6. Addition of NaCN significantly reduced buffering capacity of yogurt mix by apparently solubilizing part of the indigenous colloidal calcium phosphate (CCP) in reconstituted SMP. Use of different types of milk protein did not affect pH development except for MC, which had the slowest fermentation due to its very high buffering. NaCN-fortified yogurt had the highest G' and sigma(yield) values at pH 4.6, as well as maximum LT values. Partial removal of CCP by NaCN before fermentation may have increased rearrangements in yogurt gel. Soluble casein molecules in NaCN-fortified milks may have helped to increase G' and LT values of yogurt gels by increasing the number of cross-links between strands. Use of MC increased the CCP content but resulted in low G' and sigma(yield) at pH 4.6, high LT and high permeability. The G' value at pH 4.6 of yogurts increased in the order: SMP = MC < MPI < NaCN. Type of milk protein used to standardize the protein content had a significant impact on physical properties of yogurt. Practical Application: In yogurt processing, it is common to add additional milk solids to improve viscosity and textural attributes. There are many different types of milk protein powders that could potentially be used for fortification purposes. This study suggests that the type of milk protein used for fortification impacts yogurt properties and sodium caseinate gave the best textural results.

The evaluation of kefir pure culture starter: Liquid-core capsule entrapping microorganisms isolated from kefir grains.

PubMed

Wang, Liang; Zhong, Hao; Liu, Keying; Guo, Aizhen; Qi, Xianghui; Cai, Meihong

2016-10-01

The main purpose of this study was to develop a pure culture starter for producing kefir. In order to accomplish starter recycling, yeasts (Kluyveromyces marxianus strain, Pichia kudriavzevii clone), lactic acid bacteria (Lactobacillus kefiri strain F4Aa, Lactobacillus kefiri strain NM131-7, Lactobacillus kefiri strain NM132-3, Lactobacillus kefiri strain NM180-3, respectively), and acetic acid bacteria (Acetobacter lovaniensis strain) were entrapped in liquid core capsules based on the distribution ratio in kefir grains. The microbiological, antimicrobial, and chemical properties of kefir made with capsules (M) and kefir grains (K) were measured and compared. According to the results of plate counts in different selective medium, the number of yeasts and bacteria in the liquid core capsules gradually increased and stabilized after eight fermentation cycles. The results of gas chromatography-mass spectrometry showed that almost all the aroma components existed in the two type of kefir, except the ethyl lactate. There was no significant difference in alcohol content, protein content, and fat content, except the acidity and sugar content. Water holding capacity of kefir K was higher than kefir M. There were 14 same free amino acids in kefir M and kefir K, and the content of most free amino acids was similar. In antimicrobial test, there was no significant difference in both kefirs. © The Author(s) 2016.

Penicillium salamii strain ITEM 15302: A new promising fungal starter for salami production.

PubMed

Magistà, D; Ferrara, M; Del Nobile, M A; Gammariello, D; Conte, A; Perrone, G

2016-08-16

Traditional sausages are often considered of superior quality to sausages inoculated with commercial starter cultures and this is partially due to the action of the typical house microflora. Penicillium nalgiovense is the species commonly used as starter culture for dry-cured meat production. Recently a new species, Penicillium salamii, was described as typical colonizer during salami seasoning. In order to understand its contribution to the seasoning process, two different experiments on curing of fresh pork sausages were conducted using P. salamii ITEM 15302 in comparison with P. nalgiovense ITEM 15292 at small and industrial scale, and the dry-cured sausages were subjected to sensory analyses. Additionally, proteolytic and lipolytic in vitro assays were performed on both strains. P. salamii ITEM 15302 proved to be a fast growing mould on dry-cured sausage casings, well adapted to the seasoning process, with high lipolytic and proteolytic enzymatic activity that confers typical sensory characteristics to meat products. Therefore, P. salamii ITEM 15302 was shown to be a good candidate as new starter for meat industry. Copyright © 2015 Elsevier B.V. All rights reserved.

Enhancement of γ-aminobutyric acid (GABA) in Nham (Thai fermented pork sausage) using starter cultures of Lactobacillus namurensis NH2 and Pediococcus pentosaceus HN8.

PubMed

Ratanaburee, Anussara; Kantachote, Duangporn; Charernjiratrakul, Wilawan; Sukhoom, Ampaitip

2013-10-15

The aim was to produce Nham that was enriched with γ-aminobutyric acid (GABA); therefore two GABA producing lactic acid bacteria (Pediococcus pentosaceus HN8 and Lactobacillus namurensis NH2) were used as starter cultures. By using the central composite design (CCD) we showed that addition of 0.5% monosodium glutamate (MSG) together with an inoculum size of roughly 6logCFU/g of each of the two strains produced a maximal amounts of GABA (4051 mg/kg) in the 'GABA Nham' product. This was higher than any current popular commercial Nham product by roughly 8 times. 'GABA Nham' with the additions of both starters and MSG (TSM) supported maximum populations of lactic acid bacteria (LAB) with a minimum of yeasts and no staphylococci or molds when compared to the controls that had no addition of any starters or MSG (TNN), or only the addition of MSG (TNM), or with only the starter (TSN). Based on proximate analysis among the Nham sets, 'GABA Nham' was low in fat, carbohydrate and energy although its texture and color were slightly different from the control (TNN). However, sensory evaluations of 'GABA Nham' were more acceptable than the controls and commercial Nham products for all tested parameters. Hence, a unique novel 'GABA Nham' fermented pork sausage was successfully developed. © 2013.

Use of just-about-right scales and penalty analysis to determine appropriate concentrations of stevia sweeteners for vanilla yogurt.

PubMed

Narayanan, P; Chinnasamy, B; Jin, L; Clark, S

2014-01-01

With the mainstream emergence of natural sweeteners such as stevia, which is available in different commercial formulations, suitability for yogurt needs to be validated. The present study aimed to determine the appropriate concentration level of 3 processed stevia sweeteners/supplements in commercial plain low-fat yogurt flavored with natural vanilla. Three different levels of sucrose, aspartame, an erythritol and 95% rebaudiana A stevia sweetener, a 95% pure mix of maltodextrin and steviol glycosides, and a cold water stevia extract were used in the study. The just-about-right level for each sweetener and consumer acceptability of each naturally flavored low-fat vanilla yogurt were evaluated. Results from penalty analysis demonstrated that only 0.7% of stevia containing maltodextrin and 95% steviol glycoside was necessary, whereas higher levels (between 4.0 to 5.5%) were more appropriate for stevia containing erythritol and 95% rebaudiana A or cold water extract of stevia, respectively. The concentrations of stevia sweeteners used influenced the perceived sweetness and sourness. In general, consumers disliked the yogurt sweetened with stevia or aspartame, and neither disliked nor liked the yogurt sweetened with sucrose, which was largely driven by perceived sourness of the base yogurt. The findings underline the importance of careful selection of stevia type and concentration as well as optimizing yogurt cultures and fermentation conditions before product launch. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Polycyclic aromatic hydrocarbons (PAHs) in yogurt samples.

PubMed

Battisti, Chiara; Girelli, Anna Maria; Tarola, Anna Maria

2015-01-01

The concentrations and distributions of major polycyclic aromatic hydrocarbons (PAHs) were determined in 20 kinds of yogurt specimens collected from Italian supermarkets using reversed phase high-performance liquid chromatography equipped with fluorescence detection. The method was validated by determination of recovery percentages, precision (repeatability) and sensitivity (limits of detection) with yogurt samples fortified at 0.25, 0.5 and 1 µg/kg concentration levels. The recovery of 13 PAHs, with the exception of naphthalene and acenaphthene, ranged from 61% to 130% and from 60% to 97% at all the levels for yogurts with low (0.1%) and high (3.9%) fat content, respectively. The method is repeatable with relative standard deviation values <20% for all analytes. The results obtained demonstrate that acenaphthene, fluorantene, phenanthrene, anthracene, fluoranthene and pyrene were found in all samples with a similar distribution, but different content when yogurts with low and high fats were compared.

[Yogurt consumption and reduced risk of overweight and obesity in adults].

PubMed

Martinchik, A N; Baturin, A K; Peskova, E V; Keshabyants, E E; Mikhaylov, N A

2016-01-01

Fermented dairy products comprise a large food group in Russia and are an important source of dietary nutrients like protein, calcium, fat. Obesity is a rising public health issue in Russia. Observing the role of fermented dairy in the maintenance of healthy weights is important. Current study objective was to explore the association between obesity/overweight prevalence and yogurt consumption in Russian adults. Data from RLMS-HSE 1994-2012 was used. Primary materials are available on http://www.cpc.unc.edu/projects/rlms-hse, http://www. hse.ru/org/hse/rlms. Data collected included dietary intake by single 24h recalls and anthropometric measures for 72.400 adults (≥ 19 y.o.). Logistic regression models were used to explore the relationships between yogurt consumption and obesity prevalence (BMI > 30.0 compared with. 18.5-25.0), controlling for age and gender. Daily average intake (g/day) of yogurt significantly increased from 1994 to 2012. Yogurt consumption decreased over 40 y.o. in both gender. Women yogurt consumption is inversely correlated with the magnitude of the BMI: the consumption of yogurt in women with normal BMI values (> 18.5-25.0) was significantly higher than in women who are overweight and/or obese (BMI > 25.0; or > 30.0). The mean values of BMI in women who ate yogurt, were significantly lower than in women not consuming yogurt. In men, the relationship between consumption of yogurt and BMI is not revealed. Thus, among women, a significant inverse association was observed between yogurt consumption and obesity (OR 0.582, CI 95% 0.497, 0.680; p < 0.001). The observed association between yogurt intake and prevalence of obesity is dependent on gender: yogurt is associated with lower obesity prevalence only in women.

Improvement of carotenoid-synthesizing yeast Rhodotorula rubra by chemical mutagenesis.

PubMed

Frengova, Ginka I; Simova, Emilina D; Beshkova, Dora M

2004-01-01

A mutant Rhodotorula rubra with enhanced carotenoid-synthesizing activity for synthesizing total carotenoids and beta-carotene was obtained by N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. When co-cultivated with yogurt starter bacteria (Lactobacillus bulgaricus + Streptococcus thermophilus) in whey ultrafiltrate it produced 15.7 mg total carotenoids l(-1) culture fluid or 946 microg total carotenoids g(-1) dry cells of which 71% was beta-carotene. Grown as a monoculture in glucose substrate, the mutant shown 1.4 times lower carotenoid-synthesizing activity, and the relative share of beta-carotene in the total carotenoids was lower (63%). The individual pigments torulene and torularhodin were identified, whose mass fractions were (29% and 7%) and (24% and 4%), respectively, for the mutant grown as a monoculture and as a mixed culture with the yogurt bacteria.

7 CFR 58.406 - Starter facility.

Code of Federal Regulations, 2010 CFR

2010-01-01

... precaution shall be taken to prevent contamination of the facility, equipment and the air therein. A filtered air supply with a minimum average efficiency of 90 percent when tested in accordance with the ASHRAE....406 Starter facility. A separate starter room or properly designed starter tanks and satisfactory air...

Biocompatible yogurt carbon dots: evaluation of utilization for medical applications

NASA Astrophysics Data System (ADS)

Dinç, Saliha; Kara, Meryem; Demirel Kars, Meltem; Aykül, Fatmanur; Çiçekci, Hacer; Akkuş, Mehmet

2017-09-01

In this study, carbon dots (CDs) were produced from yogurt, a fermented milk product, via microwave-assisted process (800 W) in 30 min without using any additional chemical agents. Yogurt CDs had outstanding nitrogen and oxygen ratios. These dots were monodisperse and about 2 nm sized. The toxicological assessments of yogurt carbon dots in human cancer cells and normal epithelial cells and their fluorescence imaging in living cell system were carried out. Yogurt carbon dots had intense fluorescent signal under confocal microscopy and good fluorescence stability in living cell system. The resulting yogurt carbon dots exhibited high biocompatibility up to 7.1 mg/mL CD concentration which may find utilization in medical applications such as cellular tracking, imaging and drug delivery. Yogurt carbon dots have potential to be good diagnostic agents to visualize cancer cells which may be developed as a therapeutic carrier.

Postprandial plasma D-lactate concentrations after yogurt ingestion.

PubMed

de Vrese, M; Barth, C A

1991-06-01

The risk of D-lactic acidosis after consumption of yogurt was investigated in seven healthy volunteers. After ingestion of yogurt containing 1.06 mmol/kg body weight, D-lactic acid postprandial plasma D-lactate concentrations increased from 0.070 +/- 0.020 to a maximum of 0.200 +/- 0.010 mmol/l within 60 min. That was half the maximum concentration after the equivalent amount of D-lactate in the form of an aqueous solution of DL-lactate. The shape of the postprandial plasma D-lactate peak was flatter, but much broader after yogurt than after the aqueous solution, the peak areas being equal. When 0.64 mmol/kg body weight D-lactate were consumed as yogurt, plasma concentrations amounted to 0.086 +/- 0.030 mmol/l. Signs of a mild, transient, compensated metabolic acidosis, which was apparent in case of the aqueous lactic acid solution did not occur in case of yogurt. It is concluded that the consumption of foods containing D-lactic acid gives no reason for concern in healthy adults.

Biogenic amine content in dry fermented sausages as influenced by a producer, spice mix, starter culture, sausage diameter and time of ripening.

PubMed

Komprda, T; Sládková, P; Dohnal, V

2009-11-01

Sixteen types of dry fermented sausages were commercially produced as combinations of two producers (designated K and R), two starter cultures (Pediococcus pentosaceus, C; Lactobacillus curvatus+Staphylococcus carnosus, F), two spicing mixtures (H; P) and two casing diameters (4.5cm, T; 7cm, W), and were sampled at days zero, 14, 28 (end of ripening), 49, 70, 91 and 112 (samples were stored at 15°C and relative humidity of 70% between days 28 and 112). Tyramine and putrescine content (Y, mgkg(-1)) increased (P<0.01) with increasing time of ripening/storage (X, days): Y=52.0+5.19X-0.0275X(2) (R(2)=0.60) and Y=37.0+3.45X-0.0192X(2) (R(2)=0.23), respectively. Smaller diameter (T), spice mix containing red pepper (P) and starter culture C decreased (P<0.05) both tyramine and putrescine content in the sausages as compared to the W, H and F counterparts, respectively; content of both amines was lower (P<0.05) in the K-sausages than in the R-sausages. Tyramine content in the sausages at the time interval 28days of ripening+21days of storage was in the range from 170 (KHCU sausage combination) to 382 (RHFS) mgkg(-1).

Yogurt Consumption as a Signature of a Healthy Diet and Lifestyle.

PubMed

Tremblay, Angelo; Panahi, Shirin

2017-07-01

Yogurt is considered to be a nutrient-dense food that significantly contributes to the intake of several nutrients, including calcium and protein. As described in this paper, yogurt consumers have a higher nutrient intake than do nonconsumers. Yogurt consumers are also characterized by healthier dietary habits than nonconsumers, which partly explains their reduced incidence of overweight and obesity. Recent studies also suggest that yogurt consumers exhibit healthier nonnutritional behaviors, such as reduced smoking and greater participation in physical activity, than do nonconsumers. Furthermore, when greenhouse gas emissions are used as an additional criterion to categorize foods, yogurt appears to be an eco-friendly food. Compared with that of other foods, the carbon footprint of yogurt production is low to moderate and may be included as part of a healthy and sustainable diet. Based on these factors, yogurt consumption may be the signature of a healthy diet and lifestyle. © 2017 American Society for Nutrition.

[The microflora of sour dough. IV. Communication: bacterial composition of sourdough starters genus Lactobacillus beijerinck (author's transl)].

PubMed

Spicher, G; Schröder, R

1978-11-28

The bacterial composition of three so called pure culture sourdough starters of varying origin was investigated. 245 isolates were obtained all belonging to the genus Beijerinck. According to their morphological, physiological and biochemical characteristics they were classified into the subgroups: Thermobacterium (L. acidophilus), Streptobacterium (L. casei, L. plantarum, L. farciminis, L. alimentarius) and Betabacterium (L. brevis, L. brevis var. lindneri, L buchneri, L. fermentum, L. fructi vorans). In the three sourdough starters the identified lactic organisms varied in number and proportion. In starter preparation "A" only the varieties L. fructi vorans and L. fermentum were present. Preparation "B" contained a great variety of microorganisms with L. brevis and L. brevis L. lindneri predominating. In starter "C" L. brevis, L. plantarum and L. alimentarius predominated.

Protection by fungal starters against growth and secondary metabolite production of fungal spoilers of cheese.

PubMed

Nielsen, M S; Frisvad, J C; Nielsen, P V

1998-06-30

The influence of fungal starter cultures on growth and secondary metabolite production of fungal contaminants associated with cheese was studied on laboratory media and Camembert cheese. Isolates of the species Penicillium nalgiovense, P. camemberti, P. roqueforti and Geotrichum candidum were used as fungal starters. The species P. commune, P. caseifulvum, P. verrucosum, P. discolor, P. solitum, P. coprophilum and Aspergillus versicolor were selected as contaminants. The fungal starters showed different competitive ability on laboratory media and Camembert cheese. The presence of the Penicillium species, especially P. nalgiovense, showed an inhibitory effect on the growth of the fungal contaminants on laboratory media. G. candidum caused a significant inhibition of the fungal contaminants on Camembert cheese. The results indicate that G. candidum plays an important role in competition with undesirable microorganisms in mould fermented cheeses. Among the starters, P. nalgiovense caused the largest reduction in secondary metabolite production of the fungal contaminants on the laboratory medium. On Camembert cheese no significant changes in metabolite production of the fungal contaminants was observed in the presence of the starters.

Autochthonous fermentation starters for the industrial production of Negroamaro wines.

PubMed

Tristezza, Mariana; Vetrano, Cosimo; Bleve, Gianluca; Grieco, Francesco; Tufariello, Maria; Quarta, Angela; Mita, Giovanni; Spano, Giuseppe; Grieco, Francesco

2012-01-01

The aim of the present study was to establish a new procedure for the oenological selection of Saccharomyces cerevisiae strains isolated from natural must fermentations of an important Italian grape cultivar, denoted as "Negroamaro". For this purpose, 108 S. cerevisiae strains were selected as they did not produce H(2)S and then assayed by microfermentation tests. The adopted procedure made it possible to identify 10 strains that were low producers of acetic acid and hydrogen sulphide and showed that they completed sugar consumption during fermentation. These strains were characterized for their specific oenological and technological properties and, two of them, strains 6993 and 6920, are good candidates as industrial starter cultures. A novel protocol was set up for their biomass production and they were employed for industrial-scale fermentation in two industrial cellars. The two strains successfully dominated the fermentation process and contributed to increasing the wines' organoleptic quality. The proposed procedure could be very effective for selecting "company-specific" yeast strains, ideal for the production of typical regional wines. "Winery" starter cultures could be produced on request in a small plant just before or during the vintage season and distributed as a fresh liquid concentrate culture.

Lactose-free frozen yogurt: production and characteristics.

PubMed

Skryplonek, Katarzyna; Gomes, David; Viegas, Jorge; Pereira, Carlos; Henriques, Marta

2017-01-01

Nowadays, consumer demand is driving better and more nutritious dairy products. Changing from traditional to new lactose-free products poses technological challenges for the food industry in order to maintain or improve their food characteristics and consumer preferences. This study investigates the production of lactose-free frozen yogurt by enzymati- cally hydrolysis of lactose, and its influence on the final product characteristics. In the case of lactose-free products, commercial Ha-lactase® was used for hydrolysis, and the reaction occurred simultaneously with fermentation. The effect of lactose hydrolysis on the physicochemical properties, texture, viscosity, overrun and sensory attributes in the final product was investigated. After yogurt maturation, the acidity of the lactose-free product was significantly higher than in the control, suggesting that breaking down lactose enhances the fermentation process. Lactose-free frozen yogurt had significantly lower hardness and stickiness and higher viscosity than control frozen yogurt. Moreover, lactose hydrolysis promoted a smooth and creamy consistency, whereas in the case of conventional prod- ucts a coarse structure, due to the presence of large ice crystals, was identified. Hydrolysis of lactose also improved the sweetness and brightness of frozen yogurt. The improved textural properties of lactose-free product results from the fact that monosaccharides produced during lactose hydrolysis depress the freezing point of the mix, which enables product with softer structure and bigger resistance to ice recrystallization to be obtained. The study showed that lactose-free frozen yogurt may be used successfully for production of novel lactose-free frozen desserts. Lactose hydrolysis improves the texture and viscosity of the product,     as well as enhancing its sensory quality.

Species diversity and metabolic impact of the microbiota are low in spontaneously acidified Belgian sausages with an added starter culture of Staphylococcus carnosus.

PubMed

Janssens, M; Myter, N; De Vuyst, L; Leroy, F

2012-04-01

Quality of fermented sausages is affected by acidifying lactic acid bacteria (LAB) and colour- and flavour-promoting coagulase-negative staphylococci (CNS), whether or not used as starter culture. Artisan fermented sausages are often perceived as superior to industrial variants, partially because of the specific microbiota due to spontaneous acidification, which may be considered as an artisan characteristic. Therefore, two kinds of spontaneously acidified Belgian sausages were prepared (Belgian-type salami and Boulogne sausage), but with addition of a Staphylococcus carnosus culture. The Belgian-type salami was made from pork and beef, whereas the Boulogne sausage contained pork and horse meat. In all cases, Lactobacillus sakei was the dominant LAB species present on the raw materials and during fermentation, whereas enterococci remained present in the background. Enterobacteriaceae vanished after fermentation. The CNS species diversity on the raw materials was large and differed between the pork, beef, and horse meat. Nevertheless, this species diversity was annihilated during fermentation by the added S. carnosus culture. The volatiles fraction was mainly composed of aldehydes that originated from lipid oxidation and spices-derived compounds. Aromatic compounds that are typically associated to CNS activity, such as end-products from the metabolism of branched-chain amino acids, were not present in the Belgian-type salami and only marginally present in the Boulogne sausage. In conclusion, spontaneous acidification of Belgian-type fermented sausages leads to dominance of L. sakei and is no guarantee for bacterial contribution to the aroma profile when S. carnosus is added as a starter culture. Copyright © 2011 Elsevier Ltd. All rights reserved.

Development of buckwheat and teff sourdoughs with the use of commercial starters.

PubMed

Moroni, Alice V; Arendt, Elke K; Morrissey, John P; Dal Bello, Fabio

2010-08-15

In this study we investigated the suitability of commercial starters for the production of gluten free sourdoughs. For this purpose, four different laboratory scale sourdoughs were developed from the flours buckwheat or teff. Two different starters (SA, SB) were used to start the fermentations, which were carried out under two technological conditions. Sourdoughs were propagated by back-slopping until the stability was reached. The composition of the stable sourdoughs was investigated by culture dependent techniques and the development of the dominant biota was monitored by PCR-DGGE. Unique and complex LAB and yeasts communities were detected in each sourdough, comprising strains which originated from the flours. The competitiveness of the starter LAB varied according to the substrate and the fermentation conditions applied. Among the LAB present in both SA and SB, L. helveticus and L. paracasei strains did not persist in buckwheat or teff sourdoughs. Lc. argentinum was competitive only in buckwheat sourdoughs, whereas L. reuteri persisted only in teff sourdough. L. fermentum and L. helveticus present in both starters dominated only the sourdoughs fermented at the higher temperature. Remarkably, the starter yeasts were outcompeted by spontaneous yeast strains, i.e. Kazachstania barnetti and Saccharomyces cerevisiae in teff sourdoughs, whereas no yeasts were isolated from buckwheat sourdoughs. The isolation of autochthonous LAB and yeasts from the stable teff and buckwheat sourdoughs indicates that both flours represent an important reservoir for the isolation of novel and competitive starters for the production of gluten free sourdough bread. Copyright 2010 Elsevier B.V. All rights reserved.

Comparison of Bacterial Diversity Between Two Traditional Starters and the Round-Koji-Maker Starter for Traditional Cantonese Chi-Flavor Liquor Brewing

PubMed Central

Wang, Jie; Zhong, Qingping; Yang, Yingying; Li, Hanrong; Wang, Li; Tong, Yigang; Fang, Xiang; Liao, Zhenlin

2018-01-01

Xiaoqu is a traditional fermentation starter that is used for Chinese liquor production. Although microorganisms in the starters are closely associated with the quality and flavor of liquor, knowledge of the microbiota in xiaoqu is still far from complete, let alone the starters produced by new processes. Here, Illumina MiSeq high-throughput sequencing was applied to study bacterial composition in three types of xiaoqu used in Cantonese soybean-flavor (Chi-flavor) liquor, namely two traditional starters (Jiu Bing and Bing Wan) and a Round-Koji-maker starter (San qu) produced by the automatic starter-making disk machine. The results showed bacterial diversity in traditional starters was similar and higher than that in the Round-Koji-maker starter. Lactobacillus and Pediococcus were the dominant genera in all starters, while other different dominant genera also existed in different starters, which were Weissella, Acetobacter, and Gluconobacter for Jiu Bing, Weissella for Bing Wan, and Bacillus, Acetobacter, Acinetobacter and Klebsiella for San qu, respectively. Meanwhile, Cytophagaceae, one particular microbial family, and some pathogens including Klebsiella, Cronobacter, and Enterobacter were also found in San qu, indicating the automatic starter-making disk machine should be ameliorated before applied into industrial production. These results enriched our knowledge on xiaoqu-related microorganisms and might be helpful in industrial Chi-flavor liquor production and the development of fermentation technology. PMID:29875758

Comparison of Bacterial Diversity Between Two Traditional Starters and the Round-Koji-Maker Starter for Traditional Cantonese Chi-Flavor Liquor Brewing.

PubMed

Wang, Jie; Zhong, Qingping; Yang, Yingying; Li, Hanrong; Wang, Li; Tong, Yigang; Fang, Xiang; Liao, Zhenlin

2018-01-01

Xiaoqu is a traditional fermentation starter that is used for Chinese liquor production. Although microorganisms in the starters are closely associated with the quality and flavor of liquor, knowledge of the microbiota in xiaoqu is still far from complete, let alone the starters produced by new processes. Here, Illumina MiSeq high-throughput sequencing was applied to study bacterial composition in three types of xiaoqu used in Cantonese soybean-flavor ( Chi -flavor) liquor, namely two traditional starters ( Jiu Bing and Bing Wan ) and a Round-Koji-maker starter ( San qu ) produced by the automatic starter-making disk machine. The results showed bacterial diversity in traditional starters was similar and higher than that in the Round-Koji-maker starter. Lactobacillus and Pediococcus were the dominant genera in all starters, while other different dominant genera also existed in different starters, which were Weissella, Acetobacter , and Gluconobacter for Jiu Bing, Weissella for Bing Wan , and Bacillus, Acetobacter, Acinetobacter and Klebsiella for San qu , respectively. Meanwhile, Cytophagaceae , one particular microbial family, and some pathogens including Klebsiella, Cronobacter , and Enterobacter were also found in San qu , indicating the automatic starter-making disk machine should be ameliorated before applied into industrial production. These results enriched our knowledge on xiaoqu -related microorganisms and might be helpful in industrial Chi -flavor liquor production and the development of fermentation technology.

Effect of ingestion of soy yogurt on intestinal parameters of rats fed on a beef-based animal diet

PubMed Central

Bedani, Raquel; Pauly-Silveira, Nadiége Dourado; Cano, Veridiana Soares Pereira; Valentini, Sandro Roberto; de Rossi, Graciela Font; Valdez, Elizeu Antonio

2011-01-01

The aim of this study was to investigate whether the ingestion of soy yogurt fermented with Enterococcus faecium CRL 183 would modify the intestinal count of enterococci, fecal pH and ammonia content in rats fed on a diet containing red meat. The rats were placed in 4 groups: for 60 days, group I was given a standard casein-based rodent feed and groups II-IV, the beef-based feed. From day 30, groups III-IV also received the following products: III) soy yogurt; IV) suspension of E. faecium CRL 183. At the start and on days 30 and 60, feces were collected for the determination of pH, ammonia content, count of enterococci and identification of their species. On day 60, rats were sacrificed and their colons also removed for count of enterococci and identification of their species. Rats that ingested soy yogurt showed no significant change (P<0.05) in fecal counts of Enterococcus spp., but, this rat group showed a higher count of E. faecium than rats that ingested suspension of E. faecium CRL 183. The ingestion of soy yogurt and E. faecium culture caused a significant rise (P < 0.05) in fecal pH and ammonia content. Our results suggest that consumption of soy yogurt fermented with E. faecium CRL 183 and L. helveticus subsp. jugurti could change the species of Enterococcus spp. present in the feces and colon of rats fed on a beef-based diet. However, the fermented soy product and the pure culture of E. faecium CRL 183 also induced undesirable effects such as the increase of fecal pH and ammonia content in the feces of rats fed on a beef-based diet. PMID:24031747

Effect of thermal processing during yogurt production upon the detection of staphylococcal enterotoxin B.

PubMed

Principato, Maryann; Boyle, Thomas; Njoroge, Joyce; Jones, Robert L; O'Donnell, Michael

2009-10-01

This research was conducted to examine the inherent properties of yogurt contaminated with staphylococcal enterotoxin B (SEB). Two types of yogurts were produced for this study. Type I yogurts were produced by adding SEB at the start of yogurt production, and type II yogurts were produced by adding SEB after the milk base had been boiled. Biochemical characteristics inherent to yogurt, including pH, lactic acid and acetaldehyde concentrations, were analyzed weekly for each batch beginning at a time just after production and throughout a storage period of at least 4 weeks. The presence of toxin during yogurt production did not result in any significant biochemical or physical changes in yogurt. However, we were unable to detect SEB toxin in type I yogurt using a commercially available enzyme-linked immunosorbent assay (ELISA). In contrast, SEB was easily detectable by our ELISA in type II yogurt samples. Higher levels of SEB were recovered from type II yogurt that had been stored for 1 week than from type II yogurt that had been stored for any other length of time. These results indicate that the biochemical characteristics of yogurt did not change significantly (relative to control yogurt) in the presence of either thermally processed SEB or native SEB. However, the ability to detect SEB by ELISA was dependent on whether the toxin had been processed.

Evaluation of freeze-dried kefir coculture as starter in feta-type cheese production.

PubMed

Kourkoutas, Y; Kandylis, P; Panas, P; Dooley, J S G; Nigam, P; Koutinas, A A

2006-09-01

The use of freeze-dried kefir coculture as a starter in the production of feta-type cheese was investigated. Maturation of the produced cheese at 4 degrees C was monitored for up to 70 days, and the effects of the starter culture, the salting method, and the ripening process on quality characteristics were studied. The use of kefir coculture as a starter led to increased lactic acid concentrations and decreased pH values in the final product associated with significantly higher conversion rates compared to salted rennet cheese. Determination of bacterial diversity at the end of the ripening process in salted kefir and rennet cheeses by denaturing gradient gel electrophoresis technology, based on both DNA and RNA analyses, suggested a potential species-specific inhibition of members of the genera Staphylococcus and Psychrobacter by kefir coculture. The main active microbial associations in salted kefir cheese appeared to be members of the genera Pseudomonas and Lactococcus, while in salted rennet cheese, Oxalobacteraceae, Janthinobacterium, Psychrobacter, and Pseudomonas species were noted. The effect of the starter culture on the production of aroma-related compounds responsible for cheese flavor was also studied by the solid-phase microextraction-gas chromatography-mass spectrometry technique. Kefir coculture also appeared to extend the shelf life of unsalted cheese. Spoilage of kefir cheese was observed on the 9th and 20th days of preservation at 10 and 5 degrees C, respectively, while spoilage in the corresponding rennet cheese was detected on the 7th and 16th days. Microbial counts during preservation of both types of unsalted cheese increased steadily and reached similar levels, with the exception of staphylococci, which were significantly lower in unsalted kefir cheese. All types of cheese produced with kefir as a starter were approved and accepted by the panel during the preliminary sensory evaluation compared to commercial feta-type cheese.

A combination of acid lactase from Aspergillus oryzae and yogurt bacteria improves lactose digestion in lactose maldigesters synergistically: A randomized, controlled, double-blind cross-over trial.

PubMed

de Vrese, Michael; Laue, Christiane; Offick, Birte; Soeth, Edlyn; Repenning, Frauke; Thoß, Angelika; Schrezenmeir, Jürgen

2015-06-01

Lactose digestion can be improved in subjects with impaired or completely absent intestinal lactase activity by administration of lactase preparations and particularly of acid lactase, which is active in the stomach, or by yogurt containing live lactic acid bacteria. It is the question, if lactose digestion can be further enhanced by combining these two approaches. We investigated in a randomised, placebo-controlled, double-blind, 5-arm crossover study on 24 lactose malabsorbers with variable degrees of lactase deficiency if different lactase preparations and freeze-dried yogurt culture affect gastrointestinal lactose digestion after consuming moderate amounts of lactose (12.5 g) by assessing hydrogen exhalation over 6 h. Furthermore, symptoms of lactose intolerance (excess gas production, abdominal pain, diarrhoea or nausea) were assessed using validated questionnaires. All preparations increased lactose digestion and reduced peak hydrogen exhalation by -27% (yogurt), -29/-33% (3300/9000 FCC(1) ((1) One FCC hydrolyses about 5 or 1.7-2.5 mg lactose in aquous solution or in (artificial) chyme, respectively, according to the FCC-III method of the Committee on Codex Specifications, Food and Nutrition Board, National Research Council. Food Chemicals Codex, 3rd edition. Washington, DC, National Academy Press, 1981 It cannot precisely be defined how much lactose can be hydrolysed in vivo by the consumption of a certain number of FCC units.) units acid lactase from Aspergillus oryzae) or -46%, respectively (3300 FCC units lactase plus yogurt culture combined), as compared with placebo (p < 0.001, Friedman test). The combination preparation had not only the strongest effect, but also showed the lowest variance in H(2)-exhalation values (less malabsorbers with no reduction of H(2)-exhalation) Apart from this, both the higher dose lactase and the combination preparation significantly reduced the symptoms most closely associated with H(2)-exhalation, namely flatulences and

Effects of the incorporation of cantaloupe pulp in yogurt: Physicochemical, phytochemical and rheological properties.

PubMed

Kermiche, F; Boulekbache-Makhlouf, L; Félix, M; Harkat-Madouri, L; Remini, H; Madani, K; Romero, A

2018-01-01

The therapeutic effects of cantaloupe are of great interest for the development of functional foods such as yogurt. In this study a new dairy product has been formulated by enriching natural yogurt with fruit cantaloupe (yogurt with cantaloupe puree, yogurt with dry cantaloupe and yogurt with dry cantaloupe and cantaloupe puree). Thus, composition (moisture, ash, lipids, proteins), including amino acid contents, lactic flora as well as rheological (viscoelasticity, viscosity) property of cantaloupe yogurt and natural yogurt is assessed. In addition, pH value, water holding capacity and antioxidant activity (reducing power) are measured over refrigerated storage time. There are significant differences between natural yogurt and cantaloupe yogurt in almost all parameters. The results show that the pH decreases during the storage period and the antioxidant activity as well as the water holding capacity are more remarkable in the yogurt with dry cantaloupe at the 14th and the 28th day of storage, respectively. The addition of cantaloupe in natural yogurt ameliorates the load of lactic flora and modifies the rheological property of the new products. The results of the current study show that the addition of cantaloupe to yogurt significantly improved its quality.

Effect of starter cultures and packaging methods on amino acid profile and eating quality characteristics of pork ham.

PubMed

Gogoi, Protiva; Borpuzari, R N; Borpuzari, T; Hazarika, R A; Bora, J R

2015-08-01

Wet cured pork hams were inoculated with a mixed starter cultures comprising of Lactobacillus acidophilus and Micrococcus varians M483 at the dose level of 106 cfu/g and the un inoculated hams served as controls. The amino acid profile of hams of the treated and the control groups stored at 4oC under MAP and VP and evaluated on 60th day of storage revealed that treated hams liberated higher concentration of free amino acids except for proline and methionine which were found in higher concentration (P < 0.01) in the MAP control samples. The MAP control samples liberated glutamic acid (85.65 ± 1.40 ppm), cystine (21.56 ± 1.14 ppm) and tyrosine (16.63 ± 1.94 ppm) whereas, the treated samples did not release these amino acids. The VP control samples too liberated cystine (6.98 ± 1.36 ppm) and arginine (42.70 ± 2.78 ppm) but the treated ham of the VP did not liberate these amino acids. The VP hams had higher concentration (P < 0.01) of free proline, glycine, alanine, valine, methionine, isoleucine, phenylalanine, lysine and histidine than the MAP samples. Colour analysis of ham using CIE Lab colour system revealed that the treated samples had significantly higher concentrations of L*, a* and b* components. The L* and a* values were higher in the MAP than under VP systems while the b* values were higher in the VP samples than the MAP samples. Neither the bacterial cultures nor the packaging system influenced the textural property of ham. Starter cultures inoculated hams were rated superior (P < 0.05) in terms of their sensory properties. Hams packaged under MAP were rated superior (P < 0.05) than those packaged under VP in terms of appearance, colour, taste, tenderness, flavour, juiciness and overall acceptability.

PH-sensing 96-well microtitre plates for the characterization of acid production by dairy starter cultures.

PubMed

John, Gernot T; Goelling, Detlef; Klimant, Ingo; Schneider, Holger; Heinzle, Elmar

2003-08-01

A new method for characterization of acid production by dairy starter cultures is presented. Microplates with integrated optical pH sensors are developed. Two fluorophores, a pH-sensitive and a pH-insensitive one are immobilised at the bottom of a polystyrene 96-well microtitre plate. The pH-insensitive fluorophore serves as an internal reference and makes calibration unnecessary. The sensor measures pH accurately in optically well-defined media. Particles and fluorophores contained in the bulk medium disturbed the measurements. Despite these disturbances it was possible to clearly sense differences in inoculum type and in inoculum sizes of cultures of Lactococcus lactis and of Streptococcus thermophilus at 30 and 37 degrees C. Besides a pH-related signal there is information about other changes during milk fermentation. The cultivation results were compared with those from the established CINAC-method. From this comparison it can be concluded that the new method can be used reliably to characterize particularly a large number of strains for screening purposes but also for quality control.

Modeling Lactic Fermentation of Gowé Using Lactobacillus Starter Culture.

PubMed

de J C Munanga, Bettencourt; Loiseau, Gérard; Grabulos, Joël; Mestres, Christian

2016-12-01

A global model of the lactic fermentation step of gowé was developed by assembling blocks hosting models for bacterial growth, lactic acid production, and the drop of pH during fermentation. Commercial strains of Lactobacillus brevis and of Lactobacillus plantarum were used; their growth was modeled using Rosso's primary model and the gamma concept as a secondary model. The optimum values of pH and temperature were 8.3 ± 0.3, 44.6 ± 1.2 °C and 8.3 ± 0.3, 3.2 ± 37.1 °C with μ max values of 1.8 ± 0.2 and 1.4 ± 0.1 for L. brevis and L. plantarum respectively. The minimum inhibitory concentration of undissociated lactic acid was 23.7 mM and 35.6 mM for L. brevis and L. plantarum , respectively. The yield of lactic acid was five times higher for L. plantarum than for L. brevis , with a yield of glucose conversion to lactic acid close to 2.0 for the former and 0.8 for the latter. A model was developed to predict the pH drop during gowé fermentation. The global model was partially validated during manufacturing of gowé. The global model could be a tool to aid in the choice of suitable starters and to determine the conditions for the use of the starter.

Lactose digestion by yogurt beta-galactosidase: influence of pH and microbial cell integrity.

PubMed

Martini, M C; Bollweg, G L; Levitt, M D; Savaiano, D A

1987-02-01

Lactase-deficient subjects more effectively digest lactose in yogurt than lactose in other dairy products, apparently due to yogurt microbial beta-galactosidase (beta-gal) which is active in the GI tract. We evaluated the effects of buffering capacity of yogurt, gastric pH, and microbial cell disruption on beta-gal activity and lactose digestion. Three times more acid was required to acidify yogurt than to acidify milk. Yogurt beta-gal was stable at pH 4.0 but inactivated at lower pH. When yogurt was sonicated to disrupt microbial cell structure, only 20% activity remained after incubation at pH 4.0 for 60 min. In vivo gastric pH remained greater than 2.7 for 3 h after ingestion of yogurt. Acidified milk alone or with disrupted yogurt microorganisms caused twice as much lactose malabsorption as did acidified milk containing intact yogurt microorganisms. The results provide a possible explanation for the survival of beta-gal activity from yogurt in the GI tract.

Evaluation of tilapia skin gelatin as a mammalian gelatin replacer in acid milk gels and low-fat stirred yogurt.

PubMed

Pang, Zhihua; Deeth, Hilton; Yang, Hongshun; Prakash, Sangeeta; Bansal, Nidhi

2017-05-01

Tilapia skin gelatin (TSG) was studied in a 3-stage process (cooling, annealing, and heating) for pure gelatin gels and in a 4-stage process (acidification, cooling, annealing, and heating) for acid milk gels and cultured yogurt. The aim was to evaluate the use of TSG as a replacement for mammalian gelatin in yogurt. In pure TSG gels, stronger gels with higher melting temperatures were formed with increasing TSG concentrations. Compared with bovine gelatin (BG), which gelled at a concentration of 2.5%, TSG gels had lower gelling (14.1°C) and melting (24°C) temperatures but comparable storage moduli during annealing. In acid milk gels, addition of TSG increased the firmness of the gels with increasing concentration. Gelling and melting points of TSG in milk gels were observed at sufficient concentrations during cooling and heating. Strands and sheets were observed in the electron micrographs of milk gels with 1% TSG and a very dense structure was observed with 2.5% TSG. Yogurt with 0.4% TSG had similar viscosity, consistency, pseudoplasticity, and thixotropy as yogurt containing 0.4% BG; no difference was perceived by sensory panelists according to a triangle test. Addition of 0.4% TSG completely prevented whey separation from the acid milk gel and yogurt. The results suggest that TSG could be a suitable replacement for mammalian gelatin in low-fat stirred yogurt. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Starter cultures as biocontrol strategy to prevent Brettanomyces bruxellensis proliferation in wine.

PubMed

Berbegal, Carmen; Spano, Giuseppe; Fragasso, Mariagiovanna; Grieco, Francesco; Russo, Pasquale; Capozzi, Vittorio

2018-01-01

Brettanomyces bruxellensis is a common and significant wine spoilage microorganism. B. bruxellensis strains generally detain the molecular basis to produce compounds that are detrimental for the organoleptic quality of the wine, including some classes of volatile phenols that derive from the sequential bioconversion of specific hydroxycinnamic acids such as ferulate and p-coumarate. Although B. bruxellensis can be detected at any stage of the winemaking process, it is typically isolated at the end of the alcoholic fermentation (AF), before the staring of the spontaneous malolactic fermentation (MLF) or during barrel aging. For this reason, the endemic diffusion of B. bruxellensis leads to consistent economic losses in the wine industry. Considering the interest in reducing sulfur dioxide use during winemaking, in recent years, biological alternatives, such as the use of tailored selected yeast and bacterial strains inoculated to promote AF and MLF, are actively sought as biocontrol agents to avoid the "Bretta" character in wines. Here, we review the importance of dedicated characterization and selection of starter cultures for AF and MLF in wine, in order to reduce or prevent both growth of B. bruxellensis and its production of volatile phenols in the matrix.

The effect of Isabel grape addition on the physicochemical, microbiological and sensory characteristics of probiotic goat milk yogurt.

PubMed

Silva, Francyeli Araújo; de Oliveira, Maria Elieidy Gomes; de Figueirêdo, Rossana Maria Feitosa; Sampaio, Karoliny Brito; de Souza, Evandro Leite; de Oliveira, Carlos Eduardo Vasconcelos; Pintado, Maria Manuela Estevez; Ramos do Egypto Queiroga, Rita de Cássia

2017-06-21

Goat milk is an attractive food because of its nutritional properties, easy digestibility and hypoallergenicity. Goat milk yogurt is an appropriate matrix for the inclusion of new ingredients such as probiotic cultures, fruit and its derivatives. Grapes are rich in polyphenols and recognized for their health benefits. The aim of this study was to improve the quality characteristics of probiotic goat milk yogurt by the addition of an Isabel grape (Vitis labrusca L.) preparation (IGP). For this, the influence of the addition of IGP on the physicochemical, microbiological and sensory characteristics of goat milk yogurt containing the probiotic Lactobacillus acidophilus LA-05 was evaluated during 28 days of refrigerated storage (5 ± 0.5 °C). Four yogurt formulations were prepared, each varying in the added IGP amount, as follows: Y0 (not containing IGP), YG15 (containing 15 g per 100 mL of IGP), YG20 (containing 20 g per 100 mL of IGP), and YG25 (containing 25 g per 100 mL of IGP). All formulations showed probiotic counts ranging from 7 to 8 log CFU mL -1 over the assessed storage period. The addition of 20 g per 100 mL of IGP affected positively the colour, viscosity, and sensory acceptance of the yogurt formulations. The production of goat milk yogurt containing L. acidophilus LA-05 and IGP is an option for developing a new goat dairy product with added value due to the inclusion of components with potential functional properties.

Effect of purified oat β-glucan on fermentation of set-style yogurt mix.

PubMed

Singh, Mukti; Kim, Sanghoon; Liu, Sean X

2012-08-01

Effect of oat β-glucan on the fermentation of set-style yogurt was investigated by incorporating 0%, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% of purified oat β-glucan into the yogurt mix. It was found that levels up to 0.3% resulted in yogurts with quality characteristics similar to the control yogurt. Higher levels of β-glucan however retarded the fermentation process with noticeable difference in the characteristics of the yogurt. Examination of the morphologies of yogurt with and without β-glucan revealed that β-glucan formed aggregates with casein micelle and did not form phase-separated domains. This research demonstrated that β-glucan could be added to yogurt up to 0.3%, which meets the nutrient guidelines, to have added nutritional benefits. Yogurt is known for its beneficial effects on human health and nutrition. Yogurt production and consumption is increasing in the United States every year. However, it is lacking in β-glucans, which are recognized for their nutritional importance as functional bioactive ingredients. The main objective was to develop and characterize low-fat yogurts with added β-glucan. This research demonstrated that β-glucan could be added to yogurt up to 0.3%, which meets the nutrient guidelines for added nutritional benefits, without affecting the characteristics of yogurt significantly. This study will benefit the dairy industry by generating new products offering healthy alternatives. Journal of Food Science © 2012 Institute of Food Technologists® No claim to original US government works.

Study of Vis/NIR spectroscopy measurement on acidity of yogurt

NASA Astrophysics Data System (ADS)

He, Yong; Feng, Shuijuan; Wu, Di; Li, Xiaoli

2006-09-01

A fast measurement of pH of yogurt using Vis/NIR-spectroscopy techniques was established in order to measuring the acidity of yogurt rapidly. 27 samples selected separately from five different brands of yogurt were measured by Vis/NIR-spectroscopy. The pH of yogurt on positions scanned by spectrum was measured by a pH meter. The mathematical model between pH and Vis/NIR spectral measurements was established and developed based on partial least squares (PLS) by using Unscramble V9.2. Then 25 unknown samples from 5 different brands were predicted based on the mathematical model. The result shows that The correlation coefficient of pH based on PLS model is more than 0.890, and standard error of calibration (SEC) is 0.037, standard error of prediction (SEP) is 0.043. Through predicting the pH of 25 samples of yogurt from 5 different brands, the correlation coefficient between predictive value and measured value of those samples is more than 0918. The results show the good to excellent prediction performances. The Vis/NIR spectroscopy technique had a significant greater accuracy for determining the value of pH. It was concluded that the VisINIRS measurement technique can be used to measure pH of yogurt fast and accurately, and a new method for the measurement of pH of yogurt was established.

Yogurt consumption and impact on health: focus on children and cardiometabolic risk.

PubMed

Marette, André; Picard-Deland, Eliane

2014-05-01

An accumulating body of epidemiologic data, clinical trials, and mechanistic studies suggests that yogurt consumption as part of a healthy diet may be beneficial to cardiometabolic health. This brief review focuses on children and adolescents, introducing new concepts underlying the effect of yogurt consumption on body weight maintenance and the prevention of cardiovascular diseases. Specific properties of yogurt are discussed, which highlight that yogurt is an easy-to-digest, nutrient-dense, and satiating food that contains high-quality protein and specific amino acids. Moreover, the role of yogurt as a modulator of the gut microbiota in infancy is explored. We also propose the idea that the specific matrix of yogurt has bioavailability and metabolic properties that can be exploited to increase the functionality of this dairy product.

Antibacterial Effects against Various Foodborne Pathogens and Sensory Properties of Yogurt Supplemented with Panax ginseng Marc Extract

PubMed Central

Eom, Su Jin; Hwang, Ji Eun; Kim, Kee-Tae; Paik, Hyun-Dong

2017-01-01

Panax ginseng marc is produced from fresh ginseng roots during processing and is generally treated as industrial waste. The primary aim of this study was to improve its utilization in the dairy industry as a potential high-value resource. Yogurt was prepared from 11% skim milk powder, 0.1% pectin, 10% sucrose, and ginseng marc ethanol extract (GME, 0.5% and 1.0%) in milk, and was inoculated with a 0.02% yogurt culture (Lactobacillus acidophilus, Bifidobacterium longum, and Streptococcus thermophilus). After fermentation at 40°C for 6-8 h, the physicochemical properties of samples were analyzed by the AOAC, Kjeldahl, and Soxhlet methods. Sensory evaluation was performed based on consumer acceptability scores with a 7-point scale, and antimicrobial effects were measured by the agar plate method. The moisture, crude protein, crude fat, and ash contents of yogurt supplemented with 1% GME were 85.06±0.06%, 4.41±0.01%, 4.30±0.05%, and 0.81±0.03%, respectively, with no significant changes noted from those of yogurt without GME (control), except for an increase in the crude fat content. The sensory scores of color, flavor, texture, overall taste, and overall acceptance of yogurt supplemented with below 1% GME did not differ significantly (p<0.05) to those of the control yogurt. In addition, the growths of Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Escherichia coli, and Enterobacter sakazakii were inhibited during fermentation and storage. These results suggest that GME could be used in dairy products as a supplement and in the food industry as an antimicrobial material. PMID:29147103

Effects of copper supplement on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture.

PubMed

Rodríguez, L Mato; Alatossava, T

2008-10-01

To determine the effects of supplemented copper (Cu2+) on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture. Thirteen strains belonging to Lactobacillus delbrueckii, Lactobacillus helveticus, Lactobacillus rhamnosus, Streptococcus thermophilus or Propionibacterium freudenreichii species were exposed to various copper concentrations in the proper growth medium at relevant growth temperatures, and the effects of supplemented copper on bacterial growth and cell viability were determined by optical density and pH measurements, also by platings. Among the species considered, L. delbrueckii was the most copper resistant and S. thermophilus the most sensitive to copper. Anaerobic conditions increased this sensitivity significantly. There was also a considerable amount of variation in copper resistance at strain level. Copper resistance is both a species- and strain-dependent property and may reflect variability in copper-binding capacities by cell wall components among species and strains. In addition, the chemical state of copper may be involved. This study revealed that copper resistance is a highly variable property among starter and adjunct strains, and this variability should be considered when strains are selected for Emmental cheese manufacture.

Survival of Yogurt Bacteria in the Human Gut

PubMed Central

Elli, Marina; Callegari, Maria Luisa; Ferrari, Susanna; Bessi, Elena; Cattivelli, Daniela; Soldi, Sara; Morelli, Lorenzo; Goupil Feuillerat, Nathalie; Antoine, Jean-Michel

2006-01-01

Whether Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus can be recovered after passage through the human gut was tested by feeding 20 healthy volunteers commercial yogurt. Yogurt bacteria were found in human feces, suggesting that they can survive transit in the gastrointestinal tract. PMID:16820518

Physicochemical and sensory properties of yogurt enriched with microencapsulated fish oil.

PubMed

Tamjidi, F; Nasirpour, A; Shahedi, M

2012-08-01

Encapsulation of marine omega-3 oil by complex coacervation technique has been introduced as most effective approach to delay its oxidation and extend shelf life of ω(3)-enriched food products. Therefore, to produce enriched yogurt, fish oil containing long-chain omega-3 polyunsaturated fatty acids was microencapsulated in complex coacervates of gelatin/acacia gum. Then, the microcapsules were dried and their surface oil was extracted. Set yogurt was prepared by enriched milk with microcapsules powder. Physicochemical and sensory properties of enriched yogurt were measured during 21 days storage. Acidity, apparent viscosity and water holding capacity of enriched samples were higher and gel strength and amount of whey separation were lower compared to the control. The enriched yogurt samples were more yellowish compared to control. The peroxide value of free and encapsulated fish oil in enriched yogurt samples, after 22 days storage, were increased to 72% and 260%, respectively. Fish oil release of microcapsules was not detected by gas chromatography in extracted oil from enriched yogurt. Sensory results showed that untrained panelists evaluated overall acceptance of enriched yogurt with treated-fish oil microcapsules by lime juice as 'neither liked nor disliked to slightly liked'.

Is yogurt intake associated with periodontitis due to calcium?

PubMed

Kim, Hye-Sung; Kim, Young-Youn; Oh, Jeong-Kyu; Bae, Kwang-Hak

2017-01-01

The purpose of this study is to determine whether the lower intakes of yogurt, milk, and calcium are associated with periodontitis in a nationally representative sample of Korean adults. This study comprised 6,150 adults 19 or more years old who took both periodontal examination and nutrition survey. The frequency of yogurt and milk intake was examined with a food frequency questionnaire. The amount of calcium intake was calculated with dietary intakes data gained from complete one-day 24-hour recall interviews. Periodontitis was assessed using the Community Periodontal Index (CPI). Multivariate logistic regression analyses were performed for the whole sample and subgroups with the strata of age, gender, or smoking, in a complex sampling design. Less intake of yogurt was significantly associated with periodontitis (odds ratio [OR] 0.82, 95% confidential interval [CI] 0.70-0.97), but neither less intake of milk (OR 1.04, 95% CI 0.89-1.20) nor lower intake of calcium (OR 1.04, 95% CI 0.89-1.21) was significantly associated with periodontitis. In the subgroup analysis, no difference in the association of yogurt intake with periodontitis was found according to the strata of age, gender, and smoking. In conclusion, periodonitis was significantly associated with the less intake of yogurt among the Korean adults, but the calcium contained in yogurt is not likely to cause it.

Is yogurt intake associated with periodontitis due to calcium?

PubMed Central

Kim, Hye-Sung; Kim, Young-Youn; Oh, Jeong-Kyu

2017-01-01

The purpose of this study is to determine whether the lower intakes of yogurt, milk, and calcium are associated with periodontitis in a nationally representative sample of Korean adults. This study comprised 6,150 adults 19 or more years old who took both periodontal examination and nutrition survey. The frequency of yogurt and milk intake was examined with a food frequency questionnaire. The amount of calcium intake was calculated with dietary intakes data gained from complete one-day 24-hour recall interviews. Periodontitis was assessed using the Community Periodontal Index (CPI). Multivariate logistic regression analyses were performed for the whole sample and subgroups with the strata of age, gender, or smoking, in a complex sampling design. Less intake of yogurt was significantly associated with periodontitis (odds ratio [OR] 0.82, 95% confidential interval [CI] 0.70–0.97), but neither less intake of milk (OR 1.04, 95% CI 0.89–1.20) nor lower intake of calcium (OR 1.04, 95% CI 0.89–1.21) was significantly associated with periodontitis. In the subgroup analysis, no difference in the association of yogurt intake with periodontitis was found according to the strata of age, gender, and smoking. In conclusion, periodonitis was significantly associated with the less intake of yogurt among the Korean adults, but the calcium contained in yogurt is not likely to cause it. PMID:29084251

Peptide profiling of bovine kefir reveals 236 unique peptides released from caseins during its production by starter culture or kefir grains.

PubMed

Ebner, Jennifer; Aşçı Arslan, Ayşe; Fedorova, Maria; Hoffmann, Ralf; Küçükçetin, Ahmet; Pischetsrieder, Monika

2015-03-18

Kefir has a long tradition in human nutrition due to its presupposed health promoting effects. To investigate the potential contribution of bioactive peptides to the physiological effects of kefir, comprehensive analysis of the peptide profile was performed by nano-ESI-LTQ-Orbitrap MS coupled to nano-ultrahigh-performance liquid chromatography. Thus, 257 peptides were identified, mainly released from β-casein, followed by αS1-, κ-, and αS2-casein. Most (236) peptides were uniquely detected in kefir, but not in raw milk indicating that the fermentation step does not only increase the proteolytic activity 1.7- to 2.4-fold compared to unfermented milk, but also alters the composition of the peptide fraction. The influence of the microflora was determined by analyzing kefir produced from traditional kefir grains or commercial starter culture. Kefir from starter culture featured 230 peptide sequences and showed a significantly, 1.4-fold higher proteolytic activity than kefir from kefir grains with 127 peptides. A match of 97 peptides in both varieties indicates the presence of a typical kefir peptide profile that is not influenced by the individual composition of the microflora. Sixteen of the newly identified peptides were previously described as bioactive, including angiotensin-converting enzyme (ACE)-inhibitory, antimicrobial, immunomodulating, opioid, mineral binding, antioxidant, and antithrombotic effects. The present study describes a comprehensive peptide profile of kefir comprising 257 sequences. The peptide list was used to identify 16 bioactive peptides with ACE-inhibitory, antioxidant, antithrombotic, mineral binding, antimicrobial, immunomodulating and opioid activity in kefir. Furthermore, it was shown that a majority of the kefir peptides were not endogenously present in the raw material milk, but were released from milk caseins by proteases of the microbiota and are therefore specific for the product. Consequently, the proteolytic activity and the

Yogurt consumption and abdominal obesity reversion in the PREDIMED study.

PubMed

Santiago, S; Sayón-Orea, C; Babio, N; Ruiz-Canela, M; Martí, A; Corella, D; Estruch, R; Fitó, M; Aros, F; Ros, E; Gómez-García, E; Fiol, M; Lapetra, J; Serra-Majem, Ll; Becerra-Tomás, N; Salas-Salvadó, J; Pinto, X; Schröder, H; Martínez, J A

2016-06-01

Evidence on the association yogurt consumption and obesity is not conclusive. The aim of this study was to prospectively evaluate the association between yogurt consumption, reversion of abdominal obesity status and waist circumference change in elderly. 4545 individuals at high cardiovascular risk were prospectively followed. Total, whole-fat and low-fat yogurt consumption were assessed using food frequency questionnaires. Generalized estimating equations were used to analyze the association between yogurt consumption and waist circumference change (measured at baseline and yearly during the follow-up). Logistic regression models were used to evaluate the odds ratios (ORs) and 95% CIs of the reversion rate of abdominal obesity for each quintile of yogurt consumption compared with the lowest quintile. After multivariable adjustment, the average yearly waist circumference change in the quintiles of whole-fat yogurt consumption was: Q1: 0.00, Q2: 0.00 (-0.23 to 0.23), Q3: -0.15 (-0.42 to 0.13), Q4: 0.10 (-0.21 to 0.42), and Q5: -0.23 (-0.46 to -0.00) cm; p for trend = 0.05. The ORs for the reversion of abdominal obesity for whole-fat yogurt consumption were Q1: 1.00, Q2: 1.40 (1.04-1.90), Q3: 1.33 (0.94-1.89), Q4: 1.21 (0.83-1.77), and Q5: 1.43 (1.06-1.93); p for trend = 0.26. Total yogurt consumption was not significantly associated with reversion of abdominal obesity status and a lower waist circumference. However, consumption of whole-fat yogurt was associated with changes in waist circumference and higher probability for reversion of abdominal obesity. Therefore, it seems that whole-fat yogurt has more beneficial effects in management of abdominal obesity in elderly population at high cardiovascular risk. Copyright © 2015 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All

Impulse noise generated by starter pistols

PubMed Central

Meinke, Deanna K.; Finan, Donald S.; Soendergaard, Jacob; Flamme, Gregory A.; Murphy, William J.; Lankford, James E.; Stewart, Michael

2015-01-01

Objective This study describes signals generated by .22 and .32 caliber starter pistols in the context of noise-induced hearing loss risk for sports officials and athletes. Design Acoustic comparison of impulses generated from typical .22 and .32 caliber starter pistols firing blanks were made to impulses generated from comparable firearms firing both blanks and live rounds. Acoustic characteristics are described in terms of directionality and distance from the shooter in a simulated outdoor running track. Metrics include peak sound pressure levels (SPL), A-weighted equivalent 8-hour level (LeqA8), and maximum permissible number of individual shots, or maximum permissible exposures (MPE) for the unprotected ear. Results Starter pistols produce peak SPLs above 140 dB. The numbers of MPEs are as few as five for the .22-caliber starter pistol, and somewhat higher (≤25) for the .32-caliber pistol. Conclusion The impulsive sounds produced by starter pistols correspond to MPE numbers that are unacceptably small for unprotected officials and others in the immediate vicinity of the shooter. At the distances included in this study, the risk to athletes appears to be low (when referencing exposure criteria for adults), but the sound associated with the starter pistol will contribute to the athlete’s overall noise exposure. PMID:23373743

The future of yogurt: scientific and regulatory needs.

PubMed

German, J Bruce

2014-05-01

Lactation biology, microbial selection, and human diversity are central themes that could guide investment in scientific research, industrial innovation, and regulatory policy oversight to propel yogurt into the central role for health-promoting food products. The ability of yogurt to provide the nourishing properties of milk together with the live microorganisms from fermentation provides a unique combination of food assets. Academic research must now define the various targets on which these biological assets act to improve health and develop the metrics that can quantitatively document their benefits. The food industry must reconcile that yogurt and its microorganisms cannot be expected to provide measurable benefits for all consumers, at all doses, and at all times. A supportive regulatory oversight must demand safety and yet encourage innovations that support a value proposition for yogurt in health. Health valuation in the marketplace will be driven by parallel innovations, including accurate assessment technologies, validated microbial ingredients, and health-aware consumers.

Sensory evaluation of locally-grown fruit purees and inulin fibre on probiotic yogurt in Mwanza, Tanzania and the Microbial Analysis of Probiotic Yogurt Fortified with Moringa oleifera.

PubMed

Hekmat, Sharareh; Morgan, Kathryn; Soltani, Mohammad; Gough, Robert

2015-03-01

The purpose of this study was to establish new food products that increase the nutritional value and health benefits of the probiotic yogurt currently used in the Western Heads East (WHE) Project in Mwanza, Tanzania. The probiotic yogurt has established health benefits, and product development through fortification must not adversely affect the acceptability of yogurt or the viability of the probiotics. Both sensory testing and microbial analysis testing were conducted. The products tested were yogurt fortified with locally-grown fruit purees with inulin and Moringa oleifera. The results of the sensory evaluation showed that all yogurts were not rated significantly different from the control, except for appearance. The avocado puree without inulin rated significantly lower in all categories. The microbial analysis showed that Moringa oleifera did not negatively affect the growth of Lactobacillus rhamnosus GR-1 in MRS, milk or yogurt, although a significant decrease was found after 5 weeks of storage at 4 (o)C.

Sensory Evaluation of Locally-grown Fruit Purees and Inulin Fibre on Probiotic Yogurt in Mwanza, Tanzania and the Microbial Analysis of Probiotic Yogurt Fortified with Moringa oleifera

PubMed Central

Morgan, Kathryn; Soltani, Mohammad; Gough, Robert

2015-01-01

ABSTRACT The purpose of this study was to establish new food products that increase the nutritional value and health benefits of the probiotic yogurt currently used in the Western Heads East (WHE) Project in Mwanza, Tanzania. The probiotic yogurt has established health benefits, and product development through fortification must not adversely affect the acceptability of yogurt or the viability of the probiotics. Both sensory testing and microbial analysis testing were conducted. The products tested were yogurt fortified with locally-grown fruit purees with inulin and Moringa oleifera. The results of the sensory evaluation showed that all yogurts were not rated significantly different from the control, except for appearance. The avocado puree without inulin rated significantly lower in all categories. The microbial analysis showed that Moringa oleifera did not negatively affect the growth of Lactobacillus rhamnosus GR-1 in MRS, milk or yogurt, although a significant decrease was found after 5 weeks of storage at 4 oC. PMID:25995722

Selection of Yeasts as Starter Cultures for Table Olives: A Step-by-Step Procedure

PubMed Central

Bevilacqua, Antonio; Corbo, Maria Rosaria; Sinigaglia, Milena

2012-01-01

The selection of yeasts intended as starters for table olives is a complex process, including a characterization step at laboratory level and a validation at lab level and factory-scale. The characterization at lab level deals with the assessment of some technological traits (growth under different temperatures and at alkaline pHs, effect of salt, and for probiotic strains the resistance to preservatives), enzymatic activities, and some new functional properties (probiotic traits, production of vitamin B-complex, biological debittering). The paper reports on these traits, focusing both on their theoretical implications and lab protocols; moreover, there are some details on predictive microbiology for yeasts of table olives and on the use of multivariate approaches to select suitable starters. PMID:22666220

Modeling Lactic Fermentation of Gowé Using Lactobacillus Starter Culture

PubMed Central

de J. C. Munanga, Bettencourt; Loiseau, Gérard; Grabulos, Joël; Mestres, Christian

2016-01-01

A global model of the lactic fermentation step of gowé was developed by assembling blocks hosting models for bacterial growth, lactic acid production, and the drop of pH during fermentation. Commercial strains of Lactobacillus brevis and of Lactobacillus plantarum were used; their growth was modeled using Rosso’s primary model and the gamma concept as a secondary model. The optimum values of pH and temperature were 8.3 ± 0.3, 44.6 ± 1.2 °C and 8.3 ± 0.3, 3.2 ± 37.1 °C with μmax values of 1.8 ± 0.2 and 1.4 ± 0.1 for L. brevis and L. plantarum respectively. The minimum inhibitory concentration of undissociated lactic acid was 23.7 mM and 35.6 mM for L. brevis and L. plantarum, respectively. The yield of lactic acid was five times higher for L. plantarum than for L. brevis, with a yield of glucose conversion to lactic acid close to 2.0 for the former and 0.8 for the latter. A model was developed to predict the pH drop during gowé fermentation. The global model was partially validated during manufacturing of gowé. The global model could be a tool to aid in the choice of suitable starters and to determine the conditions for the use of the starter. PMID:27916901

Modeling the kinetics of survival of Staphylococcus aureus in regional yogurt from goat's milk.

PubMed

Bednarko-Młynarczyk, E; Szteyn, J; Białobrzewski, I; Wiszniewska-Łaszczych, A; Liedtke, K

2015-01-01

The aim of this study was to determine the kinetics of the survival of the test strain of Staphylococcus aureus in the product investigated. Yogurt samples were contaminated with S. aure to an initial level of 10(3)-10(4) cfu/g. The samples were then stored at four temperatures: 4, 6, 20, 22°C. During storage, the number of S. aureus forming colonies in a gram of yogurt was determined every two hours. Based on the results of the analysis culture the curves of survival were plotted. Three primary models were selected to describe the kinetics of changes in the count of bacteria: Cole's model, a modified model of Gompertz and the model of Baranyi and Roberts. Analysis of the model fit carried out based on the average values of Pearson's correlation coefficient, between the modeled and measured values, showed that the Cole's model had the worst fit. The modified Gompertz model showed the count of S. aureus as a negative value. These drawbacks were not observed in the model of Baranyi and Roberts. For this reason, this model best reflects the kinetics of changes in the number of staphylococci in yogurt.

Antifungal starter culture for packed bread: influence of two storage conditions.

PubMed

Gerez, Carla L; Fornaguera, María J; Obregozo, Mariano D; Font de Valdez, Graciela; Torino, María I

2015-01-01

In this study, we analyzed the conservation of a semi-liquid bio-preserver (SL778) developed with Lactobacillus plantarum CRL 778, a lactic acid bacterium (LAB) having antifungal activity. The characteristics of the SL778 starter remained stable during a 14-day storage at 4°C. At -20°C, cell viability and organic acid concentration showed a significant (p<0.05) decrease after 7 days. These differences observed between the storage temperatures tested were reflected in the acidification activity of SL778 during dough fermentation. However, SL778 maintained its antifungal efficacy up to a 14-day storage at both temperatures. Sensory attributes (acidic and spicy tastes and acidic smell) of breads manufactured with starter SL778 (stored at 4 or -20°C) were evaluated. No undesirable difference was detected with respect to bread control without SL778 and bread manufactured with SL778 (stored at 4 or -20°C). In conclusion, the SL778 semi-liquid bio-preserver can be stored at 4 or -20°C without modifying its antifungal activity during 14 days. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Stability of free and encapsulated Lactobacillus acidophilus ATCC 4356 in yogurt and in an artificial human gastric digestion system.

PubMed

Ortakci, F; Sert, S

2012-12-01

The objective of this study was to determine the effect of encapsulation on survival of probiotic Lactobacillus acidophilus ATCC 4356 (ATCC 4356) in yogurt and during artificial gastric digestion. Strain ATCC 4356 was added to yogurt either encapsulated in calcium alginate or in free form (unencapsulated) at levels of 8.26 and 9.47 log cfu/g, respectively, and the influence of alginate capsules (1.5 to 2.5mm) on the sensorial characteristics of yogurts was investigated. The ATCC 4356 strain was introduced into an artificial gastric solution consisting of 0.08 N HCl (pH 1.5) containing 0.2% NaCl or into artificial bile juice consisting of 1.2% bile salts in de Man, Rogosa, and Sharpe broth to determine the stability of the probiotic bacteria. When incubated for 2h in artificial gastric juice, the free ATCC 4356 did not survive (reduction of >7 log cfu/g). We observed, however, greater survival of encapsulated ATCC 4356, with a reduction of only 3 log cfu/g. Incubation in artificial bile juice (6 h) did not significantly affect the viability of free or encapsulated ATCC 4356. Moreover, statistically significant reductions (~1 log cfu/g) of both free and encapsulated ATCC 4356 were observed during 4-wk refrigerated storage of yogurts. The addition of probiotic cultures in free or alginate-encapsulated form did not significantly affect appearance/color or flavor/odor of the yogurts. However, significant deficiencies were found in body/texture of yogurts containing encapsulated ATCC 4356. We concluded that incorporation of free and encapsulated probiotic bacteria did not substantially change the overall sensory properties of yogurts, and encapsulation in alginate using the extrusion method greatly enhanced the survival of probiotic bacteria against an artificial human gastric digestive system. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of purified oat ß-glucan on fermentation of set-style yogurt mix

USDA-ARS?s Scientific Manuscript database

Effect of ß-glucan on the fermentation of set-style yogurt was investigated by incorporating 0, 0.1, 0.2, 0.3, 0.4, and 0.5% of ß-glucan into the yogurt mix. It was found that levels up to 0.3% resulted in yogurts with quality characteristics similar to the control yogurt. Higher levels of ß-gluca...

Autochthonous starter cultures and indigenous grape variety for regional wine production.

PubMed

Garofalo, C; El Khoury, M; Lucas, P; Bely, M; Russo, P; Spano, G; Capozzi, V

2015-06-01

To characterize Oenococcus oeni strains isolated from North-Apulian wines where malic acid degradation is usually achieved by spontaneous fermentations, and to determine the influence of bacterial inoculation time on the malolactic performances in 'Nero di Troia' wine using a complete autochthonous microbial regime. Oenococcus oeni strains from wines produced with the autochthonous (Apulia Region, southern Italy) grape variety 'Uva di Troia' were isolated, selected and characterized. Multilocus sequence typing and variable number tandem repeat analysis were used to investigate intraspecific diversity. Oenococcus oeni strains were tested in co-inoculation and in sequential inoculation, with two autochthonous yeast strains previously isolated from 'Nero di Troia' wine. After a preliminary screening using co-inoculation regime, the O. oeni strains were grouped in reason of the different behaviour in malic acid performances. Results suggested that the efficient degradation of malic acid in co-inoculation is a strain-dependent characteristic. Autochthonous yeast/bacterium combinations were identified as starter culture, and used in a co-inoculation approach, for vinification of regional wines. The 'microbial terroir' of typical fermented food and beverage production represents a dynamic sector of applied research in food microbiology. In this work, we propose the use of autochthonous bacteria and yeast for wine production from an indigenous grape variety. © 2015 The Society for Applied Microbiology.

Quality Characteristics and Antioxidant Activity of Yogurt Supplemented with Aronia (Aronia melanocarpa) Juice.

PubMed

Nguyen, Linh; Hwang, Eun-Sun

2016-12-01

We investigated the quality characteristics and antioxidant activities of yogurt supplemented with 1%, 2%, and 3% aronia juice and fermented for 24 h at 37°C. The total acidity increased with increasing levels of aronia juice and incubation time. Lightness and yellowness of the yogurt decreased, but redness increased, with increasing aronia juice content and incubation time. The number of lactic acid bacteria (LAB) increased with increased incubation time, and yogurt containing 2% and 3% aronia juice showed higher LAB counts than 1% aroinia juice-supplemented yogurt. The total polyphenol and flavonoid contents increased proportionally with increasing levels of aronia juice. Antioxidant activity of aronia-containing yogurt was significantly higher than that of the control and increased proportionally with aronia juice concentration. Yogurt with 2% aronia juice had the best taste ( P <0.05). Aronia juice may be a useful additive for improving the taste and antioxidant potential of yogurt.

Identification and characterization of filamentous fungi isolated from fermentation starters for Hong Qu glutinous rice wine brewing.

PubMed

Lv, Xu-Cong; Huang, Zhi-Qing; Zhang, Wen; Rao, Ping-Fan; Ni, Li

2012-01-01

Hong Qu glutinous rice wine is one of the most popular traditional rice wines in China. Traditionally, this wine is brewed from glutinous rice with the addition of wine fermentation starters (Hong Qu (also called red yeast rice) and White Qu). The objective of this study was to investigate the variability of filamentous fungi associated with traditional fermentation starters through a traditional culture-dependent method and a molecular identification approach. In this study, forty-three filamentous fungi were separated by traditional culture-dependent means (macro- and microscopic characteristics) from 10 fermentation starters and classified into 16 different species based on morphological examination and the internal transcribed spacer (ITS) sequences analysis. It was observed that the genus Aspergillus had the highest number (14 isolates) of isolates followed by Rhizopus (11 isolates), Monascus (5 isolates) and Penicillium (4 isolates). The species R. oryzae, A. niger, A. flavus and M. purpureus were frequently found in wine starter samples, among which R. oryzae was the most frequent species. The enzyme-producing properties (glucoamylase, α-amylase and protease) of all fungal isolates from different starters were also evaluated. A. flavus, R. oryzae and M. purpureus were found to be better glucoamylase producers. A. flavus, R. oryzae and A.oryzae exhibited higher activity of α-amylase. A. flavus and A. oryzae had higher protease activity. However, some fungal isolates of the same species exhibited a significant variability in the production levels for all determined enzyme activity. This study is the first to identify filamentous fungi associated with the starter of Hong Qu glutinous rice wine using both traditional and molecular methods. The results enrich our knowledge of liquor-related micro-organisms, and can be used to promote the development of the traditional fermentation technology.

Antibiotic Resistances of Yogurt Starter Cultures Streptococcus thermophilus and Lactobacillus bulgaricus

PubMed Central

Sozzi, Tommaso; Smiley, Martin B.

1980-01-01

Twenty-nine strains of Lactobacillus bulgaricus and 15 strains of Streptococcus thermophilus were tested for resistance to 35 antimicrobial agents by using commercially available sensitivity disks. Approximately 35% of the isolates had uncharacteristic resistance patterns. PMID:16345654

Dynamics of fecal microbiota in hospitalized elderly fed probiotic LKM512 yogurt.

PubMed

Matsumoto, Mitsuharu; Sakamoto, Mitsuo; Benno, Yoshimi

2009-08-01

The comprehensive dynamics of intestinal microbiota including uncultured bacteria in response to probiotic consumption have not been well studied. The aims of this study were twofold: firstly to analyze the impact on intestinal microbiota of yogurt fermented by Bifidobacterium animalis subsp. lactis LKM512, Lactobacillus delbrueckii subsp. bulgaricus LKM1759, and Streptococcus thermophilus LKM1742 (LKM512 yogurt) and placebo fermented by these lactic acid bacterial strains without LKM512; and secondly to investigate the changes in intestinal microbiota that influence the concentration of PA, one of the beneficial metabolites produced by bacteria in the intestine. The LKM512 yogurt/placebo trial was performed in six hospitalized elderly patients (three men and three women with an average age of 80.3 years) and lasted seven weeks with the following schedule: pre-consumption for one week, LKM512 yogurt consumption for two weeks, washout period for two weeks, and placebo consumption for two weeks. The amount of ingested LKM512 yogurt or placebo was 100 g/day/individual. Fecal samples were analyzed using T-RFLP and real-time PCR. The T-RFLP patterns in five of the six volunteers were changed in a similar fashion by LKM512 yogurt consumption, although these patterns were individually changed following consumption of placebo. It was confirmed that B. animalis subsp. lactis was increased dramatically and Lactobacillus spp. tended to be decreased by LKM512 yogurt consumption. Some indigenous uncultured bacteria were increased and some decreased by LKM512 yogurt/placebo consumption. The similar changes in the intestinal microbiota of the elderly caused by consumption of the LKM512 yogurt were found to be influenced by the LKM512 strain itself, and not by the lactic acid bacteria in the yogurt. Moreover, this study suggests that the increase in intestinal PA concentrations caused by LKM512 yogurt consumption is probably dependent on the LKM512 strain colonizing the intestine.

Quality Characteristics and Antioxidant Activity of Yogurt Supplemented with Aronia (Aronia melanocarpa) Juice

PubMed Central

Nguyen, Linh; Hwang, Eun-Sun

2016-01-01

We investigated the quality characteristics and antioxidant activities of yogurt supplemented with 1%, 2%, and 3% aronia juice and fermented for 24 h at 37°C. The total acidity increased with increasing levels of aronia juice and incubation time. Lightness and yellowness of the yogurt decreased, but redness increased, with increasing aronia juice content and incubation time. The number of lactic acid bacteria (LAB) increased with increased incubation time, and yogurt containing 2% and 3% aronia juice showed higher LAB counts than 1% aroinia juice-supplemented yogurt. The total polyphenol and flavonoid contents increased proportionally with increasing levels of aronia juice. Antioxidant activity of aronia-containing yogurt was significantly higher than that of the control and increased proportionally with aronia juice concentration. Yogurt with 2% aronia juice had the best taste (P<0.05). Aronia juice may be a useful additive for improving the taste and antioxidant potential of yogurt. PMID:28078255

Enhanced Bioaccessibility of Curcuminoids in Buttermilk Yogurt in Comparison to Curcuminoids in Aqueous Dispersions.

PubMed

Fu, Shishan; Augustin, Mary Ann; Sanguansri, Luz; Shen, Zhiping; Ng, Ken; Ajlouni, Said

2016-03-01

Curcuminoids have low bioavailability due to low aqueous solubility. We compared the bioaccessibility of curcuminoids delivered in buttermilk yogurt to that of curcuminoid powder in an aqueous dispersion. Buttermilk containing added curcuminoids (300 mg/100 g, 0.3% w/w) was used for yogurt manufacture. We measured percentage of curcuminoids remaining in yogurts after manufacture and after exposure to simulated gastrointestinal fluids, and the in vitro bioaccessibility of the curcuminoids. Curcuminoids were stable during yogurt manufacture. At the end of in vitro digestion, approximately 11% of the curcuminoids delivered in yogurt was degraded compared to <1% for curcuminoids in an aqueous dispersion. However, curcuminoids delivered in yogurt was 15-fold more bioaccessible than curcuminoids in aqueous dispersion. The small change in yogurt properties (decrease in total lactic acid bacteria counts of <1 log and increased viscosity) on addition of curcuminoids has to be balanced against the benefits of increased bioaccessibility of curcuminoids when delivered in yogurts. © 2016 Institute of Food Technologists®

Role of milk protein-based products in some quality attributes of goat milk yogurt.

PubMed

Gursel, A; Gursoy, A; Anli, E A K; Budak, S O; Aydemir, S; Durlu-Ozkaya, F

2016-04-01

Goat milk yogurts were manufactured with the fortification of 2% (wt/vol) skim goat milk powder (SGMP), sodium caseinate (NaCn), whey protein concentrate (WPC), whey protein isolate (WPI), or yogurt texture improver (YTI). Yogurts were characterized based on compositional, microbiological, and textural properties; volatile flavor components (with gas chromatography); and sensory analyses during storage (21d at 5 °C). Compared with goat milk yogurt made by using SGMP, the other goat milk yogurt variants had higher protein content and lower acidity values. Goat milk yogurts with NaCn and WPC, in particular, had better physical characteristics. Using WPI caused the hardest structure in yogurt, leading to higher syneresis values. Acetaldehyde and ethanol formation increased with the incorporation of WPI, WPC, or YTI to yogurt milk. The tyrosine value especially was higher in the samples with NaCn and YTI than in the samples with WPC and WPI. Counts of Streptococcus thermophilus were higher than the counts of Lactobacillus delbrueckii ssp. bulgaricus, possibly due to a stimulatory effect of milk protein-based ingredients other than SGMP on the growth of S. thermophilus. Yogurt with NaCn was the best accepted among the yogurts. For the parameters used, milk protein-based products such as NaCn or WPC have promising features as suitable ingredients for goat milk yogurt manufacture. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The cocoa bean fermentation process: from ecosystem analysis to starter culture development.

PubMed

De Vuyst, L; Weckx, S

2016-07-01

Cocoa bean fermentation is still a spontaneous curing process to facilitate drying of nongerminating cocoa beans by pulp removal as well as to stimulate colour and flavour development of fermented dry cocoa beans. As it is carried out on farm, cocoa bean fermentation is subjected to various agricultural and operational practices and hence fermented dry cocoa beans of variable quality are obtained. Spontaneous cocoa bean fermentations carried out with care for approximate four days are characterized by a succession of particular microbial activities of three groups of micro-organisms, namely yeasts, lactic acid bacteria (LAB) and acetic acid bacteria (AAB), which results in well-fermented fully brown cocoa beans. This has been shown through a plethora of studies, often using a multiphasic experimental approach. Selected strains of several of the prevailing microbial species have been tested in appropriate cocoa pulp simulation media to unravel their functional roles and interactions as well as in small plastic vessels containing fresh cocoa pulp-bean mass to evaluate their capacity to dominate the cocoa bean fermentation process. Various starter cultures have been proposed for successful fermentation, encompassing both cocoa-derived and cocoa nonspecific strains of (hybrid) yeasts, LAB and AAB, some of which have been implemented on farms successfully. © 2016 The Society for Applied Microbiology.

Physicochemical Characteristics and Antioxidant Capacity in Yogurt Fortified with Red Ginseng Extract.

PubMed

Jung, Jieun; Paik, Hyun-Dong; Yoon, Hyun Joo; Jang, Hye Ji; Jeewanthi, Renda Kankanamge Chaturika; Jee, Hee-Sook; Li, Xiang; Lee, Na-Kyoung; Lee, Si-Kyung

2016-01-01

The objective of this study was to investigate characteristics and functionality of yogurt applied red ginseng extract. Yogurts added with red ginseng extract (0.5, 1, 1.5, and 2%) were produced using Lactobacillus acidophilus and Streptococcus thermophilus and stored at refrigerated temperature. During fermentation, pH was decreased whereas titratable aicidity and viable cell counts of L. acidophilus and S. thermophilus were increased. The composition of yogurt samples was measured on day 1, an increase of red ginseng extract content in yogurt resulted in an increase in lactose, protein, total solids, and ash content, whereas fat and moisture content decreased. The pH value and cell counts of L. acidophilus and S. thermophilus were declined, however titratable acidity was increased during storage period. The antioxidant capacity was measured as diverse methods. During refrigerated storage time, the value of antioxidant effect was decreased, however, yogurt fortified with red ginseng extract had higher capacity than plain yogurt. The antioxidant effect was improved in proportion to concentration of red ginseng extract. These data suggests that red ginseng extract could affect to reduce fermentation time of yogurt and enhance antioxidant capacity.

Study on fast discrimination of varieties of yogurt using Vis/NIR-spectroscopy

NASA Astrophysics Data System (ADS)

He, Yong; Feng, Shuijuan; Deng, Xunfei; Li, Xiaoli

2006-09-01

A new approach for discrimination of varieties of yogurt by means of VisINTR-spectroscopy was present in this paper. Firstly, through the principal component analysis (PCA) of spectroscopy curves of 5 typical kinds of yogurt, the clustering of yogurt varieties was processed. The analysis results showed that the cumulate reliabilities of PC1 and PC2 (the first two principle components) were more than 98.956%, and the cumulate reliabilities from PC1 to PC7 (the first seven principle components) was 99.97%. Secondly, a discrimination model of Artificial Neural Network (ANN-BP) was set up. The first seven principles components of the samples were applied as ANN-BP inputs, and the value of type of yogurt were applied as outputs, then the three-layer ANN-BP model was build. In this model, every variety yogurt includes 27 samples, the total number of sample is 135, and the rest 25 samples were used as prediction set. The results showed the distinguishing rate of the five yogurt varieties was 100%. It presented that this model was reliable and practicable. So a new approach for the rapid and lossless discrimination of varieties of yogurt was put forward.

Physicochemical Characteristics and Antioxidant Capacity in Yogurt Fortified with Red Ginseng Extract

PubMed Central

Jung, Jieun; Paik, Hyun-Dong; Yoon, Hyun Joo; Jang, Hye Ji; Jeewanthi, Renda Kankanamge Chaturika; Jee, Hee-Sook; Lee, Na-Kyoung

2016-01-01

The objective of this study was to investigate characteristics and functionality of yogurt applied red ginseng extract. Yogurts added with red ginseng extract (0.5, 1, 1.5, and 2%) were produced using Lactobacillus acidophilus and Streptococcus thermophilus and stored at refrigerated temperature. During fermentation, pH was decreased whereas titratable aicidity and viable cell counts of L. acidophilus and S. thermophilus were increased. The composition of yogurt samples was measured on day 1, an increase of red ginseng extract content in yogurt resulted in an increase in lactose, protein, total solids, and ash content, whereas fat and moisture content decreased. The pH value and cell counts of L. acidophilus and S. thermophilus were declined, however titratable acidity was increased during storage period. The antioxidant capacity was measured as diverse methods. During refrigerated storage time, the value of antioxidant effect was decreased, however, yogurt fortified with red ginseng extract had higher capacity than plain yogurt. The antioxidant effect was improved in proportion to concentration of red ginseng extract. These data suggests that red ginseng extract could affect to reduce fermentation time of yogurt and enhance antioxidant capacity. PMID:27433113

In-vitro microbial production of conjugated linoleic acid by probiotic L. plantarum strains: Utilization as a functional starter culture in sucuk fermentation.

PubMed

Özer, Cem O; Kılıç, Birol; Kılıç, Gülden Başyiğit

2016-04-01

Twenty-three probiotic Lactobacillus plantarum strains were screened in-vitro to determine their ability to produce conjugated linoleic acid (CLA). L. plantarum AA1-2 and L. plantarum AB20-961 were identified as potential strains for CLA production. Optimum conditions for these strains to produce high levels of CLA were determined by evaluating the amount of added hydrolyzed sunflower oil (HSO) and initial pH levels in a nutrient medium. The highest CLA production was obtained in medium with pH6.0 and 2% HSO (P<0.05). Those strains were then used as starter culture in sucuk fermentation. Five sucuk treatments included a control (no starter culture), two sucuk groups with L. plantarum AA1-2 at the initial pH of 5.8 or 6.0 and two sucuk groups with L. plantarum AB20-961 at the initial pH of 5.8 or 6.0. Results indicate that L. plantarum AB20-961 produced higher amount of CLA in sucuk at initial pH of 5.8 and 6.0 levels during first 24h of fermentation compared with other groups. CLA isomer concentration decreased in all sucuk groups during the rest of the fermentation period (P<0.05) and remained quite stable during the storage. This study demonstrated that probiotic L. plantarum AB20-961 can be used in sucuk manufacturing without posing any quality problems. Copyright © 2015 Elsevier Ltd. All rights reserved.

The yogurt amino acid profile's variation during the shelf-life.

PubMed

Germani, A; Luneia, R; Nigro, F; Vitiello, V; Donini, L M; del Balzo, V

2014-01-01

To analyze the yogurt amino acid profile starting from marketing through the whole shelf-life. The evaluation of the proteolytic activity of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus, allows to deduce their vitality during the shelf-life period and within 45 days. Three types of full fats yogurts have been analyzed (a) natural white (b) sweet white and (c) whole fruit - in two stages: t0 (first day of shelf-life) and t1 (end of shelf-life). The proteins have been analyzed by the Kjeldahl method and the amino acid profile by HPLC. In natural yogurt a significant increase of the amount of free amino acids has been observed during the period of shelf-life (97%). In the sweetened full fats and fruit yogurt, instead, there is a lower increase of respectively 33% and 39% In whole milk natural yogurt, based on our data, the proteolytic activity seems to persist during the entire period of the shelf-life and this can be considered an index of bacterial survival, especially of Lactobacillus delbrueckii subsp. bulgaricus during the marketing process.

Effect of Probiotic Yogurt and Xylitol-Containing Chewing Gums on Salivary S Mutans Count.

PubMed

Ghasemi, Elnaz; Mazaheri, Romina; Tahmourespour, Arezoo

In addition to improving gastrointestinal health and intestinal microflora, probiotic bacteria have been recently suggested to decrease cariogenic agents in the oral cavity. The aim of this study was to investigate the effects of probiotic yogurt and xylitol-containing chewing gums on reducing salivary Streptococcus mutans levels. This randomized clinical trial recruited 50 female students with over 10 5 colony forming units S. mutans per milliliter of their saliva. The participants were randomly allocated to two equal groups to receive either probiotic yogurt containing Lactobacillus acidophilus ATCC 4356 andBifidobacteriumbifidum ATCC 29521 (200 g daily) or xylitol-containing chewing gums (two gums three times daily after each meal; total xylitol content: 5.58 g daily) for three weeks. At baseline and one day, two weeks, and four weeks after the interventions, saliva samples were cultured on mitis-salivarius-bacitracin agar and salivary S. mutans counts were determined. Data were analyzed with independent t-tests, analysis of variance, and Fisher's least significant difference test. In both groups, S. mutans counts on the first day, second week, and fourth weeks after the intervention were significantly lower than baseline values (P < 0.05). The greatest level of reduction in both groups was observed in the second week after the intervention. Moreover, although the reduction was greater in probiotic yogurt consumers, the difference between the two groups was not statistically significant. Probiotic yogurt and xylitol-containing chewing gums seem to be as effective in reduction of salivary S. mutans levels. Their constant long-term consumption is thus recommended to prevent caries.

Impact of starter culture, ingredients, and flour type on sourdough bread volatiles as monitored by selected ion flow tube-mass spectrometry.

PubMed

Van Kerrebroeck, Simon; Comasio, Andrea; Harth, Henning; De Vuyst, Luc

2018-04-01

This study deals with the detection of volatile compounds originating from the crumb of breads made with sourdoughs obtained through starter culture-initiated fermentations, which differed in flour type (wheat and teff), ingredients (citrate and malate), fermentation time (24h or 72h), and starter culture strains (homo- and heterofermentative lactic acid bacteria species and acetic acid bacteria species) applied. Therefore, selected ion flow tube-mass spectrometry (SIFT-MS) was used. SIFT-MS is an easy-to-use and promising technique in the field of food and flavor analysis. Volatile compounds of crumb samples from the breads with sourdough were measured and compared with those of reference bread crumb samples. In general, sourdough addition had a positive effect on the concentrations of the volatile compounds measured by SIFT-MS. Furthermore, a trend toward higher concentrations of several volatiles was seen upon the addition of sourdoughs that were fermented up to 72h, compared to the addition of sourdoughs that were fermented for a shorter time. Ethanol was the major volatile compound identified tentatively, next to alcohols, aldehydes, esters, terpenes, and heterocyclic compounds. Also acetoin/ethyl acetate could be identified, but these compounds could not be distinguished. Higher alcohols showed an increase upon the use of sourdough fermented for a long time. High concentrations of acetic acid were found in breads made with Gluconobacter oxydans IMDO A845-initiated sourdough, indicating its potential for sourdough production. Breads made with teff sourdoughs were distinct from wheat-based sourdough breads as to their volatile compound profiles. Copyright © 2018 Elsevier Ltd. All rights reserved.

Measures and metrics of sustainable diets with a focus on milk, yogurt, and dairy products

PubMed Central

Drewnowski, Adam

2018-01-01

The 4 domains of sustainable diets are nutrition, economics, society, and the environment. To be sustainable, foods and food patterns need to be nutrient-rich, affordable, culturally acceptable, and sparing of natural resources and the environment. Each sustainability domain has its own measures and metrics. Nutrient density of foods has been assessed through nutrient profiling models, such as the Nutrient-Rich Foods family of scores. The Food Affordability Index, applied to different food groups, has measured both calories and nutrients per penny (kcal/$). Cultural acceptance measures have been based on relative food consumption frequencies across population groups. Environmental impact of individual foods and composite food patterns has been measured in terms of land, water, and energy use. Greenhouse gas emissions assess the carbon footprint of agricultural food production, processing, and retail. Based on multiple sustainability metrics, milk, yogurt, and other dairy products can be described as nutrient-rich, affordable, acceptable, and appealing. The environmental impact of dairy farming needs to be weighed against the high nutrient density of milk, yogurt, and cheese as compared with some plant-based alternatives. PMID:29206982

Yogurt for treating acute gastroenteritis in children: Systematic review and meta-analysis.

PubMed

Patro-Gołąb, Bernadeta; Shamir, Raanan; Szajewska, Hania

2015-10-01

In May 2014, the updated guidelines for the management of acute gastroenteritis (AGE) were published. The use of yogurt in the nutritional management of AGE was not addressed, although it is frequently used in many countries for this purpose. We aimed to systematically evaluate the efficacy of yogurt consumption for the management of AGE in children. In this systematic review, a number of databases, including MEDLINE, EMBASE, and the Cochrane Library, with no language restrictions, were searched up to July 2014 for randomized controlled trials (RCTs) evaluating the effect of yogurt consumption in children with AGE. The risk of bias was assessed using the Cochrane risk of bias tool. Four RCTs (n = 448) that were generally low in methodological quality, all performed in hospital setting, were included. Compared with placebo/no intervention, yogurt consumption had no significant effect on stool volume. The data on the effect of yogurt consumption on the duration of diarrhea and stool frequency were not consistent. The chance of treatment success (or failure) was similar in both groups. Compared with placebo, the duration of hospitalization was shorter in children who received yogurt, but the difference was of a borderline significance. Total weight gain increased for those treated with yogurt. The consumption of yogurt had a positive effect on weight gain, but no consistent effect on AGE outcomes in hospitalized children. Given the limited data and the methodological limitations of the included trials, the evidence should be viewed with caution. The effect of yogurt consumption in the ambulatory setting is unknown. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

JPRS Report, Science & Technology, Europe

DTIC Science & Technology

1992-03-27

bio-engineering company, among other things, cultivates starter cultures for the production of cheese and yogurt . The customers are dairy farmers in...produces the alcohol with the help of traditional fermentation methods. This means they use ordinary baker’s yeast which fer- ments part of the sugar in...the waste liquid into ethanol. The baker’s yeast is unable to ferment the remaining sugars in the liquid, such as xylose, for example, into alcohol

Some low homogenization pressures improve certain probiotic characteristics of yogurt culture bacteria and Lactobacillus acidophilus LA-K.

PubMed

Muramalla, T; Aryana, K J

2011-08-01

Lactobacillus delbrueckii ssp. bulgaricus, Streptococcus salivarius ssp. thermophilus, and Lactobacillus acidophilus are dairy cultures widely used in the manufacture of cultured dairy products. Commonly used homogenization pressures in the dairy industry are 13.80 MPa or less. It is not known whether low homogenization pressures can stimulate bacteria to improve their probiotic characteristics. Objectives were to determine the effect of homogenization at 0, 3.45, 6.90, 10.34, and 13.80 MPa on acid tolerance, bile tolerance, protease activity, and growth of L. delbrueckii ssp. bulgaricus LB-12, S. salivarius ssp. thermophilus ST-M5, and L. acidophilus LA-K. The cultures were individually inoculated in cool autoclaved skim milk (4°C) and homogenized for 5 continuous passes. Growth and bile tolerance of samples were determined hourly for 10h of incubation. Acid tolerance was determined every 20 min for 120 min of incubation. Protease activity was determined at 0, 12, and 24h of incubation. All homogenization pressures studied improved acid tolerance of L. delbrueckii ssp. bulgaricus LB-12 but had no beneficial effect on protease activity and had negative effects on growth and bile tolerance. A pressure of 6.90 MPa improved acid tolerance, bile tolerance, and protease activity of S. salivarius ssp. thermophilus ST-M5, but none of the homogenization pressures studied had an effect on its growth. Homogenization pressures of 13.80 and 6.90 MPa improved acid tolerance and bile tolerance, respectively, of L. acidophilus LA-K but had no effect on protease activity and its growth. Some low homogenization pressures positively influenced some characteristics of yogurt culture bacteria and L. acidophilus LA-K. Culture pretreatment with some low homogenization pressures can be recommended for improvement of certain probiotic characteristics. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Anti-obesity effect of kimchi fermented with Weissella koreensis OK1-6 as starter in high-fat diet-induced obese C57BL/6J mice.

PubMed

Park, J-A; Tirupathi Pichiah, P B; Yu, J-J; Oh, S-H; Daily, J W; Cha, Y-S

2012-12-01

In this study, we investigated the anti-obesity effects of kimchi (Korean traditional fermented vegetable) fermented either without starter culture or with a specific starter culture, Weissella koreensis OK1-6. C57BL/6J mice were divided into four groups (n = 7); normal diet, HF (high-fat diet), HF-KC (high-fat diet containing 3% kimchi manufactured without starter) and HF-KCO (high-fat diet containing 3% kimchi manufactured with the starter culture W. koreensis OK1-6). After 12 weeks of dietary intervention, the mice were killed, and serum and tissue samples were examined. Serum and hepatic lipid profile, insulin, leptin concentration and expression level of lipid anabolic genes like peroxisome proliferator-activated receptor γ, stearoyl-CoA desaturase-1, liver X receptor α and SREBP2 were significantly decreased (<0.05) along with body and epididymal fat pad weight in the HF-KCO group compared with the HF-KC and HF group. These results suggested that kimchi fermented with the starter W. koreensis OK1-6 has anti-obesity effects in HF-induced obese mice. These results may contribute to nutraceutical and food industries in developing functional food and probiotics based therapies for the treatment and prevention of obesity. © 2012 The Society for Applied Microbiology.

The future of yogurt: scientific and regulatory needs1234

PubMed Central

German, J Bruce

2014-01-01

Lactation biology, microbial selection, and human diversity are central themes that could guide investment in scientific research, industrial innovation, and regulatory policy oversight to propel yogurt into the central role for health-promoting food products. The ability of yogurt to provide the nourishing properties of milk together with the live microorganisms from fermentation provides a unique combination of food assets. Academic research must now define the various targets on which these biological assets act to improve health and develop the metrics that can quantitatively document their benefits. The food industry must reconcile that yogurt and its microorganisms cannot be expected to provide measurable benefits for all consumers, at all doses, and at all times. A supportive regulatory oversight must demand safety and yet encourage innovations that support a value proposition for yogurt in health. Health valuation in the marketplace will be driven by parallel innovations, including accurate assessment technologies, validated microbial ingredients, and health-aware consumers. PMID:24695899

The effect of microbial starter composition on cassava chips fermentation for the production of fermented cassava flour

NASA Astrophysics Data System (ADS)

Kresnowati, M. T. A. P.; Listianingrum, Zaenudin, Ahmad; Trihatmoko, Kharisrama

2015-12-01

The processing of cassava into fermented cassava flour (fercaf) or the widely known as modified cassava flour (mocaf) presents an alternative solution to improve the competitiveness of local foods and to support national food security. However, the mass production of fercaf is being limited by several problems, among which is the availability of starter cultures. This paper presents the mapping of the effect of microbial starter compositions on the nutritional content of fercaf in order to obtain the suitable nutritional composition. Based on their enzymatic activities, the combination of Lactobacillus plantarum, Bacillus subtilis, and Aspergillus oryzae were tested during the study. In addition, commercial starter was also tested. During the fermentation, the dynamics in microbial population were measured as well as changes in cyanogenic glucoside content. The microbial starter composition was observed to affect the dynamics in microbial populationcynaogenic glucoside content of the produced fercaf. In general, steady state microbial population was reached within 12 hours of fermentation. Cyanogenic glucoside was observed to decrease along the fermentation.

Oxidative changes in lipids, proteins, and antioxidants in yogurt during the shelf life.

PubMed

Citta, Anna; Folda, Alessandra; Scalcon, Valeria; Scutari, Guido; Bindoli, Alberto; Bellamio, Marco; Feller, Emiliano; Rigobello, Maria Pia

2017-11-01

Oxidation processes in milk and yogurt during the shelf life can result in an alteration of protein and lipid constituents. Therefore, the antioxidant properties of yogurt in standard conditions of preservation were evaluated. Total phenols, free radical scavenger activity, degree of lipid peroxidation, and protein oxidation were determined in plain and skim yogurts with or without fruit puree. After production, plain, skim, plain berries, and skim berries yogurts were compared during the shelf life up to 9 weeks. All types of yogurts revealed a basal antioxidant activity that was higher when a fruit puree was present but gradually decreased during the shelf life. However, after 5-8 weeks, antioxidant activity increased again. Both in plain and berries yogurts lipid peroxidation increased until the seventh week of shelf life and after decreased, whereas protein oxidation of all yogurts was similar either in the absence or presence of berries and increased during shelf life. During the shelf life, a different behavior between lipid and protein oxidation takes place and the presence of berries determines a protection only against lipid peroxidation.

Evaluation of bacterial communities belonging to natural whey starters for Grana Padano cheese by length heterogeneity-PCR.

PubMed

Lazzi, C; Rossetti, L; Zago, M; Neviani, E; Giraffa, G

2004-01-01

To detect bacteria present in controlled dairy ecosystems with defined composition by length-heterogeneity (LH)-PCR. LH-PCR allows to distinguish different organisms on the basis of natural variations in the length of 16S rRNA gene sequences. LH-PCR was applied to depict population structure of the lactic acid bacteria (LAB) species recoverable from Grana Padano cheese whey starters. Typical bacterial species present in the LAB community were evidenced and well discriminated. Small differences in species composition, e.g. the frequent finding of Streptococcus thermophilus and the constant presence of thermophilic lactobacilli (Lactobacillus helveticus, Lact. delbrueckii subsp. lactis/bulgaricus and Lact. fermentum) were reliably highlighted. Specificity of LH-PCR was confirmed by species-specific PCR from total DNA of the cultures. LH-PCR is a useful tool to monitor microbial composition and population dynamics in dairy starter cultures. When present, non-dominant bacterial species present in the whey starters, such as Strep. thermophilus, can easily be visualized and characterized without isolating and cultivating single strains. A similar approach can be applied to more complex dairy ecosystems such as milk or cheese curd. Community members and differences in population structure of controlled dairy ecosystems such as whey starters for hard cheeses can be evaluated and compared in a relative easy, fast, reliable and highly reproducible way.

Effects of Freeze-dried Mulberry on Antioxidant Activities and Fermented Characteristics of Yogurt during Refrigerated Storage.

PubMed

Sung, Jung-Min; Kim, Young-Boong; Kum, Jun-Seok; Choi, Yun-Sang; Seo, Dong-Ho; Choi, Hyun-Wook; Park, Jong-Dae

2015-01-01

This study investigated the effect of added freeze-dried mulberry fruit juice (FDMJ) (1, 3 and 5%) on the antioxidant activity and fermented characteristic of yogurt during refrigerated storage. A decrease in pH of yogurt and increase in acidity was observed during fermentation. The yogurts with FDMJ exhibited faster rate of pH reduction than control. Initial lactic acid bacteria count of yogurt was 6.49-6.94 Log CFU/g and increased above 9 Log CFU/g in control and 1% in FDMJ yogurt for 24 h. The total polyphenol and anthocyanin content of FDMJ yogurt was higher than that of control due to the presence of phytochemical contents in mulberry. Moreover, antioxidant activity such as DPPH and reducing power was highest 5% FDMJ yogurt. During cold storage, pH decreased or remained constant in all yogurts with values ranging from 4.08 to 4.78 units. In sensory evaluation, the score of 1% FDMJ yogurt was ranked higher when compared with other yogurts. It is proposed that mulberry fruit juice powder can be used to improve sensory evaluation and enhance functionality of yogurt.

Effects of Freeze-dried Mulberry on Antioxidant Activities and Fermented Characteristics of Yogurt during Refrigerated Storage

PubMed Central

2015-01-01

This study investigated the effect of added freeze-dried mulberry fruit juice (FDMJ) (1, 3 and 5%) on the antioxidant activity and fermented characteristic of yogurt during refrigerated storage. A decrease in pH of yogurt and increase in acidity was observed during fermentation. The yogurts with FDMJ exhibited faster rate of pH reduction than control. Initial lactic acid bacteria count of yogurt was 6.49-6.94 Log CFU/g and increased above 9 Log CFU/g in control and 1% in FDMJ yogurt for 24 h. The total polyphenol and anthocyanin content of FDMJ yogurt was higher than that of control due to the presence of phytochemical contents in mulberry. Moreover, antioxidant activity such as DPPH and reducing power was highest 5% FDMJ yogurt. During cold storage, pH decreased or remained constant in all yogurts with values ranging from 4.08 to 4.78 units. In sensory evaluation, the score of 1% FDMJ yogurt was ranked higher when compared with other yogurts. It is proposed that mulberry fruit juice powder can be used to improve sensory evaluation and enhance functionality of yogurt. PMID:26877641

Peptide profiling and the bioactivity character of yogurt in the simulated gastrointestinal digestion.

PubMed

Jin, Yan; Yu, Yang; Qi, Yanxia; Wang, Fangjun; Yan, Jiaze; Zou, Hanfa

2016-06-01

This study investigated the relationship between peptide profiles and the bioactivity character of yogurt in simulated gastrointestinal trials. A total of 250, 434 and 466 peptides were identified by LC-MS/MS analyses of yogurt, gastric digest and pancreatic digest. Forty peptides of yogurt survived in gastrointestinal digestion. κ-CN and β-CN contributed the diversity of peptides during the fermentation process and gastrointestinal digestion, respectively. The favorite of κ-CN by lactic acid bacteria complemented gut digestion by hydrolyzing κ-CN, the low abundance milk proteins. The potential bioactivities were evaluated by in vitro ACE and DPP-IV inhibition assays. The ACE inhibition rate of the pancreatic digests was ~4 - and ~2 - fold greater than that of yogurt and the gastric digests. The ACE inhibitory peptides generated during gastrointestinal digestion improved the ACE inhibitory activity of the gastric and pancreatic digests. The DPP-IV inhibition rate of the pancreatic digest was ~6 - and ~3 - fold greater than that of yogurt and the gastric digest. The numbers of potential DPP-IV inhibitory peptides were positively correlated to the DPP-IV inhibitory activity of the gastric and pancreatic digests. The present study describes the characters and bioactivities of peptides from yogurt in a simulated gastrointestinal digestion. The number of peptides identified from yogurt and gastrointestinal digests by LC-MS/MS increased in the simulated gastrointestinal trials. The in vitro ACE and DPP-IV inhibition bioactivities revealed that the bioactivity of yogurt was enhanced during gastrointestinal digestion. The correlation between peptides and bioactivity in vitro indicated that not only the peptides amount but also the proportion of peptides with high bioactivities contributed to increased bioactivity during gastrointestinal digestion. The study of peptides identified from yogurt and digests revealed that the number of released peptides was not determined

Developing a strawberry yogurt fortified with marine fish oil

USDA-ARS?s Scientific Manuscript database

Fortified dairy products appeal to a wide variety of consumers and have the potential to increase sales in the yogurt industry and contribute to boost the intake of omega-3 fatty acids. The objectives of this study were to develop a strawberry yogurt containing microencapsulated salmon oil (2% w/v) ...

Impact of eating probiotic yogurt on colonization by Candida species of the oral and vaginal mucosa in HIV-infected and HIV-uninfected women.

PubMed

Hu, Haihong; Merenstein, Daniel J; Wang, Cuiwei; Hamilton, Pilar R; Blackmon, Mandy L; Chen, Hui; Calderone, Richard A; Li, Dongmei

2013-10-01

Candidiasis in HIV/AIDS patients continues to be a public health problem. Antifungal therapies are not always effective and may result in complications, such as the development of drug-resistant strains of Candida species. This study evaluated the impact of probiotic consumption on Candida colonization of the oral and vaginal mucosa. A pilot study was conducted in 24 women (17 HIV-infected, 7 HIV-uninfected) from the Women's Interagency HIV Study. The women underwent a 60-day initiation period with no probiotic consumption, followed by two 15-day consumption periods, with a different probiotic yogurt (DanActive™ or YoPlus™ yogurt) during each interval. There was a 30-day washout period between the two yogurt consumption periods. Oral and vaginal culture swabs were collected on days 0, 60, 74, and 120. Candida was detected by inoculating each swab in both Sabouraud's dextrose agar with or without chloramphenicol and CHROMagar. Less fungal colonization among women was observed when the women consumed probiotic yogurts (54 % of the women had vaginal fungal colonization during the non-probiotic yogurt consumption period, 29 % during the DanActive™ period, and 38 % during YoPlus™ yogurt consumption period), and HIV-infected women had significantly lower vaginal fungal colonization after they consumed DanActive™ yogurt compared to the non-intervention periods (54 vs 29 %, p = 0.03). These data are promising, but as expected in a small pilot study, there were some significant changes but also some areas where colonization was not changed. This type of conflicting data is supportive of the need for a larger trial to further elucidate the role of probiotic yogurts in fungal growth in HIV-infected women.

Impact of Eating Probiotic Yogurt on Colonization by Candida Species of the Oral and Vaginal Mucosa in HIV-Infected and HIV-Uninfected Women

PubMed Central

Hu, Haihong; Wang, Cuiwei; Hamilton, Pilar R.; Blackmon, Mandy L.; Chen, Hui; Calderone, Richard A.; Li, Dongmei

2014-01-01

Background Candidiasis in HIV/AIDS patients continues to be a public health problem. Antifungal therapies are not always effective and may result in complications, such as the development of drug-resistant strains of Candida species. Objectives This study evaluated the impact of probiotic consumption on Candida colonization of the oral and vaginal mucosa. Patients/Methods A pilot study was conducted in 24 women (17 HIV-infected, 7 HIV-uninfected) from the Women's Interagency HIV Study. The women underwent a 60-day initiation period with no probiotic consumption, followed by two 15-day consumption periods, with a different probiotic yogurt (DanActive™ or YoPlus™ yogurt) during each interval. There was a 30-day washout period between the two yogurt consumption periods. Oral and vaginal culture swabs were collected on days 0, 60, 74, and 120. Candida was detected by inoculating each swab in both Sabouraud's dextrose agar with or without chloramphenicol and CHROMagar. Results Less fungal colonization among women was observed when the women consumed probiotic yogurts (54 % of the women had vaginal fungal colonization during the non-probiotic yogurt consumption period, 29 % during the DanActive™ period, and 38 % during YoPlus™ yogurt consumption period), and HIV-infected women had significantly lower vaginal fungal colonization after they consumed DanActive™ yogurt compared to the nonintervention periods (54 vs 29 %, p = 0.03). Conclusions These data are promising, but as expected in a small pilot study, there were some significant changes but also some areas where colonization was not changed. This type of conflicting data is supportive of the need for a larger trial to further elucidate the role of probiotic yogurts in fungal growth in HIV-infected women. PMID:23925786

Impact of yogurt on appetite control, energy balance, and body composition.

PubMed

Tremblay, Angelo; Doyon, Caroline; Sanchez, Marina

2015-08-01

Recent data support the idea that regular yogurt consumption promotes body weight stability. The simplest explanation is that regular consumption of healthful foods such as yogurt results in decreased intake of less healthful foods containing high amounts of fat and/or sugar. There is also evidence to suggest that the high calcium and protein contents of yogurt and other dairy foods influence appetite and energy intake. The existence of a calcium-specific appetite control mechanism has been proposed. Milk proteins differ in terms of absorption rate and post-absorptive responses, which can influence their satiating properties. Studies in humans have shown that consumption of milk and yogurt increases the circulating concentration of the anorectic peptides glucagon-like peptide (GLP)-1 and peptide YY (PYY). The food matrix can also affect appetite and satiety. Yogurt is a fermented milk that contains bacteria that enrich the microbiota of the host. It appears that lean vs obese humans differ in the composition of their gut microbiota. The available relevant literature suggests that yogurt is a food that facilitates the regulation of energy balance. © The Author(s) 2015. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Physicochemical and Microbiological Properties of Yogurt-cheese Manufactured with Ultrafiltrated Cow's Milk and Soy Milk Blends

PubMed Central

Lee, Na-Kyoung; Mok, Bo Ram; Jeewanthi, Renda Kankanamge Chaturika; Yoon, Yoh Chang; Paik, Hyun-Dong

2015-01-01

The objective of this study was to develop yogurt-cheese using cow’s milk, ultrafiltrated cow’s milk, and soy milk. The addition of soy milk and ultrafiltrated milk increased the amount of protein in the yogurt-cheese. Yogurt-cheeses were made using cheese base using 10% and 20% soy milk with raw and ultrafiltrated cow’s milk, and stored at 4℃ during 2 wk. The yield of yogurt-cheeses made with added soy milk was decreased and the cutting point was delayed compared to yogurt-cheese made without soy milk. Yogurt-cheese made using ultrafiltrated cow’s milk showed the highest yield. However, yogurt-cheese made with added soy milk had higher protein content and titratable acidity than yogurt-cheese made using raw and ultrafiltrated cow’s milk. Fat and lactose contents in the yogurt-cheese made with added soy milk were lower. Yogurt-cheeses made with added soy milk contained several soy protein bands corresponding to the sizes of α2-, β-, and κ-casein band. Yogurt-cheese made with added soy milk had similar elasticity to yogurt-cheese made without soy milk but had lower cohesiveness. There was no significant difference in the number of lactic acid bacteria in the different cheeses, as all had over 8.0 Log CFU/g. Considering these data and the fact that proteins and fats of vegetable origin with high biological value were observed as well as unsaturated fats, yogurt-cheese made with added soy milk can be considered to be a functional food. PMID:26761829

Flavour profiles of dry sausages fermented by selected novel meat starter cultures.

PubMed

Erkkilä, S; Petäjä, E; Eerola, S; Lilleberg, L; Mattila-Sandholm, T; Suihko, M L

2001-06-01

Probiotic or bioprotective Lactobacillus rhamnosus strains GG, LC-705 and E-97800 as well as Pediococcus pentosaceus E-90390 and Lactobacillus plantarum E-98098 were studied for their ability to act as main fermenting organisms in the manufacturing process of dry sausages. In the preliminary tests, their abilities to produce lactic acid and biogenic amines, histamine or tyramine, were studied in MRS broth and analysed by high-performance liquid chromatography. The strains produced higher or equal amounts of lactic acid compared to control and were amine negative. During the actual fermentation process of dry sausages the numbers of inoculated bacteria increased from the level 6.5-7.0 log cfu/g to 8.0-9.0 log cfu/g. The most fast growing strains were P. pentosaceus E-90390 and the control while the growth of L. plantarum E-98098 and L. rhamnosus LC-705 were the slowest. The pH value of the sausages decreased from 5.6 to 4.9-5.0. The presence of these experimental strains as major organisms in the sausages after fermentation and ripening was confirmed on the bases of their genetic fingerprints. The flavour profiles of the experimental sausages produced by these probiotic or protective strains were similar with that produced by the commercial meat starter culture and commercial North European dry sausage recipe.

Quality evaluation of polypropylene packaged corn yogurt during storage

NASA Astrophysics Data System (ADS)

Aini, Nur; Prihananto, V.; Sustriawan, B.; Astuti, Y.; Maulina, M. R.

2018-01-01

Packaging is an important factor to control the process of quality decrease of any food product, including to determine the shelf life. The objective of this study was to determine changes quality of corn yogurt packaged using polypropylene. The method were using was package yogurt polypropylene, then it was stored in a refrigerator at 5, 10, or 15°C during 21 days. The yogurt was analysed every 7 days over a 21-day period. The results indicate that protein content decreased during storage, while the lactic acid bacteria, total acid, pH, viscosity, and total solids were increased. At the end of storage, the amount of lactic acid bacteria still fulfil the minimum requirements of a probiotic food, with a count of 6.407 log CFU/g. Overal scoring by panelist (scores ranged from 0 to 5) have a 4.78 at the beginning of storage. By the 21st day of storage, yogurt was packaging using transparent polypropylene having a score of 3.85, and that stored in opaque white packaging having a value of 3.95.

Effect of yogurt containing deep sea water on health-related serum parameters and intestinal microbiota in mice.

PubMed

Kang, Sun Moon; Jhoo, Jin Woo; Pak, Jae In; Kwon, Ill Kyoung; Lee, Sung Ki; Kim, Gur Yoo

2015-09-01

Deep sea water (DSW) has health benefits and is widely used as food supplement; however, its effect in fermented products has not been explored. Here, we investigated the effect of DSW-containing yogurt on health-related serum parameters and intestinal microbiota in mice. Animals were assigned to 3 feeding groups, which received water (control), normal yogurt (N-yogurt), or DSW-containing yogurt (DSW-yogurt) with a basal diet. Mice were killed at wk 4 or 8 of feeding and analyzed for serum parameters and microbial population in the small intestine. Both yogurt groups demonstrated increased populations of intestinal lactic acid bacteria compared with the control group. The activity of serum aspartate aminotransferase and alanine aminotransferase was markedly decreased in the DSW-yogurt and N-yogurt groups, and triglyceride level tended to be lower in the DSW-yogurt group compared with that in the control mice. Furthermore, the DSW-yogurt group showed a more significant decrease in the ratio of total cholesterol to high-density lipoprotein-cholesterol than did the N-yogurt group. These findings suggest that DSW supplementation of yogurt can increase its beneficial effects on lipid metabolism. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Intake of High-Fat Yogurt, but Not of Low-Fat Yogurt or Prebiotics, Is Related to Lower Risk of Depression in Women of the SUN Cohort Study.

PubMed

Perez-Cornago, Aurora; Sanchez-Villegas, Almudena; Bes-Rastrollo, Maira; Gea, Alfredo; Molero, Patricio; Lahortiga-Ramos, Francisca; Martínez-González, Miguel Angel

2016-09-01

Yogurt and prebiotic consumption has been linked to better health. However, to our knowledge, no longitudinal study has assessed the association of yogurt and prebiotic consumption with depression risk. We longitudinally evaluated the association of yogurt and prebiotic consumption with depression risk in a Mediterranean cohort. The SUN (Seguimiento Universidad de Navarra) Project is a dynamic, prospective cohort of Spanish university graduates. A total of 14,539 men and women (mean age: 37 y) initially free of depression were assessed during a median follow-up period of 9.3 y. Validated food-frequency questionnaires at baseline and after a 10-y follow-up were used to assess prebiotic (fructans and galacto-oligosaccharide) intake and yogurt consumption (<0.5, ≥0.5 to <3, ≥3 to <7, and ≥7 servings/wk). Participants were classified as incident cases of depression when they reported a new clinical diagnosis of depression by a physician (previously validated). Multivariable Cox proportional hazards models were used to calculate HRs and 95% CIs. We identified 727 incident cases of depression during follow-up. Whole-fat yogurt intake was associated with reduced depression risk: HR for the highest [≥7 servings/wk (1 serving = 125 g)] compared with the lowest (<0.5 servings/wk) consumption: 0.78 (95% CI: 0.63, 0.98; P-trend = 0.020). When stratified by sex, this association was significant only in women (HR: 0.66; 95% CI: 0.50, 0.87; P-trend = 0.004). Low-fat yogurt consumption was associated with a higher incidence of depression (HR: 1.32; 95% CI: 1.06, 1.65; P-trend = 0.001), although this association lost significance after the exclusion of early incident cases, suggesting possible reverse causation bias. Prebiotic consumption was not significantly associated with depression risk. Our study suggests that high consumption of whole-fat yogurt was related to a lower risk of depression in women of the SUN cohort. No association was observed for prebiotics. Further

Prevention by lactic acid bacteria of the oxidation of human LDL.

PubMed

Terahara, M; Kurama, S; Takemoto, N

2001-08-01

Ether extracts of lactic acid bacteria were analyzed for prevention of the oxidation of erythrocyte membrane and human low-density lipoprotein in vivo. Streptococcus thermophilus 1131 and Lactobacillus delbrueckii subsp. bulgaricus 2038, yogurt starters, were chosen as test-strains, and ether extracts of these cultures were used as samples. Both strain 1131 and strain 2038 produced radical scavengers and inhibited oxidation of erythrocyte membranes and low-density lipoproteins. The antioxidative activity of strain 2038 was higher than that of strain 1131.

Probiotic yogurt improves antioxidant status in type 2 diabetic patients.

PubMed

Ejtahed, Hanie S; Mohtadi-Nia, Javad; Homayouni-Rad, Aziz; Niafar, Mitra; Asghari-Jafarabadi, Mohammad; Mofid, Vahid

2012-05-01

Oxidative stress plays a major role in the pathogenesis and progression of diabetes. Among various functional foods with an antioxidant effect, probiotic foods have been reported to repress oxidative stress. The objective of this clinical trial was to assess the effects of probiotic and conventional yogurt on blood glucose and antioxidant status in type 2 diabetic patients. Sixty-four patients with type 2 diabetes mellitus, 30 to 60 y old, were assigned to two groups in this randomized, double-blind, controlled clinical trial. The patients in the intervention group consumed 300 g/d of probiotic yogurt containing Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 and those in the control group consumed 300 g/d of conventional yogurt for 6 wk. Fasting blood samples, 24-h dietary recalls, and anthropometric measurements were collected at the baseline and at the end of the trial. Probiotic yogurt significantly decreased fasting blood glucose (P < 0.01) and hemoglobin A1c (P < 0.05) and increased erythrocyte superoxide dismutase and glutathione peroxidase activities and total antioxidant status (P < 0.05) compared with the control group. In addition, the serum malondialdehyde concentration significantly decreased compared with the baseline value in both groups (P < 0.05). No significant changes from baseline were shown in insulin concentration and erythrocyte catalase activity within either group (P > 0.05). The consumption of probiotic yogurt improved fasting blood glucose and antioxidant status in type 2 diabetic patients. These results suggest that probiotic yogurt is a promising agent for diabetes management. Copyright © 2012 Elsevier Inc. All rights reserved.

Molecular discrimination of lactobacilli used as starter and probiotic cultures by amplified ribosomal DNA restriction analysis.

PubMed

Roy, D; Sirois, S; Vincent, D

2001-04-01

Lactic acid bacteria such as Lactobacillus helveticus, L. delbrueckii subsp. delbrueckii, L. delbrueckii subsp. lactis, L. delbrueckii subsp. bulgaricus, L. acidophilus, and L. casei related taxa which are widely used as starter or probiotic cultures can be identified by amplified ribosomal DNA restriction analysis (ARDRA). The genetic discrimination of the related species belonging to these groups was first obtained by PCR amplifications by using group-specific or species-specific 16S rDNA primers. The numerical analysis of the ARDRA patterns obtained by using CfoI, HinfI, Tru9I, and ScrFI was an efficient typing tool for identification of species of the L. acidophilus and L. casei complex. ARDRA by using CfoI was a reliable method for differentiation of L. delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis. Finally, strains ATCC 393 and ATCC 15820 exhibited unique ARDRA patterns with CfoI and Tru9I restriction enzymes as compared with the other strains of L. casei, L. paracasei, and L. rhamnosus.

Effects of Psychrotrophic Bacteria, Serratia liquefaciens and Acinetobacter genomospecies 10 on Yogurt Quality

PubMed Central

Shin, Yong Kook; Oh, Nam Su; Lee, Hyun Ah; Choi, Jong-Woo

2014-01-01

The aim of this study was to evaluate the effect of proteolytic (Serratia liquefaciens, match %: 99.39) or lipolytic (Acinetobacter genomospecies 10, match %: 99.90) psychrotrophic bacteria (bacterial counts, analysis of free fatty acids (FFA) and analysis of free amino acids) on the microbial and chemical properties (yogurt composition), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of yogurt during storage. Yogurts were prepared with raw milk preinoculated with each psychrotrophic bacteria. The total solid, fat, and protein content were not affected by preinoculation, but the pH of yogurt preinoculated with psychrotrophic bacteria was higher than in control. There was a dramatic increase in short chain free fatty acids among FFA in yogurt with Acinetobacter genomospecies 10. For 14 d of cold storage condition, SCFFA was 25.3 mg/kg to 34.4 mg/kg (1.36 times increased), MCFFA was 20.4 mg/kg to 25.7 mg/kg (1.26 times increased), and LCFFA was 240.2 mg/kg to 322.8 mg/kg (1.34 times increased). Serratia liquefaciens (match %: 99.39) in yogurt caused a greater accumulation of free amino acids (FAA), especially bitter peptides such as leucine, valine, arginine, and tyrosine, but SDS-PAGE showed that the inoculation of Serratia liquefaciens did not affect the degree of casein degradation during storage. Taken together, the excessive peptides and FFA in yogurt generated from psychrotrophic bacteria could develop off-flavors that degrade the quality of commercial yogurt products. PMID:26761293

Industrial yogurt manufacture: monitoring of fermentation process and improvement of final product quality.

PubMed

Soukoulis, C; Panagiotidis, P; Koureli, R; Tzia, C

2007-06-01

Lactic acid fermentation during the production of skim milk and whole fat set-style yogurt was continuously monitored by measuring pH. The modified Gompertz model was successfully applied to describe the pH decline and viscosity development during the fermentation process. The viscosity and incubation time data were also fitted to linear models against ln(pH). The investigation of the yogurt quality improvement practices included 2 different heat treatments (80 degrees C for 30 min and 95 degrees C for 10 min), 3 milk protein fortifying agents (skim milk powder, whey powder, and milk protein concentrate) added at 2.0%, and 4 hydrocolloids (kappa-carrageenan, xanthan, guar gum, and pectin) added at 0.01% to whole fat and skim yogurts. Heat treatment significantly affected viscosity and acetaldehyde development without influencing incubation time and acidity. The addition of whey powder shortened the incubation time but had a detrimental effect on consistency, firmness, and overall acceptance of yogurts. On the other hand, addition of skim milk powder improved the textural quality and decreased the vulnerability of yogurts to syneresis. Anionic stabilizers (kappa-carrageenan and pectin) had a poor effect on the texture and palatability of yogurts. However, neutral gums (xanthan and guar gum) improved texture and prevented the wheying-off defect. Skim milk yogurts exhibited longer incubation times and higher viscosities, whereas they were rated higher during sensory evaluation than whole fat yogurts.

[Clinical consequences of replacing milk with yogurt in persistent infantile diarrhea].

PubMed

Touhami, M; Boudraa, G; Mary, J Y; Soltana, R; Desjeux, J F

1992-02-01

Persistent diarrhea is an episode of diarrhea that begins acutely but lasts longer than expected for this usually self-limited disease. Treatment of this ill-defined syndrome is not well standardized but immediate intervention is required to minimize the risk of malnutrition with its various consequences. This randomized clinical trial was undertaken to evaluate the clinical efficacy of substituting yogurt for milk, as the only treatment. After a one to two-day observation period during which a standard milk diet was given, 78 children aged 3 to 36 months with confirmed persistent diarrhea of more than 15 days but less than one month duration and negative tests for fecal blood were fed either milk (infant formula) or yogurt (infant formula fermented with Lactobacillus bulgaricus and Streptococcus thermophilus). At inclusion both groups were comparable for age, nutritional status, diarrhea, and lactose hydrogen breath test results. Clinical treatment failure (weight loss greater than 5% in one day or persistent diarrhea after 5 days) was significantly less common in children fed yogurt (15 +/- 6%) than in children fed milk (45 +/- 8%). The beneficial effects of feeding yogurt were apparent within 48 hours in 67 +/- 8% of infants. In conclusion, these data confirm the clinical efficacy of substituting yogurt for milk in young children with persistent diarrhea. They also suggest that yogurt may be a good alternative for the initial treatment of persistent diarrhea.

Identification of yeasts and evaluation of their distribution in Taiwanese Kefir and Viili starters.

PubMed

Wang, S Y; Chen, H C; Liu, J R; Lin, Y C; Chen, M J

2008-10-01

The objective of the present study was to investigate yeast communities in kefir grains and viili starters in Taiwan through conventional microbiological cultivation and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The DNA sequencing was used as a validity technique to ensure that all isolates within each group belonged to just one species, and to confirm the identified results of PCR-DGGE. Results indicated that a combination of conventional microbiological cultivation with PCR-DGGE and sequencing could successfully identify 4 yeast species from both types of cultures in Taiwan. Kluyveromyces marxianus, Saccharomyces turicensis, and Pichia fermentans were found in Taiwanese kefir grains with a distribution of 76, 22, and 2%, respectively, whereas Klu. marxianus, Saccharomyces unisporus and P. fermentans were identified in viili starters corresponding to 58, 11, and 31% of the total cell counts, respectively. Furthermore, the culture-independent method was applied to identify the yeast species using DGGE. Only 2 yeast species, Klu. marxianus and S. turicensis, were found in kefir grains and 2, Klu. marxianus and P. fermentans, in viili starters. These results suggest that in samples containing multiple species, PCR-DGGE may fail to detect some species. Sequences of yeast isolates reported in this study have been deposited in the GenBank database under accession nos. DQ139802, AF398485, DQ377652, and AY007920.

Improved Physicochemical Properties of Yogurt Fortified with Fish Oil/γ-Oryzanol by Nanoemulsion Technology.

PubMed

Zhong, Jinfeng; Yang, Rong; Cao, Xiaoyi; Liu, Xiong; Qin, Xiaoli

2018-01-02

Fish oil has several dietary benefits, but its application in food formulations is limited because of its poor water-solubility, easy oxidation and strong odor. The purposes of this study were to produce a fish oil/γ-oryzanol nanoemulsion and to evaluate the effect of adding this nanoemulsion on the physicochemical and sensory characteristics of yogurts. Adding fish oil/γ-oryzanol nanoemulsion resulted in a significant reduction in the acidity and syneresis of yogurt. Yogurt with the nanoemulsion had significantly lower peroxide value (0.28 mmol/L after 21 days) and higher retention of eicosapentaenoic acid and docosahexaenoic acid contents (decreased to 95% and 94% of its initial value, respectively) than yogurt with fish oil/γ-oryzanol (peroxide value = 0.65 mmol/L; eicosapentaenoic acid and docosahexaenoic acid contents decreased to 72% and 53% of its initial value, respectively). Fish oil/γ-oryzanol nanoemulsion incorporated into yogurt had closer sensory attributes scores to plain yogurt. This study may have important implications for the application of fish oil/γ-oryzanol nanoemulsion in yogurt.

Characterization of starter kimchi fermented with Leuconostoc kimchii GJ2 and its cholesterol-lowering effects in rats fed a high-fat and high-cholesterol diet.

PubMed

Jo, Se Yeon; Choi, Eun A; Lee, Jae Joon; Chang, Hae Choon

2015-10-01

The hypocholesterolemic effects of lactic acid bacteria and kimchi have been demonstrated previously. However, the kimchi fermentation process still relies on naturally present microorganisms. To obtain functional kimchi with consistent quality, we validated the capacity of Leuconostoc kimchii GJ2 as a starter culture to control kimchi fermentation. Moreover, cholesterol-lowering effects of starter kimchi as a health-promoting product were explored. Bacteriocin production by Lc. kimchii GJ2 was highly enhanced in the presence of 5% Lactobacillus sakei NJ1 cell fractions. When kimchi was fermented with bacteriocin-enhanced Lc. kimchii GJ2, Lc. kimchii GJ2 became overwhelmingly predominant (98.3%) at the end of fermentation and maintained its dominance (up to 82%) for 84 days. Growing as well as dead cells of Lc. kimchii GJ2 showed high cholesterol assimilation (in vitro). Rats were fed a high-fat and high-cholesterol diet supplemented with starter kimchi. The results showed that feeding of starter kimchi significantly reduced serum total cholesterol, triglyceride and low-density lipoprotein cholesterol levels. Additionally, atherogenic index, cardiac risk factor and triglyceride and total cholesterol levels in liver and epididymal adipose tissue decreased significantly in rats fed starter kimchi. Kimchi fermented with Lc. kimchii GJ2 as a starter culture has efficient cholesterol-lowering effects. © 2014 Society of Chemical Industry.

Use of Tetragenococcus halophilus as a starter culture for flavor improvement in fish sauce fermentation.

PubMed

Udomsil, Natteewan; Rodtong, Sureelak; Choi, Yeung Joon; Hua, Yanglin; Yongsawatdigul, Jirawat

2011-08-10

The potential of Tetragenococcus halophilus as a starter culture for flavor improvement in fish sauce fermentation was elucidated. Four strains of T. halophilus isolated from fish sauce mashes were inoculated to anchovy mixed with 25% NaCl with an approximate cell count of 10(6) CFU/mL. The α-amino content of 6-month-old fish sauce samples inoculated with T. halophilus was 780-784 mM. The addition of T. halophilus MRC10-1-3 and T. halophilus MCD10-5-10 resulted in a reduction of histamine (P < 0.05). Fish sauce inoculated with T. halophilus showed high contents of total amino acids with predominantly high glutamic acid. Major volatile compounds in fish sauce were 2-methylpropanal, 2-methylbutanal, 3-methylbutanal, and benzaldehyde. T. halophilus-inoculated fish sauce samples demonstrated the ability to reduce dimethyl disulfide, a compound contributing to a fecal note. The use of T. halophilus for fish sauce fermentation improves amino acid profiles and volatile compounds as well as reduces biogenic amine content of a fish sauce product.

Amylose-potassium oleate inclusion complex in plain set-style yogurt

USDA-ARS?s Scientific Manuscript database

Amylose-potassium oleate inclusion complex (AIC) were used to replace skim milk solids in yogurt. The effect of AIC on yogurt fermentation and small amplitude oscillatory shear flow measurements of storage and loss moduli were studied and compared to full fat samples. Texture, storage modulus, and s...

A Multibacteriocin Cheese Starter System, Comprising Nisin and Lacticin 3147 in Lactococcus lactis, in Combination with Plantaricin from Lactobacillus plantarum

PubMed Central

Mills, S.; Griffin, C.; O'Connor, P. M.; Serrano, L. M.; Meijer, W. C.; Hill, C.

2017-01-01

ABSTRACT Functional starter cultures demonstrating superior technological and food safety properties are advantageous to the food fermentation industry. We evaluated the efficacies of single- and double-bacteriocin-producing starters of Lactococcus lactis capable of producing the class I bacteriocins nisin A and/or lacticin 3147 in terms of starter performance. Single producers were generated by mobilizing the conjugative bacteriophage resistance plasmid pMRC01, carrying lacticin genetic determinants, or the conjugative transposon Tn5276, carrying nisin genetic determinants, to the commercial starter L. lactis CSK2775. The effect of bacteriocin coproduction was examined by superimposing pMRC01 into the newly constructed nisin transconjugant. Transconjugants were improved with regard to antimicrobial activity and bacteriophage insensitivity compared to the recipient strain, and the double producer was immune to both bacteriocins. Bacteriocin production in the starter was stable, although the recipient strain proved to be a more efficient acidifier than transconjugant derivatives. Overall, combinations of class I bacteriocins (the double producer or a combination of single producers) proved to be as effective as individual bacteriocins for controlling Listeria innocua growth in laboratory-scale cheeses. However, using the double producer in combination with the class II bacteriocin producer Lactobacillus plantarum or using the lacticin producer with the class II producer proved to be most effective for reducing bacterial load. As emergence of bacteriocin tolerance was reduced 10-fold in the presence of nisin and lacticin, we suggest that the double producer in conjunction with the class II producer could serve as a protective culture providing a food-grade, multihurdle approach to control pathogenic growth in a variety of industrial applications. IMPORTANCE We generated a suite of single- and double-bacteriocin-producing starter cultures capable of generating the

Characterization of the antifungal activity of Lactobacillus harbinensis K.V9.3.1Np and Lactobacillus rhamnosus K.C8.3.1I in yogurt.

PubMed

Delavenne, Emilie; Cliquet, Sophie; Trunet, Clément; Barbier, Georges; Mounier, Jérôme; Le Blay, Gwenaëlle

2015-02-01

Few antifungal protective cultures adapted to fermented dairy products are commercially available because of the numerous constraints linked to their market implementation. Consumer's demand for naturally preserved food products is growing and the utilization of lactic acid bacteria is a promising way to achieve this goal. In this study, using a 2(5-1) factorial fractional design, we first evaluated the effects of fermentation time, of initial sucrose concentration and of the initial contamination amount of a spoilage yeast, on antifungal activities of single and mixed cultures of Lactobacillus rhamnosus K.C8.3.1I and Lactobacillus harbinensis K.V9.3.1Np in yogurt. L. harbinensis K.V9.3.1Np, the most relevant strain with regard to antifungal activity was then studied to determine its minimal inhibitory inoculation rate, its antifungal stability during storage and its impact on yogurt organoleptic properties. We showed that L. harbinensis K.V9.3.1Np maintained a stable antifungal activity over time, which was not affected by initial sucrose, nor by a reduction of the fermentation time. This inhibitory activity was an all-or-nothing phenomenon. Once L. harbinensis K.V9.3.1Np reached a population of ∼ 2.5 × 10(6) cfu/g of yogurt at the time of contamination, total inhibition of the yeast was achieved. We also showed that an inoculation rate of 5 × 10(6) cfu/ml in milk had no detrimental effect on yogurt organoleptic properties. In conclusion, L. harbinensis K.V9.3.1Np is a promising antifungal bioprotective strain for yogurt preservation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Microbiological and fermentative properties of baker's yeast starter used in breadmaking.

PubMed

Reale, A; Di Renzo, T; Succi, M; Tremonte, P; Coppola, R; Sorrentino, E

2013-08-01

This study assessed the levels of microbial contaminants in liquid, compressed and dry commercial baker's yeasts used as starters in breadmaking. Eumycetes, Enterobacteriaceae, total and fecal coliforms, Bacillus spp., and lactic acid bacteria (LAB), in particular enterococci, were quantified. Results obtained in this study highlighted that baker's yeast could represent a potential vehicle of spoilage and undesirable microorganisms into the baking environment, even if these do not influence the leavening activity in the dough, as ascertained by rheofermentometer analysis. Different microbial groups, such as spore-forming bacteria and moulds, were found in baker's yeast starters. Moreover, different species of LAB, which are considered the main contaminants in large-scale yeast fermentations, were isolated and identified by Denaturing Gradient Gel Electrophoresis (DGGE) and 16S rDNA sequencing. The most recurrent species were Lactobacillus plantarum, Enterococcus faecalis, and Enterococcus durans, isolated from both compressed and dry starters, whereas strains belonging to Leuconostoc and Pediococcus genera were found only in dry ones. Nested-Polymerase Chain Reaction (Nested-PCR) and Randomly Amplified Polymorphic DNA-PCR (RAPD-PCR) were also used to highlight the biodiversity of the different commercial yeast strains, and to ascertain the culture purity. © 2013 Institute of Food Technologists®

Effect of dairy powders fortification on yogurt textural and sensorial properties: a review.

PubMed

Karam, Marie Celeste; Gaiani, Claire; Hosri, Chadi; Burgain, Jennifer; Scher, Joël

2013-11-01

Yogurts are important dairy products that have known a rapid market growth over the past few decades. Industrial yogurt manufacture involves different processing steps. Among them, protein fortification of the milk base is elemental. It greatly enhances yogurt nutritional and functional properties and prevents syneresis, an undesirable yogurt textural defect. Protein enrichment can be achieved by either concentration process (evaporation under vacuum and membrane processing: reverse osmosis and/or ultrafiltration) or by addition of dairy ingredients. Traditionally, skim milk powder (SMP) is used to enrich the milk base before fermentation. However, increased quality and availability of other dairy ingredients such as milk protein isolates (MPI), milk protein concentrates (MPC) whey protein isolates (WPI) and concentrates (WPC), micellar casein (MC) and caseinates have promoted their use as alternatives to SMP. Substituting different dry ingredients for skim milk powder in yogurt making affects the yogurt mix protein composition and subsequent textural and sensorial properties. This review focuses on various type of milk protein used for fortification purposes and their influence on these properties.

Influence of hydrodynamic cavitation on the rheological properties and microstructure of formulated Greek-style yogurts.

PubMed

Meletharayil, G H; Metzger, L E; Patel, Hasmukh A

2016-11-01

With limited applications of acid whey generated during the manufacture of Greek yogurts, an alternate processing technology to sidestep the dewheying process was developed. Milk protein concentrate (MPC) and carbon dioxide-treated milk protein concentrate (TMPC) were used as sources of protein to fortify skim milk to 9% (wt/wt) protein for the manufacture of Greek-style yogurts (GSY). The GSY bases were inoculated and fermented with frozen direct vat set yogurt culture to a pH of 4.6. Owing to the difference in buffering of MPC and TMPC, GSY with TMPC and MPC exhibited different acidification kinetics, with GSY containing TMPC having a lower fermentation time. The GSY with TMPC had a titratable acidity of 1.45% lactic acid and was comparable to acidity of commercial Greek yogurt (CGY). Hydrodynamic cavitation at 4 different rotor speeds (0, 15, 30, and 60 Hz) as a postfermentation tool reduced the consistency coefficient (K) of GSY containing TMPC from 79.4 Pa·s n at 0 Hz to 17.59 Pa·s n at 60 Hz. Similarly for GSY containing MPC, K values decreased from 165.74 Pa·s n at 0 Hz to 53.04 Pa·s n at 60 Hz. The apparent viscosity (η 100 ) was 0.25 Pa·s for GSY containing TMPC and 0.66 Pa·s for GSY containing MPC at 60 Hz. The CGY had a η 100 value of 0.74 Pa·s. Small amplitude rheological analysis performed on GSY indicated a loss of elastic modulus dependency on frequency caused by the breakdown of protein interactions with increasing cavitator rotor speeds. A steady decrease in hardness and adhesiveness values of GSY was observed with increasing cavitational intensities. Numbers of grains with a perimeter of >1mm of cavitated GSY with TMPC and MPC were 35 and 13 grains/g of yogurt, respectively, and were lower than 293 grains/g observed in CGY. The water-holding capacity of GSY was higher than that observed for a commercial strained Greek yogurt. The ability to scale up the process of hydrodynamic cavitation industrially, and the ease of controlling events of

Utilization of konjac glucomannan as a fat replacer in low-fat and skimmed yogurt.

PubMed

Dai, Shuhong; Corke, Harold; Shah, Nagendra P

2016-09-01

Konjac glucomannan (KGM) has been reported to be beneficial to human health, as well as having potential functional properties as a fat replacer in dairy products. In this study, 0.5% KGM solution was added to prepare low-fat (LFKGM) and skimmed (SKKGM) yogurts, and their physicochemical properties were compared with those of full-fat yogurt control (FFC), low-fat yogurt control (LFC), and skimmed yogurt control (SKC). Properties and composition were determined and the microscopic structures of all yogurts were observed during storage at 4°C for 21d. Generally, addition of KGM to yogurts had no significant effect on composition, pH, and titratable acidity at each storage day. The LFKGM and SKKGM had higher whiteness, greenness, and yellowness hues compared with those of the LFC and SKC. The proteolysis of LFKGM and SKKGM was similar to that of FFC, whereas it was lower than in LFC and SKC after 14d of storage. Addition of KGM had no positive effects on the water-holding capacity, but led to a decrease in syneresis and spontaneous whey separation in LFKGM and SKKGM compared with those of LFC and SKC. The spontaneous whey separation of LFKGM was similar to that of FFC. Presence of KGM in skimmed yogurt affected textural characteristics, while having little effect on texture of low-fat yogurt. Additionally, LFKGM and SKKGM showed stronger and more stable gel structures than those of FFC, LFC, and SKC. Overall, no substantial changes were found in the characteristics for each yogurt during storage, except for pH and gel structures. Results indicated that KGM may be a good fat replacer to develop reduced-fat yogurts with desired characteristics. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Ionic solution and nanoparticle assisted MALDI-MS as bacterial biosensors for rapid analysis of yogurt.

PubMed

Lee, Chia-Hsun; Gopal, Judy; Wu, Hui-Fen

2012-01-15

Bacterial analysis from food samples is a highly challenging task because food samples contain intensive interferences from proteins and carbohydrates. Three different conditions of yogurt were analyzed: (1) the fresh yogurt immediately after purchasing, (2) the yogurt after expiry date stored in the refrigerator and (3) the yogurt left outside, without refrigeration. The shelf lives of both these yogurt was compared in terms of the decrease in bacterial signals. AB which initially contained 10(9) cells/mL drastically reduced to 10(7) cells/mL. However, Lin (Feng-Yin) yogurt which initially (fresh) had 10(8) cells/mL, even after two weeks beyond the expiry period showed no marked drop in bacterial count. Conventional MALDI-MS analysis showed limited sensitivity for analysis of yogurt bacteria amidst the complex milk proteins present in yogurt. A cost effective ionic solution, CrO(4)(2-) solution was used to enable the successful detection of bacterial signals (40-fold increased in sensitivity) selectively without the interference of the milk proteins. 0.035 mg of Ag nanoparticles (NPs) were also found to improve the detection of bacteria 2-6 times in yogurt samples. The current approach can be further applied as a rapid, sensitive and effective platform for bacterial analysis from food. Copyright © 2011 Elsevier B.V. All rights reserved.

Association between probiotic and yogurt consumption and kidney disease: insights from NHANES.

PubMed

Yacoub, Rabi; Kaji, Deepak; Patel, Shanti N; Simoes, Priya K; Busayavalasa, Deepthi; Nadkarni, Girish N; He, John C; Coca, Steven G; Uribarri, Jaime

2016-01-27

Data from experimental animals suggest that probiotic supplements may retard CKD progression. However, the relationship between probiotic use, frequent yogurt consumption (as a natural probiotic source), and kidney parameters have not been evaluated in humans. We utilized NHANES data, and analyzed the association of probiotic alone (1999-2012) and yogurt/probiotic (2003-2006) use with albuminuria and eGFR after adjustment for demographic and clinical parameters. Frequent yogurt consumption was defined as thrice or more weekly over the year prior to the interview. Frequent yogurt/probiotic consumers had lower adjusted odds of developing combined outcome (albuminuria and/or eGFR < 60 ml/min/1.73 m(2)) compared to infrequent consumers (OR = 0.76; 95 % CI = 0.61-0.94). When evaluated separately, frequent consumers had lower odds of albuminuria and nonsignificant trend towards decreased odds of low eGFR compared to infrequent consumers. In the probiotic cohort, probiotic consumers were found to have a lower adjusted odds of albuminuria compared to nonusers (OR = 0.59; 95 % CI = 0.37-0.94). Frequent yogurt and/or probiotics use is associated with decreased odds of proteinuric kidney disease. These hypothesis-generating results warrant further translational studies to further delineate the relationship between yogurt/probiotics with kidney dysfunction, as well as microbiome and dysbiosis as potential mediators.

Rheological and sensory performance of a protein-based sweetener (MNEI), sucrose, and aspartame in yogurt.

PubMed

Miele, Nicoletta A; Cabisidan, Erliza K; Blaiotta, Giuseppe; Leone, Serena; Masi, Paolo; Di Monaco, Rossella; Cavella, Silvana

2017-12-01

Sweeteners and flavors are generally added to yogurt to make them more palatable. However, the addition of these ingredients may affect the fermentation process of yogurt as well as its physical and sensory characteristics. Consumers prioritize yogurt products that are "natural." A modified single-chain form of the natural sweet protein monellin extracted from the fruit of Dioscoreophyllum cumminsii, called MNEI, could be a useful alternative to artificial sweeteners. The aim of the present work was to evaluate new rapid sensory methods in combination with rheology to assess the viability of using MNEI to develop sweetened yogurts without the calories of sugar. We studied the gelation and cooling kinetics of 4 yogurt samples (unsweetened or sweetened with MNEI, aspartame, or sucrose) by using a rheometer. Furthermore, the 4 yogurts, with and without addition of a flavoring agent, were characterized from a sensory perspective using a combination of 2 rapid sensory methods, ultra flash profile and flash profile. Rheological results showed that, when added at typical usage levels, aspartame, sucrose, and MNEI did not generally affect the yogurt fermentation process or its rheological properties. Sensory results demonstrated that texture attributes of yogurts with aspartame and sucrose were strongly linked to sweetness and flavor perception, but this was not true for MNEI-sweetened yogurts. In contrast to results obtained from samples sweetened with sucrose and aspartame, MNEI protein did not sweeten the yogurt when added before fermentation. This study highlights the enhancing effect of flavor on sweetness perception, supporting previous reports that noted synergistic effects between sucrose or aspartame and flavors. Hence, future studies should be conducted to determine how sweet proteins behave in yogurt when added after fermentation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of genetic type and casein haplotype on antioxidant activity of yogurts during storage.

PubMed

Perna, A; Intaglietta, I; Simonetti, A; Gambacorta, E

2013-06-01

The aim of this work was to investigate the antioxidant activity of yogurt made from the milk of 2 breeds-Italian Brown and Italian Holstein-characterized by different casein haplotypes (αS1-, β-, and κ-caseins) during storage up to 15 d. The casein haplotype was determined by isoelectric focusing; antioxidant activity of yogurt was measured using 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid). The statistical analysis showed a significant effect of the studied factors. Antioxidant activity increased during storage of both yogurt types, but yogurt produced with Italian Brown milk showed higher antioxidant activity than those produced with Italian Holstein milk. A high scavenging activity was present in yogurts with the allelic combination of BB-A(2)A(2)-BB. The results of this study suggest that the genetic type and the haplotype make a significant contribution in the production of yogurts with high nutraceutical value. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Microbiological characterization and functionality of set-type yogurt fermented with potential prebiotic substrates Cudrania tricuspidata and Morus alba L. leaf extracts.

PubMed

Oh, Nam Su; Lee, Ji Young; Joung, Jae Yeon; Kim, Kyung Su; Shin, Yong Kook; Lee, Kwang-Won; Kim, Sae Hun; Oh, Sangnam; Kim, Younghoon

2016-08-01

The objective of this study was to investigate the effect of 2 plant leaf extracts on fermentation mechanisms and health-promoting activities and their potential as a nutraceutical prebiotics ingredient for application in dairy products. The individual active phenolic compounds in the plant extract-supplemented milk and yogurts were also identified. Compared with control fermentation, the plant extracts significantly increased the growth and acidification rate of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. In particular, plant extract components, including monosaccharides, formic acid, and hydroxycinnamic acid, such as neo-chlorogenic, chlorogenic, and caffeic acid, together play a stimulatory role and cause this beneficial effect on the growth of yogurt culture bacteria through fermentation. In addition, supplementation with the plant extracts enhanced antioxidant activities with increased total phenolic contents, especially the highest antioxidant activity was observed in yogurt supplemented with Cudrania tricuspidata leaf extract. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Passion fruit by-product and fructooligosaccharides stimulate the growth and folate production by starter and probiotic cultures in fermented soymilk.

PubMed

Albuquerque, Marcela Albuquerque Cavalcanti; Bedani, Raquel; LeBlanc, Jean Guy; Saad, Susana Marta Isay

2017-11-16

Two starter cultures (Streptococcus (St.) thermophilus ST-M6 and TA-40) and five probiotic strains (St. thermophilus TH-4, Lactobacillus (Lb.) acidophilus LA-5, Lb. rhamnosus LGG, Lb. fermentum PCC, and Lb. reuteri RC-14) were used to ferment different soymilk formulations supplemented with passion fruit by-product and/or fructo-oligosaccharides (FOS) with the aim of increasing folate concentrations. Growth and folate production of individual strains were evaluated and the results used to select co-cultures. Both St. thermophilus ST-M6 and TH-4 were the best folate producers and were able to increase the folate content of all soymilk formulations when used alone or in co-culture with lactobacilli strains, especially in the presence of both passion fruit by-product and FOS. Thus, passion fruit by-product and FOS could be used as dietary ingredients to stimulate the folate production by selected bacterial strains during the fermentation of soymilk. It was also shown that vitamin production by microorganisms is strain-dependent and may also be influenced by nutritional and environmental conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Frozen yogurt with added inulin and isomalt.

PubMed

Isik, U; Boyacioglu, D; Capanoglu, E; Erdil, D Nilufer

2011-04-01

The objective of this study was to produce a frozen yogurt containing low fat and no added sugar. Samples containing 5% polydextrose, 0.065% aspartame and acesulfame-K mixture, and different levels of inulin and isomalt (5.0, 6.5, and 8.0%) were produced at pilot scale and analyzed for their physical and chemical properties including proximate composition, viscosity, acidity, overrun, melting rate, heat shock stability, as well as sensory characteristics, and viability of lactic acid bacteria. With the addition of inulin and isomalt, viscosity increased by 19 to 52% compared with that of sample B (reduced-fat control). The average calorie values of samples substituted with sweeteners were about 43% lower than that of original sample. Low-calorie frozen yogurt samples melted about 33 to 48% slower than the reduced-fat control sample at 45 min. Based on quantitative descriptive profile test results, statistically significant differences among products were observed for hardness, iciness, foamy melting, whey separation, and sweetness characteristics. The results of principal component analysis showed that the sensory properties of the sample containing 6.5% inulin and 6.5% isomalt were similar to those of control. Lactic acid bacteria counts of frozen yogurt were found to be between 8.12 and 8.49 log values, 3 mo after the production. The overall results showed that it is possible to produce an attractive frozen yogurt product with the incorporation of inulin and isomalt with no added sugar and reduced fat. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Evaluation of Bacillus spp. as dough starters for Adhirasam - A traditional rice based fermented food of Southern India.

PubMed

Anisha, Anvar Hussain Noorul; Anandham, Rangasamy; Kwon, Soon Woo; Gandhi, Pandiyan Indira; Gopal, Nellaiappan Olaganathan

2015-01-01

Adhirasam is a cereal based, doughnut shaped, deep fried dessert consumed in the southern regions of India. The dough used to prepare adhirasam is fermented and contains rice flour and jaggery. The aim of the present study was to characterize the cultivable bacteria associated with this fermented dough and to identify a suitable starter culture for the production of quality adhirasam. In total, one hundred and seventy bacterial isolates were recovered from de Man Rogosa Sharp (MRS) agar, nutrient agar, lysogeny agar and tryptic soy agar media. Out of the 170 bacterial isolates, sixteen isolates were selected based on their ability to tolerate glucose and sucrose. All the bacterial isolates tolerated 15% glucose and 30% sucrose. Analyses of 16S rDNA gene sequences of the bacterial isolates showed that the dominant cultivable bacteria were members of the genus Bacillus. These strains were further used as starters and tested for their ability to ferment rice flour with jaggery to produce adhirasam dough. Organoleptic evaluation was carried out to choose the best starter strain. Adhirasam prepared from Bacillus subtilis isolates S4-P11, S2-G2-A1 and S1-G15, Bacillus tequilensis isolates S2-H16, S3-P9, S3-G10 and Bacillus siamensis isolate S2-G13 were highly acceptable to consumers. Adhirasam prepared using these starter cultures had superior product characteristics such as softness in texture, flavor and enhanced aroma and sweet taste.

Evaluation of Bacillus spp. as dough starters for Adhirasam - A traditional rice based fermented food of Southern India

PubMed Central

Anisha, Anvar Hussain Noorul; Anandham, Rangasamy; Kwon, Soon Woo; Gandhi, Pandiyan Indira; Gopal, Nellaiappan Olaganathan

2015-01-01

Abstract Adhirasam is a cereal based, doughnut shaped, deep fried dessert consumed in the southern regions of India. The dough used to prepare adhirasam is fermented and contains rice flour and jaggery. The aim of the present study was to characterize the cultivable bacteria associated with this fermented dough and to identify a suitable starter culture for the production of quality adhirasam. In total, one hundred and seventy bacterial isolates were recovered from de Man Rogosa Sharp (MRS) agar, nutrient agar, lysogeny agar and tryptic soy agar media. Out of the 170 bacterial isolates, sixteen isolates were selected based on their ability to tolerate glucose and sucrose. All the bacterial isolates tolerated 15% glucose and 30% sucrose. Analyses of 16S rDNA gene sequences of the bacterial isolates showed that the dominant cultivable bacteria were members of the genus Bacillus. These strains were further used as starters and tested for their ability to ferment rice flour with jaggery to produce adhirasam dough. Organoleptic evaluation was carried out to choose the best starter strain. Adhirasam prepared from Bacillus subtilis isolates S4-P11, S2-G2-A1 and S1-G15, Bacillus tequilensis isolates S2-H16, S3-P9, S3-G10 and Bacillus siamensis isolate S2-G13 were highly acceptable to consumers. Adhirasam prepared using these starter cultures had superior product characteristics such as softness in texture, flavor and enhanced aroma and sweet taste. PMID:26691480

Characterisation and biochemical properties of predominant lactic acid bacteria from fermenting cassava for selection as starter cultures.

PubMed

Kostinek, M; Specht, I; Edward, V A; Pinto, C; Egounlety, M; Sossa, C; Mbugua, S; Dortu, C; Thonart, P; Taljaard, L; Mengu, M; Franz, C M A P; Holzapfel, W H

2007-03-20

the 32 a total of 16 strains were finally selected for the development as starter cultures for Gari production.

Optimization of an organic yogurt based on sensorial, nutritional, and functional perspectives.

PubMed

Karnopp, Ariadne Roberto; Oliveira, Katherine Guimarães; de Andrade, Eriel Forville; Postingher, Bruna Mara; Granato, Daniel

2017-10-15

The effects of purple grape juice (PGJ), grape skin flour (GSF), and oligofructose (OLI) on proximate composition, total phenolic content (TPC), antioxidant activity (AA), sensory, physicochemical, and textural properties of yogurts were analyzed using response surface methodology. Multiple regression models were proposed and results showed that PGJ increased the viscosity, AA, and TPC, while GSF increased the ash and total fiber contents of yogurts. GSF and OLI increased the hardness and consistency. A simultaneous optimization was performed to maximize TPC, ash and fibers contents, and sensory acceptance: a yogurt containing 1.7% GSF and 8.0% PGJ had a high fiber (5.60±0.13%) and ash (0.76±0.02%) contents, TPC (28.32±2.10mg GAE/100g), AA toward DPPH (57.85±1.36mg AAE/100g), and total reducing capacity (28.86±5.19mg QE/100g). The optimized yogurt had 79% acceptability index, indicating the use of PGJ and GSF is a feasible alternative to increase the functional properties of yogurts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reduction of the degradation activity of umami-enhancing purinic ribonucleotide supplement in miso by the targeted suppression of acid phosphatases in the Aspergillus oryzae starter culture.

PubMed

Marui, Junichiro; Tada, Sawaki; Fukuoka, Mari; Wagu, Yutaka; Shiraishi, Yohei; Kitamoto, Noriyuki; Sugimoto, Tatsuya; Hattori, Ryota; Suzuki, Satoshi; Kusumoto, Ken-Ichi

2013-09-02

Miso (fermented soybean paste) is a traditional Japanese fermented food, and is now used worldwide. The solid-state culture of filamentous fungus, Aspergillus oryzae, grown on rice is known as rice-koji, and is important as a starter for miso fermentation because of its prominent hydrolytic enzyme activities. Recently, commercial miso products have been supplemented with purinic ribonucleotides, such as inosine monophosphate (IMP) and guanine monophosphate, to enhance the characteristic umami taste of glutamate in miso. Because the purinic ribonucleotides are degraded by enzymes such as acid phosphatases in miso, heat inactivation is required prior to the addition of these flavorings. However, heat treatment is a costly process and reduces the quality of miso. Therefore, an approach to lower acid phosphatase activities in koji culture is necessary. Transcriptional analysis using an A. oryzae KBN8048 rice-koji culture showed that eight of the 13 acid phosphatase (aph) genes were significantly down-regulated by the addition of phosphoric acid in the preparation of the culture in a concentration-dependent manner, while aphC expression was markedly up-regulated under the same conditions. The eight down-regulated genes might be under the control of the functional counterpart of the Saccharomyces cerevisiae transcriptional activator Pho4, which specifically regulates phosphatase genes in response to the ambient phosphate availability. However, the regulatory mechanism of aphC was not clear. The IMP dephosphorylation activities in rice-koji cultures of KBN8048 and the aphC deletion mutant (ΔaphC) were reduced by up to 30% and 70%, respectively, in cultures with phosphoric acid, while protease and amylase activity, which is important for miso fermentation, was minimally affected. The miso products fermented using the rice-koji cultures of KBN8048 and ΔaphC prepared with phosphoric acid had reductions in IMP dephosphorylation activity of 80% and 90%, respectively, without

Study on fast measurement of sugar content of yogurt using Vis/NIR spectroscopy techniques

NASA Astrophysics Data System (ADS)

He, Yong; Feng, Shuijuan; Wu, Di; Li, Xiaoli

2006-09-01

In order to measuring the sugar content of yogurt rapidly, a fast measurement of sugar content of yogurt using Vis/NIR-spectroscopy techniques was established. 25 samples selected separately from five different brands of yogurt were measured by Vis/NIR-spectroscopy. The sugar content of yogurt on positions scanned by spectrum were measured by a sugar content meter. The mathematical model between sugar content and Vis/NIR spectral measurements was established and developed based on partial least squares (PLS). The correlation coefficient of sugar content based on PLS model is more than 0.894, and standard error of calibration (SEC) is 0.356, standard error of prediction (SEP) is 0.389. Through predicting the sugar content quantitatively of 35 samples of yogurt from 5 different brands, the correlation coefficient between predictive value and measured value of those samples is more than 0.934. The results show the good to excellent prediction performance. The Vis/NIR spectroscopy technique had significantly greater accuracy for determining the sugar content. It was concluded that the Vis/NIRS measurement technique seems reliable to assess the fast measurement of sugar content of yogurt, and a new method for the measurement of sugar content of yogurt was established.

Effect of diacetyl on controlling Escherichia coli O157:H7 and Salmonella Typhimurium in the presence of starter culture in a laboratory medium and during meat fermentation.

PubMed

Kang, D H; Fung, D Y

1999-09-01

Diacetyl is a flavor compound that possesses antimicrobial activity and is found in several dairy products. The effect of diacetyl on controlling the growth of two foodborne pathogens, Escherichia coli O157:H7 and Salmonella Typhimurium, when grown with Pediococcus acidilactici as a meat starter culture was evaluated in a laboratory medium and during salami fermentation. Diacetyl (50 ppm) added to each mixed culture system strongly inhibited the growth of E. coli O157:H7 and Salmonella Typhimurium in the laboratory medium (brain heart infusion, 2.3% of NaCl, 0.75% of dextrose) (P < 0.05). During meat fermentation, the growth of E. coli O157:H7 and Salmonella Typhimurium was inhibited significantly by addition of diacetyl (300 ppm) (P < 0.05) after 24 h fermentation. However, the acid production and growth of P. acidilactici were not affected by the addition of diacetyl (P > 0.05). After 24 h meat fermentation, about a 1.0-log CFU/g difference occurred in numbers of each foodborne pathogen mixed with P. acidilactici (P < 0.05) with and without 300 ppm diacetyl. Diacetyl and the acid produced by the meat starter culture reduced the growth of the two foodborne pathogens during salami fermentation. These results suggest that diacetyl can be used as a food ingredient during meat fermentation to control E. coli O157:H7 and Salmonella Typhimurium without harmful effects on the growth and acid production of P. acidilactici.

Physicochemical, microbial, and sensory properties of nanopowdered eggshell-supplemented yogurt during storage.

PubMed

Al Mijan, Mohammad; Choi, Kyung-Hoon; Kwak, Hae-Soo

2014-01-01

This study was carried out to investigate the possibility of adding nanopowdered eggshell (NPES) into yogurt to improve the functionality of yogurt and the effects of adding NPES on the physicochemical, microbial, and sensory properties of the products during storage. The pH and mean lactic acid bacteria counts of NPES-added (0.15-0.45%, wt/vol) yogurt ranged from 4.31 to 4.66 and from 6.56 × 10(8) to 8.56 × 10(8)cfu/mL, respectively, whereas these values ranged from 4.13 to 4.44 and 8.46 × 10(8) to 1.39 × 10(9), respectively, for the control samples during storage at 5 °C for 16d, which indicates a prolonged shelf-life with NPES-supplemented yogurt. Color analysis showed that the lightness (L*) and position between red and green (a*) values were not significantly influenced by the addition of NPES. However, the position between yellow and blue (b*) value significantly increased with the addition of the concentration (0.45%, wt/vol) of NPES at d 16 of storage. Sensory evaluation revealed that NPES-added yogurts showed a notably less sourness score and a higher astringency score than the control. An earthy flavor was higher in 0.45% NPES-supplemented yogurt compared with the control. Based on the results obtained from the current study, the concentration (0.15 to 0.30%, wt/vol) of NPES can be used to formulate NPES-supplemented yogurt without any significant adverse effects on the physicochemical, microbial, and sensory properties. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Comparison of biotransformation of inorganic selenium by Lactobacillus and Saccharomyces in lactic fermentation process of yogurt and kefir.

PubMed

Alzate, A; Fernández-Fernández, A; Pérez-Conde, M C; Gutiérrez, A M; Cámara, C

2008-09-24

The aim of the present study was to characterize, quantify, and compare the different selenium species that are produced when lactic fermentation with two different types of microorganisms, bacteria (Lactobacillus) and yeast (Saccharomyces), take place to produce yogurt and kefir, respectively, and to study the transformation process of these species as a function of time. These two dairy products were chosen for the study because they are highly consumed in different cultures. Moreover, the microorganisms present in the fermentation processes are different. While the bacteria Lactobacillus is the one responsible for yogurt fermentation, a partnership between bacteria and the yeast Saccharomyces causes kefir fermentation. A comparative study has been carried out by fermenting Se(IV) enriched milk in the presence of both types of microorganisms, where the concentration range studied was from 0.5 to 20 microg g (-1). Enzymatic extraction enabled selenium speciation profiles, obtained by anionic exchange and ion-pairing reversed phase high performance liquid chromatography (IP-RP-HPLC) with inductively coupled plasma mass spectrometry (ICP-MS) detection. Scanning electron microscopy (SEM) applied to the enriched samples showed segregated Se (0), at added concentrations higher than 5 microg g (-1). The main Se species formed depended on the type of microorganism involved in the fermentation process, SeCys 2 and MeSeCys being the main species generated in yogurt and SeMet in kefir. The results obtained are different for both kinds of samples. Lactic fermentation for yogurt produced an increment in selenocystine (SeCys 2) and Se-methylselenocysteine (MeSeCys), while fermentation to produce kefir also incremented the selenomethionine (SeMet) concentration. The Se species are stable for at least 10 and 15 days for kefir and yogurt, respectively. After this period, selenocystine concentration decreased, and the concentration of Se-methylselenocysteine was found to

Silent Starters

ERIC Educational Resources Information Center

Morris, Emma

2011-01-01

The "silent starter" is an idea that the author was reminded of during Christopher Martin's session at the ATM conference in 2011, entitled "Big Ideas". This was a nice idea for introducing, or practising mappings, but it was not the first time the author had encountered this powerful teaching tool. The idea is best explained…

30 CFR 75.819 - Motor-starter enclosures; barriers and interlocks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Motor-starter enclosures; barriers and...-Voltage Distribution High-Voltage Longwalls § 75.819 Motor-starter enclosures; barriers and interlocks. Compartment separation and cover interlock switches for motor-starter enclosures must be maintained in...

Effects of storage and yogurt matrix on the stability of tocotrienols encapsulated in chitosan-alginate microcapsules.

PubMed

Tan, Phui Yee; Tan, Tai Boon; Chang, Hon Weng; Tey, Beng Ti; Chan, Eng Seng; Lai, Oi Ming; Baharin, Badlishah Sham; Nehdi, Imededdine Arbi; Tan, Chin Ping

2018-02-15

Tocotrienol microcapsules (TM) were formed by firstly preparing Pickering emulsion containing tocotrienols, which was then gelled into microcapsules using alginate and chitosan. In this study, we examined the stability of TM during storage and when applied into a model food system, i.e. yogurt. During storage at 40°C, TM displayed remarkably lower tocotrienols loss (50.8%) as compared to non-encapsulated tocotrienols in bulk oil (87.5%). When the tocotrienols were incorporated into yogurt, the TM and bulk oil forms showed a loss of 23.5% and 81.0%, respectively. Generally, the tocotrienols were stable in the TM form and showed highest stability when these TM were added into yogurt. δ-Tocotrienol was the most stable isomer in both forms during storage and when incorporated into yogurt. The addition of TM into yogurt caused minimal changes in the yogurt's color and texture but slightly altered the yogurt's viscosity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysis of a food-borne fungal pathogen outbreak: virulence and genome of a Mucor circinelloides isolate from yogurt.

PubMed

Lee, Soo Chan; Billmyre, R Blake; Li, Alicia; Carson, Sandra; Sykes, Sean M; Huh, Eun Young; Mieczkowski, Piotr; Ko, Dennis C; Cuomo, Christina A; Heitman, Joseph

2014-07-08

. circinelloides, a mucoralean fungal pathogen, and >200 consumers complained of symptoms, including vomiting, nausea, and diarrhea. The manufacturer voluntarily withdrew the affected yogurt products from the market. Compared to other food-borne pathogens, including bacteria, viruses, and parasites, less focus has been placed on the risk of fungal pathogens. This study evaluates the potential risk from the food-borne fungal pathogen M. circinelloides that was isolated from the contaminated commercial yogurt. We successfully cultured an M. circinelloides isolate and found that the isolate belongs to the species M. circinelloides f. circinelloides, which is often associated with human infections. In murine and insect host models, the isolate was virulent. While information disseminated in the popular press would suggest this fungal contaminant poses little or no risk to consumers, our results show instead that it is capable of causing significant infections in animals. Copyright © 2014 Lee et al.

Fortification of yogurts with different antioxidant preservatives: A comparative study between natural and synthetic additives.

PubMed

Caleja, Cristina; Barros, Lillian; Antonio, Amilcar L; Carocho, Márcio; Oliveira, M Beatriz P P; Ferreira, Isabel C F R

2016-11-01

Consumers demand more and more so-called "natural" products and, therefore, the aim of this work was to compare the effects of natural versus synthetic antioxidant preservatives in yogurts. Matricaria recutita L. (chamomile) and Foeniculum vulgare Mill. (fennel) decoctions were tested as natural additives, while potassium sorbate (E202) was used as a synthetic additive. The fortification of yogurts with natural and synthetic antioxidants did not cause significant changes in the yoghurt pH and nutritional value, in comparison with control samples (yogurt without any additive). However, the fortified yogurts showed higher antioxidant activity, mainly the yogurts with natural additives (and among these, the ones with chamomile decoction). Overall, it can be concluded that plant decoctions can be used to develop novel yogurts, by replacing synthetic preservatives and improving the antioxidant properties of the final product, without changing the nutritional profile. Copyright © 2016 Elsevier Ltd. All rights reserved.

Developing a prebiotic yogurt enriched by red bean powder: Microbiological, physi-cochemical and sensory aspect

NASA Astrophysics Data System (ADS)

Setiyoningrum, Fitri; Priadi, Gunawan; Afiati, Fifi

2017-01-01

Red bean is widely known as a prebiotic, but addition of it into yogurt is rare. The aim of this study was to evaluate the effect of red bean powder addition on microbiological, physicochemical, and sensory of yogurt. Skim milk also added into yogurt formula to optimize the quality of yogurt. The treatment of concentrations, either red bean and skim milk, did not effect on the viability of lactic acid bacteria of yogurt (8.35 - 9.03 log cfu/ml) and the crude fiber content (0.04 - 0.08%). The increasing of red bean concentration induced the increase of protein content significantly. The increasing of level concentration, either red bean or skim milk, induced the increasing of carbohydrate content. Opposite phenomenon was occurred on the moisture content. Based on the sensory test result, the addition of 3% of skim milk and 2%of red bean into yogurt still accepted by panelist.

Crankshaft position sensing with combined starter alternator

DOEpatents

Brandenburg, Larry Raymond; Miller, John Michael

2000-06-13

A crankshaft position sensing apparatus for use with an engine (16) having a combined starter/alternator assembly (18). The crankshaft position sensing apparatus includes a tone ring (38) with a sensor (36) and bandpass filter (46), having a cylinder identification input from a camshaft sensor (48), and a gain limiter (54). The sensing apparatus mounts near the rotor (30) of the combined starter/alternator assembly (18). The filtered crankshaft position signal can then be input into a vehicle system controller (58) and an inner loop controller (60). The starter/alternator assembly (18) in combination with an internal combustion engine is particularly useful for a hybrid electric vehicle system.

Evidence for the effects of yogurt on gut health and obesity.

PubMed

Pei, Ruisong; Martin, Derek A; DiMarco, Diana M; Bolling, Bradley W

2017-05-24

Obesity is associated with increased risk for chronic diseases, and affects both developed and developing nations. Yogurt is a nutrient-dense food that may benefit individuals with lactose intolerance, constipation and diarrheal diseases, hypertension, cardiovascular diseases, diabetes, and certain types of cancer. Emerging evidence suggests that yogurt consumption might also improve the health of obese individuals. Obesity is often accompanied by chronic, low-grade inflammation perpetuated by adipose tissue and the gut. In the gut, obesity-associated dysregulation of microbiota and impaired gut barrier function may increase endotoxin exposure. Intestinal barrier function can be compromised by pathogens, inflammatory cytokines, endocannabinoids, diet, exercise, and gastrointestinal peptides. Yogurt consumption may improve gut health and reduce chronic inflammation by enhancing innate and adaptive immune responses, intestinal barrier function, lipid profiles, and by regulating appetite. While this evidence suggests that yogurt consumption is beneficial for obese individuals, randomized-controlled trials are needed to further support this hypothesis.

Effect of Novel Starter Culture on Reduction of Biogenic Amines, Quality Improvement, and Sensory Properties of Doenjang, a Traditional Korean Soybean Fermented Sauce Variety.

PubMed

Shukla, Shruti; Lee, Jong Suk; Park, Hae-Kyong; Yoo, Jung-Ah; Hong, Sung-Yong; Kim, Jong-Kyu; Kim, Myunghee

2015-08-01

To select appropriate microorganisms as starter cultures for the reliable and reproducible fermentation of soybean fermented products of Korean Doenjang, various ratios of fungi (Aspergillus oryzae J, Mucor racemosus 15, M. racemosus 42) combined with Bacillus subtilis TKSP 24 were selected as either single, double, or multiple Meju strains for commercial mass production of Doenjang, followed by analysis of sensory characteristics. In the sensory evaluation, Doenjang BAM15-1 and BAM42-1, which were fermented with multiple strains (1:1:1), showed the highest sensory scores as compared to control. Based on sensory characteristics, 6 Doenjang samples were subjected to quantitative determination of amino acids, free sugars, and organic acids (volatile and nonvolatile) contents, followed by determination of biogenic amines. Total sweet taste amino acid contents were highest in BAM15-1 and BAM42-1 samples (333.7 and 295.8 mg/100 g, respectively) and similar that of control (391.1 mg/100 g). Samples BAM15-1 and BAM42-1 showed the relatively high volatile and nonvolatile organic acid contents (154.24, 192.26, and 71.31, 82.42 mg/100 g, respectively). In addition, BAM15-1 and BAM42-1 showed negligible biogenic amine formation, ranging from 0.00 to 1.02 and 0.00 to 3.92 mg/100 g, respectively. These findings indicate that determination of food components along with sensory and quality attributes using multiple microbial Meju strains as a starter culture may provide substantial results on improved quality fermented Doenjang products. © 2015 Institute of Food Technologists®

Nano-encapsulation of fish oil in nano-liposomes and its application in fortification of yogurt.

PubMed

Ghorbanzade, Tahere; Jafari, Seid Mahdi; Akhavan, Sahar; Hadavi, Roxana

2017-02-01

Fish oils have many dietary benefits, but due to their strong odors and rapid deterioration, their application in food formulations is limited. For these reasons, nano-liposome was used to nano-encapsulate fish oil in this study and encapsulated fish oil was utilized in fortifying yogurt. Physicochemical properties of produced yogurt including pH, acidity, syneresis, fatty acid composition, peroxide value as well as sensory tests were investigated during three weeks storage at 4°C. Nano-liposome encapsulation resulted in a significant reduction in acidity, syneresis and peroxide value. The results of gas chromatography analyses revealed that after 21days storage, yogurt fortified with nano-encapsulated fish oil had a higher DHA and EPA contents than yogurt containing free fish oil. Overall, the results of this study indicates that adding nano-encapsulated fish oil into yogurt gave closer characteristics to control sample in terms of sensory characteristics than yogurt fortified with free fish oil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of cyclodextrins on the flavor of goat milk and its yogurt.

PubMed

Young, O A; Gupta, R B; Sadooghy-Saraby, S

2012-02-01

Goat milk fat includes several branched chain fatty acids (BCFAs), like 4-methyloctanoic acid, which when free, are responsible for goaty flavor. This flavor limits the market opportunities for goat milk. Prior research showed that cyclodextrins (CDs) can reduce goaty flavor, presumably by binding free fatty acids. This research extends that observation. In odor ranking trials in citrate buffer at pH 4.8, β-CD concentrations between 0% and 0.35% were increasingly effective in reducing odor intensity due to 4-methyloctanoic acid, but only when present in high molar excess. α-CD was also effective, but γ-CD was not. In lipase-treated goat milk only β-CD was effective but at much lower molar excess, a difference potentially explained by several factors. One was that BCFAs bind to CDs in marked preference to their straight chain isomers. Displacement experiments with phenolphthalein disproved that hypothesis. The ability of β-CD to reduce goaty flavor intensity extended to yogurt. An analytical panel showed that flavor of goat yogurt was reduced by addition of β-CD, but only if added before heating and fermentation. A hedonic trial showed that consumers preferred unsweetened and sweet/vanilla-flavored goat yogurt more when β-CD was included, P = 0.004 and 0.016, respectively. Males liked all yogurts more than females (P < 0.01), but there was a treatment × gender interaction (P = 0.016) for sweet/vanilla yogurt: sweet/vanilla masked the goaty flavor for males but not females. This results parallels previously demonstrated gender effects for sheepmeat flavor caused by BCFAs. β-Cyclodextrin masks goaty flavor in yogurt, and with its GRAS status means it could be used in commercial goat yogurts and similar products so the real or perceived nutritional advantages of goat milk are not lost to goaty flavor. © 2012 Institute of Food Technologists®

Dual functionality of triticale as a novel dietary source of prebiotics with antioxidant activity in fermented dairy products.

PubMed

Agil, Rania; Hosseinian, Farah

2012-03-01

The objectives of this study were to: (i) define the optimum concentration of triticale bran (TB) that can be incorporated in yogurt, (ii) evaluate the prebiotic effects of TB on microbial viability, pH and total titratable acidity (TTA) in yogurt across 28 days of cold storage, and (iii) measure the oxygen radical absorbance capacity (ORAC) of water-extractable polysaccharides (WEP) in TB. Lactobacillus bulgaricus and Streptococcus thermophilus were used as starter cultures. Lactobacillus acidophilus and Bifidobacterium lactis were used as probiotics. A concentration of 4% TB in yogurt was determined to be the maximum amount that could be added without causing synersis. By day 7, the number of bacteria greatly increased in yogurt samples containing TB and maintained higher viable bacteria counts at the end of the cold storage period, in comparison to controls (P ≤ 0.05). Confirming this data was the lower pH levels and higher TTA values of TB yogurt samples exhibited throughout 28 days (P ≤ 0.05). Polysaccharide extracts of TB exhibited strong antioxidant activity with an ORAC value of 33.86 ± 2.30 μmol trolox equivalents (TE)/g of bran. Results of this study suggest that TB may serve as a new prebiotic and antioxidant source for functional foods and nutraceutical applications.

Relevance of the Mention of Antioxidant Properties in Yogurt Labels: In Vitro Evaluation and Chromatographic Analysis.

PubMed

Pereira, Eliana; Barros, Lillian; Ferreira, Isabel C F R

2013-06-18

The purpose of the inclusion of fruit (natural additives) in yogurt aims to increase its antioxidant activity and functionality. Herein, a comparative study of the antioxidant potential of yogurts with pieces of various fruits was performed, including yogurts with mention of antioxidant properties in the label. Free radicals scavenging activity, reducing power and inhibition of lipid peroxidation were evaluated by in vitro assays, as were the contents in antioxidants such as phenolics, flavonoids, sugars and tocopherols. After analyzing thirteen yogurts containing fruit pieces and a natural one (control), the most interesting were yogurts with pieces of berries (for phenolics, flavonoids and 2,2-dipheny-1-picrylhydrazyl (DPPH) scavenging activity), pineapple (for reducing power), blackberry (for β-carotene bleaching inhibition), blackberry "antioxidant" (for tocopherols) and cherry (for sugars). The mention of "antioxidant" in the label was relevant for tocopherols, sugars, DPPH scavenging activity and reducing power. No synergisms were observed in yogurts prepared with pieces of different fruits. Nevertheless, the addition of fruit pieces to yogurt was favorable for antioxidant content, increasing the protection of the consumer against diseases related to oxidative stress.

Characterization of certain bacterial strains for potential use as starter or probiotic cultures in dairy products.

PubMed

Monteagudo-Mera, A; Caro, I; Rodríguez-Aparicio, L B; Rúa, J; Ferrero, M A; García-Armesto, M R

2011-08-01

The present work was aimed at characterizing 12 strains of lactic acid bacteria (LAB) to obtain improved potential starter or probiotic cultures that could be used for making dairy products from ewe's milk and cow's milk. Eight strains with antimicrobial properties, isolated from ewe's milk and from cheese made from ewe's and/or cow's milk, were studied. They were identified as Enterococcus faecalis (five strains), Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides, and Lactobacillus paracasei subsp. paracasei (one strain of each species). Additionally, four strains were obtained from the American Type Culture Collection: Lactobacillus casei 393 (isolated from cheese), L. lactis subsp. lactis 11454 (origin nonspecified and a producer of nisin), and two strains isolated from human feces (L. paracasei subsp. paracasei 27092 and Lactobacillus rhamnosus 53103, antibacterial agent producer). All E. faecalis strains showed at least one virulence factor (either hemolysin or gelatinase), which emphasizes the importance of these studies in this species. Both L. lactis strains and most Lactobacillus spp. were good acidifiers in ewe's milk and cow's milk at 30°C. High β-galactosidase activity, as well as aminopeptidase activities that favor the development of desirable flavors in cheese, were detected in all Lactobacillus spp. strains. Furthermore, L. rhamnosus ATCC 53103 showed α-fucosidase activity (thought to help colonization of the intestine) and lack of α-glucosidase activity (a trait considered positive for diabetic and obese humans). This last enzymatic activity was also lacking in L. lactis ATCC 11454. L. mesenteroides was the only strain D(2)-lactic acid producer. The selection of any particular strain for probiotic or dairy cultures should be performed according to the technological and/or functional abilities needed.

Yogurt for treating antibiotic-associated diarrhea: Systematic review and meta-analysis.

PubMed

Patro-Golab, Bernadeta; Shamir, Raanan; Szajewska, Hania

2015-06-01

Antibiotic-associated diarrhea (AAD) is a common complication in individuals treated with antibiotics. The aim of this review was to systematically evaluate the efficacy of yogurt consumption for the prevention of AAD. In this systematic review, a number of databases including MEDLINE, EMBASE, and the Cochrane Library, with no language restrictions, were searched up to September 2014 for randomized controlled trials (RCTs) evaluating the effect of yogurt consumption in adults and children who were receiving antibiotics. The risk for bias was assessed using the Cochrane risk of bias tool. Two RCTs, both low in methodological quality, were included. Compared with no intervention, yogurt consumption reduced the risk for diarrhea in the fixed effect model (two RCTs, n = 314, relative risk [RR], 0.56; 95% confidence interval [CI], 0.31-1.00). Significant heterogeneity between the trials was detected (I(2) = 67%). The significant reduction in the risk for diarrhea was lost in the random effects model (RR, 0.45; 95% CI, 0.11-1.75). Given the simple nature of the intervention, the scarcity of data is noteworthy. No consistent effect of yogurt consumption for preventing AAD was shown. However, the data are limited and the included trials had methodological limitations. Results from large, rigorously designed RCTs are needed to assess the effect of yogurt consumption on AAD prevention. Copyright © 2015 Elsevier Inc. All rights reserved.

Healthy yogurt fortified with n-3 fatty acids from vegetable sources.

PubMed

Dal Bello, B; Torri, L; Piochi, M; Zeppa, G

2015-12-01

The concentration of n-3 polyunsaturated fatty acids (PUFA) in yogurt was increased using 5 different vegetable oils obtained from flaxseed, Camelina sativa, raspberry, blackcurrant, and Echium plantagineum. The vegetable oils were added to partially skim milk before lactic fermentation at a concentration adequate enough to cover at least 10% of the recommended daily intake of 2 g/d of α-linolenic acid according to EC regulation no. 432/2012. Microbiological (lactobacilli and streptococci, yeast, and molds), chemical (pH, syneresis, proximate composition, fatty acids, oxidation stability), and sensory evaluations were assessed for all of the fortified yogurts after 0, 7, 14, and 21 d of storage at 4°C. Sensory evaluations were conducted at 21 d of storage at 4°C. Among the yogurts produced, those that were supplemented with flaxseed and blackcurrant oils exhibited the highest α-linolenic acid content (more than 200mg/100 g of yogurt) at the end of storage. The addition of oil did not influence the growth of lactic acid bacteria that were higher than 10(7) cfu/g at 21 d of storage. All of the yogurts were accepted by consumers, except for those supplemented with raspberry and E. plantagineum oils due to the presence of off flavors. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Microencapsulated cells of Lactobacillus paracasei subsp. paracasei in biopolymer complex coacervates and their function in a yogurt matrix.

PubMed

Bosnea, L A; Moschakis, T; Biliaderis, C G

2017-02-22

L. paracasei subsp. paracasei E6 cells were encapsulated by complex coacervation using whey protein isolate (WPI) and gum arabic and introduced in stirred yogurts after fermentation. For comparison purposes, yogurts without addition of L. paracasei and yogurts with free cells of L. paracasei were produced. The survival of free and microencapsulated L. paracasei cells was evaluated during storage of the yogurts for 45 days at 4 °C. In addition, yogurts were exposed to simulated gastric juice and the reduction in viable numbers of L. paracasei cells was assessed. The effect of complex coacervates' addition on the rheological properties of yogurts was also evaluated. Yogurts containing encapsulated L. paracasei cells showed a slightly improved cell survival (≤0.22 log CFU g -1 reduction) during storage when compared to yogurts containing free cells (≤0.64 log CFU g -1 reduction). Moreover, the microencapsulated L. paracasei cells exhibited greater survival compared to free cells upon exposure of the yogurt samples to simulated gastric juice (pH 2.0) for 3 h. Finally, the incorporation of complex coacervates did not significantly affect the rheological properties of yogurts especially when added at concentrations less than 10% w/w. Consequently, the inclusion of microencapsulated bacteria by complex coacervation in yogurts, could become an effective vehicle for successful delivery of probiotics to the gut, and hence contributing to the improvement of the gastrointestinal tract health, without altering the texture of the product.

Effect of mixing during fermentation in yogurt manufacturing.

PubMed

Aguirre-Ezkauriatza, E J; Galarza-González, M G; Uribe-Bujanda, A I; Ríos-Licea, M; López-Pacheco, F; Hernández-Brenes, C M; Alvarez, M M

2008-12-01

In traditional yogurt manufacturing, the yogurt is not agitated during fermentation. However, stirring could be beneficial, particularly for improving heat and mass transport across the fermentation tank. In this contribution, we studied the effect of low-speed agitation during fermentation on process time, acidity profile, and microbial dynamics during yogurt fermentation in 2 laboratory-scale fermenters (3 and 5 L) with different heat-transfer characteristics. Lactobacillus bulgaricus and Streptococcus thermophilus were used as fermenting bacteria. Curves of pH, lactic acid concentration, lactose concentration, and bacterial population profiles during fermentation are presented for static and low-agitation conditions during fermentation. At low-inoculum conditions, agitation reduced the processing time by shortening the lag phase. However, mixing did not modify the duration or the shape of the pH profiles during the exponential phase. In fermentors with poor heat-transfer characteristics, important differences in microbial dynamics were observed between the agitated and nonagitated fermentation experiments; that is, agitation significantly increased the observable specific growth rate and the final microbial count of L. bulgaricus.

Habitual yogurt consumption and health-related quality of life: a prospective cohort study.

PubMed

Lopez-Garcia, Esther; Leon-Muñoz, Luz; Guallar-Castillon, Pilar; Rodríguez-Artalejo, Fernando

2015-01-01

Health-related quality of life (HRQL) is a global indicator of perceived health status, which includes physical and mental domains. Several biological mechanisms might support an association between consumption of yogurt and better HRQL. Our aim was to assess the association between habitual yogurt consumption and HRQL in the general adult population. We conducted a prospective study with 4,445 individuals aged 18 years and older who were recruited in 2008 to 2010 and were followed up to 2012. Habitual yogurt consumption was assessed at baseline with a validated diet history. HRQL was measured with the Physical Composite Summary and the Mental Composite Summary of the Spanish version of the SF-12 Health Survey. The analysis of the association between baseline yogurt consumption and HRQL at 2012 was performed with linear regression and adjusted for the main confounders, including baseline HRQL. Mean follow-up was 3.5 years (standard deviation=0.6 years). Compared with nonconsumers of yogurt, the Physical Composite Summary scores were similar in habitual consumers of ≤6 servings/week (β=.40; P=0.20) and in consumers of ≥1 serving/day (β=.25; P=0.45). A suggestion of tendency toward a lower Mental Composite Summary score was found among daily yogurt consumers (β=-.65; P=0.09; P for trend across categories=0.07). Results were similar among individuals without morbidity, never smokers, and individuals with higher adherence to the Mediterranean diet. Habitual yogurt consumption did not show an association with improved HRQL. Copyright © 2015 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

[Clinical effects of Lactobacillus acidophilus strain L-55-contained yogurt on symptoms of Japanese cedar pollen allergy].

PubMed

Kimura, Goro; Akagi, Hirofumi; Okada, Chiharu; Hirano, Atsushi; Amano, Yoshimi; Ohmura, Etsuko; Nakashige, Yoshito; Sunada, Yosuke; Fujii, Yusuke; Nakamura, Syoji; Soda, Ryo; Takahashi, Kiyoshi

2012-05-01

It has been reported that oral administration of Lactobacillus acidophilus strain L-55 (L-55) suppressed nasal symptom and antigen-specific IgE induced by antigen challenge in mice. We investigated clinical effects of L-55-contained yogurt on symptoms and IgE production in the patients with Japanese cedar pollinosis. The study was performed as a randomized double blind placebo-controlled trial. L-55-contained yogurt (L-55 yogurt) or placebo yogurt was started to administer to each subject from 4 weeks prior to the onset of Japanese cedar pollen release for total 13 weeks. The mean value of symptom score and symptom medication score were lower in L-55 yogurt group compared with placebo yogurt group during 5th week to 9th week from the first week of Japanese cedar pollination. Especially, in medicated subjects, total symptom score and throat symptom score were significantly lower in L-55 yogurt group compared with placebo yogurt group at 5th and 4th week from the first week of Japanese cedar pollination, respectively. Moreover, in medicated subjects, change ratio of serum total IgE was significantly lower in L-55 yogurt group compared with placebo yogurt group at 1st week from the first week of Japanese cedar pollination. Intake of L-55 during Japanese cedar pollinating season may be effective in alleviating the allergic symptoms related to Japanese cedar pollinosis. From these finding, it was suggested that L-55 is a possible candidate as a complementary medicine for Japanese cedar pollinosis.

Effect of Mandarin Orange Yogurt on Allergic Conjunctivitis Induced by Conjunctival Allergen Challenge.

PubMed

Hara, Yuko; Shiraishi, Atsushi; Sakane, Yuri; Takezawa, Yuki; Kamao, Tomoyuki; Ohashi, Yuichi; Yasunaga, Sho; Sugahara, Takuya

2017-06-01

To evaluate the effects of mandarin orange yogurt containing nobiletin and β-lactoglobulin on the allergic conjunctivitis induced by a conjunctival allergen challenge (CAC). Experiment 1 was performed on 26 asymptomatic patients (age, 25.3 ± 5.3 years) with proven seasonal allergic conjunctivitis due to cedar pollen. We compared the degree of conjunctivitis induced by CAC before and after ingesting mandarin orange yogurt for 2 weeks. Experiment 2 was a double-blind, placebo-controlled trial performed on 31 patients (age, 32.5 ± 12.2 years). A diet containing mandarin orange yogurt was compared to a diet containing yogurt lacking the mandarin orange on the conjunctivitis induced by CAC. The temperature of the inferior bulbar conjunctiva was measured before and 20 minutes after the CAC with an ocular surface thermographer (OST). The degree of conjunctival injection and chemosis was graded by slit-lamp biomicroscopy. The changes in the symptoms were evaluated by a questionnaire. In experiment 1, the scores of redness (3.07 ± 3.03 vs. 1.05 ± 1.70), chemosis (2.84 ± 2.27 vs. 0.81 ± 1.11), itching (4.34 ± 3.05 vs. 1.39 ± 2.12), and temperature (0.73 ± 0.42°C vs. 0.45 ± 0.43°C) were significantly lower (P < 0.001) after a diet of mandarin orange yogurt for 2 weeks. In experiment 2, the scores of redness (1.03 ± 0.18 vs. 1.28 ± 0.52; P = 0.0156), itching (1.93 ± 1.92 vs. 2.82 ± 2.21; P = 0.0133), and surface temperature (0.54 ± 0.21°C vs. 0.31 ± 0.25°C; P < 0.001) were significantly lower in the mandarin orange yogurt group than in the control yogurt group. Mandarin orange yogurt can be an effective nutritional intervention for allergic conjunctivitis.

Direct Application of Rep-PCR on Type I Sourdough Matrix to Monitor the Dominance and Persistence of a Lactobacillus plantarum Starter Throughout Back-Slopping.

PubMed

Dolci, Paola; Cocolin, Luca

2017-08-01

This study describes the optimization and application of repetitive element-PCR (rep-PCR) technique directly on microbial DNA extracted from type I sourdoughs for fast monitoring of a Lb. plantarum starter strain (P1FMC) throughout daily back-slopping. The challenge was to follow and study the performance of a starter culture directly in sourdoughs without cultivation on selective media. The extraction of good quality microbial DNA suitable for amplification from a complex matrix such as dough was the first target. In addition, the objective to obtain a clear rep-PCR profile referable to a specific starter strain among a microbial community was pursued. Co-inoculum trials, in flour matrix, with Lb. plantarum P1FMC and L. lactis LC71 strains and, subsequently, type I sourdough back-slopping trials were performed. The rep-PCR amplification profiles obtained were clearly referable to that of Lb. plantarum P1FMC starter in both co-inoculum trials (also when it was present with one order of magnitude less with respect to L. lactis LC71) and back-slopping trials where it dominated the fermentation process with loads of 10 8 cfu g -1 and prevailed on the autochthonous microbiota. Thus, the approach proposed in this paper could be considered a methodological advancement, based on a culture-independent one-step rep-PCR, suitable for fast monitoring of starter performance. © 2017 Institute of Food Technologists®.

Effect of dried nut fortification on functional, physicochemical, textural, and microbiological properties of yogurt.

PubMed

Ozturkoglu-Budak, S; Akal, C; Yetisemiyen, A

2016-11-01

In this study, walnut, hazelnut, almond, or pistachio were incorporated to produce functional yogurts. The effects on physicochemical and instrumental textural characteristics and syneresis, contents of folic acid, selenium, tocopherols, and n-3 and n-6 (omega) fatty acids, and viable counts of Streptococcus thermophilus and Lactobacillus bulgaricus were evaluated during storage. Fortified yogurts demonstrated higher protein and total solid contents and lower syneresis compared with control yogurt on d 21. Addition of nuts, except walnut, also increased S. thermophilus and L. bulgaricus counts. The concentrations of folic acid, α-tocopherol, selenium, and n-3 and n-6 fatty acids were higher in fortified yogurts compared with the levels found in the respective nut types. However, a decreasing trend was observed in all components during storage. Consequently, each nut could be incorporated into yogurt because of a specific functional property. For instance, walnut could be preferred for omega acid enrichment. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of oxidoreduction potential on aroma biosynthesis by lactic acid bacteria in nonfat yogurt.

PubMed

Martin, F; Cachon, R; Pernin, K; De Coninck, J; Gervais, P; Guichard, E; Cayot, N

2011-02-01

The aim of this study was to investigate the effect of oxidoreduction potential (Eh) on the biosynthesis of aroma compounds by lactic acid bacteria in non-fat yogurt. The study was done with yogurts fermented by Lactobacillus bulgaricus and Streptococcus thermophilus. The Eh was modified by the application of different gaseous conditions (air, nitrogen, and nitrogen/hydrogen). Acetaldehyde, dimethyl sulfide, diacetyl, and pentane-2,3-dione, as the major endogenous odorant compounds of yogurt, were chosen as tracers for the biosynthesis of aroma compounds by lactic acid bacteria. Oxidative conditions favored the production of acetaldehyde, dimethyl sulfide, and diketones (diacetyl and pentane-2,3-dione). The Eh of the medium influences aroma production in yogurt by modifying the metabolic pathways of Lb. bulgaricus and Strep. thermophilus. The use of Eh as a control parameter during yogurt production could permit the control of aroma formation. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A resistant-starch enriched yogurt: fermentability, sensory characteristics, and a pilot study in children

PubMed Central

Aryana, Kayanush; Greenway, Frank; Dhurandhar, Nikhil; Tulley, Richard; Finley, John; Keenan, Michael; Martin, Roy; Pelkman, Christine; Olson, Douglas; Zheng, Jolene

2015-01-01

The rising prevalence of obesity and the vulnerability of the pediatric age group have highlighted the critical need for a careful consideration of effective, safe, remedial and preventive dietary interventions.  Amylose starch (RS2) from high-amylose maize (HAM) ferments in the gut and affects body weight.   One hundred and ten children, of 7-8 (n=91) or 13-14 (n=19) years of age scored the sensory qualities of a yogurt supplemented with either HAM-RS2 or an amylopectin starch.  The amylopectin starch yogurt was preferred to the HAM-RS2-enriched yogurt by 7-8 year old panelists ( P<0.0001).  Appearance, taste, and sandiness scores given by 13- to 14-year-old panelists were more favorable for the amylopectin starch yogurt than for HAM-RS2-enriched yogurt ( P<0.05).  HAM-RS2 supplementation resulted in acceptable (≥6 on a 1-9 scale) sensory and hedonic ratings of the yogurt in 74% of subjects.  Four children consumed a HAM-RS2-enriched yogurt for four weeks to test its fermentability in a clinical trial.  Three adolescents, but not the single pre-pubertal child, had reduced stool pH ( P=0.1) and increased stool short-chain fatty acids (SCFAs) ( P<0.05) including increased fecal acetate ( P=0.02), and butyrate ( P=0.089) from resistant starch (RS) fermentation and isobutyrate ( P=0.01) from protein fermentation post-treatment suggesting a favorable change to the gut microbiota.  HAM-RS2 was not modified by pasteurization of the yogurt, and may be a palatable way to increase fiber intake and stimulate colonic fermentation in adolescents.  Future studies are planned to determine the concentration of HAM-RS2 that offers the optimal safe and effective strategy to prevent excessive fat gain in children. PMID:26925221

Relevance of the Mention of Antioxidant Properties in Yogurt Labels: In Vitro Evaluation and Chromatographic Analysis

PubMed Central

Pereira, Eliana; Barros, Lillian; Ferreira, Isabel C. F. R.

2013-01-01

The purpose of the inclusion of fruit (natural additives) in yogurt aims to increase its antioxidant activity and functionality. Herein, a comparative study of the antioxidant potential of yogurts with pieces of various fruits was performed, including yogurts with mention of antioxidant properties in the label. Free radicals scavenging activity, reducing power and inhibition of lipid peroxidation were evaluated by in vitro assays, as were the contents in antioxidants such as phenolics, flavonoids, sugars and tocopherols. After analyzing thirteen yogurts containing fruit pieces and a natural one (control), the most interesting were yogurts with pieces of berries (for phenolics, flavonoids and 2,2-dipheny-1-picrylhydrazyl (DPPH) scavenging activity), pineapple (for reducing power), blackberry (for β-carotene bleaching inhibition), blackberry “antioxidant” (for tocopherols) and cherry (for sugars). The mention of “antioxidant” in the label was relevant for tocopherols, sugars, DPPH scavenging activity and reducing power. No synergisms were observed in yogurts prepared with pieces of different fruits. Nevertheless, the addition of fruit pieces to yogurt was favorable for antioxidant content, increasing the protection of the consumer against diseases related to oxidative stress. PMID:26787624

Toxicological assessment of Penicillium nalgiovense strains for use as starter cultures in the manufacture of dry fermented sausages.

PubMed

Ludemann, Vanesa; Pose, Graciela; Moavro, Alfonsina; Maliaviabarrena, Maria G; Fandiño, Rosario; Ripoll, Giselle; Basílico, Juan C; Pardo, Alejandro G

2009-08-01

The use of fungal starter strains in the casing of dry fermented sausages allows standardization of the manufacturing process and ensures consumer safety. Penicillium nalgiovense is normally used for this purpose. Even though this species is reported as safe with respect to the production of the most common mycotoxins, its safety may be strain specific. The aim of the present work was to assess the toxicogenic potential of nine P. nalgiovense strains isolated from dry fermented sausages that were previously suitable as starters. The strains were tested for toxicity on brine shrimp larvae and the human cell line MCF7, for mutagenicity in the Ames test, and for antibacterial activity against gram-positive and gram-negative bacteria. According to our results, several P. nalgiovense strains were positive in more than one bioassay. Therefore, it is important to use different toxicological assays when characterizing strains intended for food use. Strains S1-2 and S14-4, which belong to biotypes 6 and 5, respectively, were nontoxigenic under the conditions tested. Overall, strain S1-2 of P. nalgiovense proved to be best suited as a starter in dry fermented sausage manufacture because in addition of being nontoxicogenic it produces white conidia, which is a desirable feature.

Cupuassu (Theobroma grandiflorum) pulp, probiotic, and prebiotic: Influence on color, apparent viscosity, and texture of goat milk yogurts.

PubMed

Costa, Marion P; Frasao, Beatriz S; Silva, Adriana Cristina O; Freitas, Mônica Q; Franco, Robson M; Conte-Junior, Carlos A

2015-09-01

Cupuassu is an acidic fruit that has a characteristic aroma, flavor, and texture; its fiber-rich pulp can provide a different consistency than other fruit pulps. Goat milk is an excellent source of amino acids, fatty acids, and minerals, and is widely used for processing fermented milks, such as yogurt. However, compared with cow milk yogurts, it is difficult to make goat milk yogurts with a good consistency. Therefore, it is necessary to use certain technological strategies. This study was carried out to investigate the possibility of adding cupuassu pulp, probiotic (Lactobacillus acidophilus LA-5), and prebiotic (inulin) to improve the texture of goat milk yogurt. A total of 6 treatments were performed: natural (N), probiotic (Pro), prebiotic (Pre), synbiotic (S), cupuassu (C), and probiotic with cupuassu (PC). The viability of probiotic in yogurts (Pro, S, and PC) was evaluated. In addition, instrumental analyses (pH, color, apparent viscosity, and texture) were performed to evaluate the influence of these different ingredients on goat milk yogurts. The probiotic bacteria remained viable (≥7 log cfu·mL(-1)) throughout the 28d of refrigerated storage, which exceeded the minimum count required to confer probiotic physiological benefits. The pH levels of the yogurts inoculated with L. acidophilus (Pro, S, and PC) were lower than others yogurts (N, Pre, and C). However, all yogurt samples underwent gradual decreases in pH until 7 to 14d of storage. The lightness (L*) was affected initially by addition of all ingredients (cupuassu pulp, probiotic, and prebiotic). The addition of cupuassu pulp (C and PC) increased the L* during the period of storage. Apparent viscosity and firmness decreased in the PC yogurt. The consistency was highest in the yogurts with added prebiotic (Pre and S) than the other yogurts (N, Pro, C, and PC) at the end of the storage period (d 28). The cohesiveness remained constant in all yogurts (N, Pro, Pre, S, C, and PC). Based on the results

Influence of yogurt fermentation and refrigerated storage on the stability of protein toxin contaminants.

PubMed

Jackson, Lauren S; Triplett, Odbert A; Tolleson, William H

2015-06-01

Dairy products sold in a ready-to-eat form present the risk that adulterants persisting through manufacturing, storage, and distribution would reach consumers. Pathogenic microbes, including shigatoxigenic strains of Escherichia coli and the toxins they produce, are common food safety hazards associated with dairy products. Ricin and abrin are plant-derived ribosome-inactivating protein toxins related to the shiga-like toxins produced by E. coli. Limited information exists on the effects of manufacturing processes on the stabilities of these heat-resistant ribosome-inactivating proteins in the presence of foods. The goal of this study was to determine how typical yogurt manufacturing and storage processes influence ribosome-inactivating protein toxins. Ricin and abrin were added to skim or whole milk and batch pasteurized. Complete inactivation of both toxins was observed after 30 minutes at 85 °C. If the toxins were added after pasteurization, the levels of ricin and abrin in yogurt and their cytotoxic activities did not change significantly during fermentation or refrigerated storage for 4 weeks. The activities of ricin and abrin were inhibited by skim milk, nonfat yogurt, whole milk, and whole milk yogurt. The results showed minimal effects of the toxins on yogurt pH and %titratable acidity but inhibitory effects of yogurt on toxin activity. Published by Elsevier Ltd.

Fast real-time polymerase chain reaction for quantitative detection of Lactobacillus delbrueckii bacteriophages in milk.

PubMed

Martín, Maria Cruz; del Rio, Beatriz; Martínez, Noelia; Magadán, Alfonso H; Alvarez, Miguel A

2008-12-01

One of the main microbiological problems of the dairy industry is the susceptibility of starter bacteria to virus infections. Lactobacillus delbrueckii, a component of thermophilic starter cultures used in the manufacture of several fermented dairy products, including yogurt, is also sensitive to bacteriophage attacks. To avoid the problems associated with these viruses, quick and sensitive detection methods are necessary. In the present study, a fast real-time quantitative polymerase chain reaction assay for the direct detection and quantification of L. delbrueckii phages in milk was developed. A set of primers and a TaqMan MGB probe was designed, based on the lysin gene sequence of different L. delbrueckii phages. The results show the proposed method to be a rapid (total processing time 30 min), specific and highly sensitive technique for detecting L. delbrueckii phages in milk.

Exploring Milk and Yogurt Selection in an Urban Universal School Breakfast Program

ERIC Educational Resources Information Center

Miller, M. Elizabeth; Kwon, Sockju

2015-01-01

Purpose/Objectives: The purpose of this study was to explore milk and yogurt selection among students participating in a School Breakfast Program. Methods: Researchers observed breakfast selection of milk, juice and yogurt in six elementary and four secondary schools. Data were analyzed using descriptive statistics and logistic regression to…

Antioxidant activity and protein-polyphenol interactions in a pomegranate (Punica granatum L.) yogurt.

PubMed

Trigueros, Lorena; Wojdyło, Aneta; Sendra, Esther

2014-07-09

Pomegranate juice (PGJ) is rich in phenolics which are potent antioxidants but also prone to interact with proteins. A yogurt rich in PGJ (40%) made from arils was elaborated (PGY) to determine the antioxidant activity and to estimate the phenolics-proteins interaction during 28 days of cold storage. Juice, yogurts, and protein-free permeates were analyzed for phenolic composition. Yogurt fermentation modified the anthocyanin profile of the initial PGJ, especially the content in cyanidin-3-O-glucoside. During storage, individual anthocyanin content in PGY decreased but it did not modify yogurt color. The analysis of permeates revealed that the degree of phenol-protein interaction depends on the type of phenolic, ellagic acid and dephinidin-3,5-O-diglucoside being the least bound phenolic compounds. The presence of PGJ in yogurt enhanced radical scavenging performance, whereas all the observed ferric reducing power ability of PGY was strictly due to the PGJ present. The 84.73% of total anthocyanins remained bound to proteins at the first day of storage and 90.06% after 28 days of cold storage, revealing the high affinity of anthocyanins for milk proteins.

Immune Regulatory Effect of Newly Isolated Lactobacillus delbrueckii from Indian Traditional Yogurt.

PubMed

Hong, Yi-Fan; Lee, Yoon-Doo; Park, Jae-Yeon; Jeon, Boram; Jagdish, Deepa; Jang, Soojin; Chung, Dae Kyun; Kim, Hangeun

2015-08-01

Lactic acid bacteria (LAB) are microorganisms that are believed to provide health benefits. Here, we isolated LAB from Indian fermented foods, such as traditional Yogurt and Dosa. LAB from Yogurt most significantly induced TNF-α and IL-1β production, whereas LAB from Dosa induced mild cytokine production. After 16S rRNA gene sequencing and phylogenetic analysis, a Yogurt-borne lactic acid bacterium was identified and classified as Lactobacillus delbrueckii subsp. bulgaricus, and it was renamed L. delbrueckii K552 for the further studies. Our data suggest that the newly isolated L. delbrueckii can be used for the treatment of immune deficiency disorders.

Improving characteristics of goat milk yogurt drink fortified by mangosteen rind (Garcinia mangostana Lin.) extract

NASA Astrophysics Data System (ADS)

Wibawanti, J. M. W.; Rinawidiastuti; Arifin, H. D.; Zulfanita

2018-01-01

Peranakan Etawah (PE) milk is highly nutritive goaty flavour make it not preferable by consumer. Processing of yogurt drink made PE goat milk enhances palatability. Goat yogurt drink can be supplemented high antioxidantive activity by mangosteen rind extract. Comletely Randomized Design (CRD) was throughout the research with different concentrations of mangosteen rind extract (0, 1, 2, 3, and 4% (v/v). The organoleptic analysis showed the significant enhancement by fortification with mangosteen rind extract. The highest antioxidant activity was shown on the yogurt drink 4% v/v of mangosteen extract. In conclusion, the fortification of mangosteen rind extract was enhanced of characteristics of yogurt drink.

Physiological and anthropometric characteristics of starters and non-starters and playing positions in elite Australian Rules Football: a case study.

PubMed

Young, W B; Newton, R U; Doyle, T L A; Chapman, D; Cormack, S; Stewart, G; Dawson, B

2005-09-01

A purpose of this study was to determine if pre-season anthropometric and physiological measures were significantly different for the players from one Australian Football League (AFL) club selected to play in the first game of the season compared to the players not selected. Another purpose was to compare fitness test results for defenders, forwards and mid-fielders in the same AFL club. Thirty-four players were tested for isolated quadriceps and hamstrings strength, leg extensor muscle strength and power, upper body strength, sprinting speed, vertical jump (VJ), endurance, skinfolds and hamstring flexibility. The starters who were selected to play the first game were a significantly older and more experienced playing group, and were significantly better (p < 0.05) in measures of leg power, sprinting speed and the distance covered in the Yo Yo intermittent recovery test compared to the non-starters. Although there were trends for the superiority of the starters, the differences in lower and upper body strength, VJ and predicted VO2max were non-significant. The forwards generally produced the worst fitness scores of the playing positions with the midfielders having significantly lower skinfolds and the defenders possessing better hamstring strength and VJ compared to the forwards. It was concluded that some fitness qualities can differentiate between starters and non-starters, at least in one AFL club. Comparisons of playing positions and the development of fitness norms for AFL players require further research.

A systematic review of the effect of yogurt consumption on chronic diseases risk markers in adults.

PubMed

Dumas, Audrée-Anne; Lapointe, Annie; Dugrenier, Marilyn; Provencher, Véronique; Lamarche, Benoît; Desroches, Sophie

2017-06-01

We reviewed randomised controlled trials (RCTs) that have assessed the effects of yogurt containing Lactobacillus bulgaricus and Streptococcus thermophilus (LBST) on metabolic risk markers of chronic diseases in adults. We performed a systematic search in July 2016 in the scientific databases PubMed, EMBASE and The Cochrane Library. Included studies were RCTs that assessed the impact of consuming yogurt containing LBST as a treatment, and that evaluated at least one metabolic risk marker for chronic diseases compared with a control diet or a diet supplemented in another food/ingredient in healthy or chronically ill adults. Seven RCTs involving 278 participants were included in the review. Studies were conducted in the USA, France, Spain, Iran and Canada. Five studies were undertaken in healthy adults, and two were conducted among lactose malabsorbers. All studies investigated changes in blood lipids and glucose homoeostasis, with different doses of yogurt, durations of the supplementation and risks markers assessed. Consumption of LBST yogurt significantly reduced total cholesterol concentrations, ratio of total cholesterol to HDL-C and plasma glucose compared to a control yogurt-free diet or diet supplemented in another food/ingredient in two out of the seven studies. The majority of included RCTs presented high to unclear methodological risks of bias, which raises questions about the validity of their findings. Data from this systematic review indicate that the consumption of LBST yogurt shows either favourable or neutral effects on metabolic risk markers when compared with a control treatment in controlled research settings. RCTs investigating the effect of LBST yogurt consumption on metabolic risk markers of chronic diseases are scarce and presented considerable variation in methodologies making comparison between studies difficult. Further large-scale, well-designed studies assessing the impact of LBST yogurt, in particular in comparison with a control yogurt

Association between yogurt consumption and the risk of metabolic syndrome over 6 years in the SUN study.

PubMed

Sayón-Orea, Carmen; Bes-Rastrollo, Maira; Martí, Amelia; Pimenta, Adriano M; Martín-Calvo, Nerea; Martínez-González, Miguel A

2015-02-21

The role of yogurt consumption in the development of metabolic syndrome (MetS) is not fully understood and the available epidemiologic evidence is scarce. The aim of our study was to assess the association between total, whole-fat, or low-fat yogurt consumption and the risk of developing MetS. Yogurt consumption was assessed at baseline through a 136-item validated FFQ. MetS was defined following the harmonized definition for MetS according to the AHA and the IDF criteria. Logistic regression models were used. During the first 6-y of follow-up of the SUN cohort, 306 incident cases of MetS were identified. Frequent consumption [≥875 g/week (≥7 servings/week) versus ≤ 250 g/week (2 servings/week)] of total, whole-fat and low-fat yogurt consumption showed non-significant inverse associations with MetS [OR = 0.84 (95% CI: 0.60-1.18); 0.98 (95% CI: 0.68-1.41); and 0.63 (95% CI: 0.39-1.02) respectively]. Only one component of the MetS, central adiposity, was inversely associated with total and whole-fat yogurt consumption [OR = 0.85 (95% CI: 0.74-0.98) and 0.85 (95% CI: 0.73-0.99) respectively]. In the joint assessment of exposure to total yogurt consumption and fruit consumption, those in the highest category of total yogurt consumption, and having a high fruit consumption (above the median ≥264.5 g/day) exhibited a significantly lower risk of developing MetS [OR = 0.61 (95% CI: 0.38-0.99)] compared with those in the lowest category of total yogurt consumption and had fruit consumption below the study median. No significant association between yogurt consumption and MetS was apparent. Only one component out of the 5 MetS criteria, central adiposity, was inversely associated with high yogurt consumption. The combination of high consumption of both yogurt and fruit was inversely associated with the development of MetS.

Consumer perception, health information, and instrumental parameters of cupuassu (Theobroma grandiflorum) goat milk yogurts.

PubMed

Costa, Marion P; Monteiro, Maria Lucia G; Frasao, Beatriz S; Silva, Vitor L M; Rodrigues, Bruna L; Chiappini, Claudete C J; Conte-Junior, Carlos A

2017-01-01

Although the demand for goat milk products has been growing, they have lower consumer acceptability than products derived from cow milk. However, the addition of cupuassu pulp can be used to improve the formulation of these products. For this reason, the aim of this study was to investigate the influence of new goat milk yogurt manufactured with cupuassu pulp on physicochemical properties, consumers' perceptions, and overall consumer acceptance. In addition, the effect of antioxidant health information on consumer acceptance and purchase intention of cupuassu goat milk yogurts was evaluated. The results demonstrated a positive expectation regarding linking and familiarity to goat milk products and products with cupuassu pulp. The pH, total phenolic content, lightness, redness, yellowness, and apparent viscosity were potentially affected by the addition of cupuassu, with the highest concentration of cupuassu (10%) exhibiting the greatest changes in parameters. Based on principal component analysis, partial least squares regression, and just-about-right and penalty analysis, the addition of cupuassu pulp improved some sensory attributes of goat milk yogurt, such as cupuassu aroma, cupuassu flavor, yellow color, consistency, and viscosity, which positively influenced product acceptance. In addition, antioxidant health information increased the acceptance and purchase intention of cupuassu goat milk yogurts. Taking into account the parameters investigated in this study, the best scoring formulation was goat milk yogurt with 10% cupuassu pulp. Our results suggest that cupuassu pulp can be considered a potential ingredient to improve the sensory and texture properties of goat milk yogurt. Furthermore, the antioxidant health information could be a sensory strategy to increase the acceptance of cupuassu goat milk yogurts. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

The Potential Role of Yogurt in Weight Management and Prevention of Type 2 Diabetes.

PubMed

Panahi, Shirin; Tremblay, Angelo

2016-01-01

Yogurt is a semisolid fermented milk product that originated centuries ago and is viewed as an essential food and important source of nutrients in the diet of humans. Over the last 30 years, overweight and obesity have become characteristic of Western and developing countries, which has led to deleterious health outcomes, including cardiovascular disease, type 2 diabetes, hypertension, and other chronic conditions. Recent epidemiological and clinical evidence suggests that yogurt is involved in the control of body weight and energy homeostasis and may play a role in reducing the risk for type 2 diabetes partly via the replacement of less healthy foods in the diet, its food matrix, the effect of specific nutrients such as calcium and protein on appetite control and glycemia, and alteration in gut microbiota. This review will discuss the specific properties that make yogurt a unique food among the dairy products, epidemiological and clinical evidence supporting yogurt's role in body weight, energy balance, and type 2 diabetes, including its potential mechanisms of action and gaps that need to be explored. Key teaching points • Several epidemiological and clinical studies have suggested a beneficial effect of yogurt consumption in the control of body weight and energy homeostasis, although this remains controversial. • Yogurt possesses unique properties, including its nutritional composition; lactic acid bacteria, which may affect gut microbiota; and food matrix, which may have a potential role in appetite and glycemic control. • Potential mechanisms of action of yogurt include an increase in body fat loss, decrease in food intake and increase in satiety, decrease in glycemic and insulin response, altered gut hormone response, replacement of less healthy foods, and altered gut microbiota. • The relative energy and nutrient content and contribution of a standard portion of yogurt to the overall diet suggest that the percentage daily intake of these nutrients

Yogurt consumption is associated with better diet quality and metabolic profile in American men and women

PubMed Central

Wang, Huifen; Livingston, Kara A.; Fox, Caroline S.; Meigs, James B.; Jacques, Paul F.

2013-01-01

The evidence-based Dietary Guidelines for Americans recommends increasing the intake of fat-free or low-fat milk and milk products. However, yogurt, a nutrient-dense milk product, has been understudied. This cross-sectional study examined whether yogurt consumption was associated with better diet quality and metabolic profile among adults (n = 6526) participating in the Framingham Heart Study Offspring (1998-2001) and Third Generation (2002-2005) cohorts. A validated food frequency questionnaire was used to assess dietary intake, and the Dietary Guidelines Adherence Index (DGAI) was used to measure overall diet quality. Standardized clinical examinations and laboratory tests were conducted. Generalized estimating equations examined the associations of yogurt consumption with diet quality and levels of metabolic factors. Approximately 64% of women (vs 41% of men) were yogurt consumers (ie, consumed >0 servings/week). Yogurt consumers had a higher DGAI score (ie, better diet quality) than nonconsumers. Adjusted for demographic and lifestyle factors and DGAI, yogurt consumers, compared with nonconsumers, had higher potassium intakes (difference, 0.12 g/d) and were 47%, 55%, 48%, 38%, and 34% less likely to have inadequate intakes (based on Dietary Reference Intake) of vitamins B2 and B12, calcium, magnesium, and zinc, respectively (all P ≤ .001). In addition, yogurt consumption was associated with lower levels of circulating triglycerides, glucose, and lower systolic blood pressure and insulin resistance (all P < .05). Yogurt is a good source of several micronutrients and may help to improve diet quality and maintain metabolic well-being as part of a healthy, energy-balanced dietary pattern. PMID:23351406

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�

Effect of Fruit Lemon Juice Addition to The Content of Protein, Fat, Lactose and Probiotic on Soy Yogurt

NASA Astrophysics Data System (ADS)

Supriyanti, F. M. T.; Zackiyah; Azizah, N.

2017-02-01

This research aimed to determine the effect of lemon juice to the content of protein, fat, lactose and probiotics, in beverages soy yogurt. Soy yogurt which produced was a multifunction yogurt drink high levels of antioxidants, contains probiotics and can be used by people with lactose intolerance. The research method includes the production of fortified soy yogurt with lemon juice, were made with the ratio between the lemon juice and soy yogurt were 0:10 (L0); 1:9 (L1); 2:8 (L2); and 3:7 (L3). Analysis of the results include the content of protein by Kjeldahl method, the content of fat by Soxhletasi method, lactose test by Luff Schoorls method and content of probiotics with total plate count enumeration techniques. The results showed fortified yogurt had a protein content greater than before fortification (L3 > L2 > L1 > L0); The fat content L0 > L1 > L2 > L3. Fortified yogurt lactose content is smaller than before fortification (L0 > L1 > L2 > L3). The content of probiotic yogurt fortified L1 > L3 > L2. From this research can be concluded that the yoghurt fortified (L3) is the best, with the highest protein content, low fat, low lactose than L1 and L2, and had probiotics content. It is advised to conduct further research on the expired time of fortified soy yogurt products

Yogurt consumption, weight change and risk of overweight/obesity: the SUN cohort study.

PubMed

Martinez-Gonzalez, M A; Sayon-Orea, C; Ruiz-Canela, M; de la Fuente, C; Gea, A; Bes-Rastrollo, M

2014-11-01

Epidemiological studies on the association between yogurt consumption and the risk of overweight/obesity are scarce. We prospectively examined the association of yogurt consumption with overweight/obesity and average annual weight gain. Prospective cohort study of 8516 men and women (mean age 37.1, SD: 10.8 y). Participants were followed-up every two years. Participants were classified in 5 categories of yogurt consumption at baseline: 0-2, >2-<5, 5-<7, 7 and ≥ 7 servings/week. Outcomes were: 1) average yearly weight change during follow-up; and 2) incidence of overweight/obesity. Linear regression models and Cox models were used to adjust for potential confounders. After a median follow-up of 6.6 years, 1860 incident cases of overweight/obesity were identified. A high (>7 servings/week) consumption of total and whole-fat yogurt was associated with lower incidence of overweight/obesity [multivariable adjusted hazard ratios = 0.80 (95% CI: 0.68-0.94); and 0.62 (0.47-0.82) respectively] in comparison with low consumption (0-2 servings/week). This inverse association was stronger among participants with higher fruit consumption. In this Mediterranean cohort, yogurt consumption was inversely associated with the incidence of overweight/obesity, especially among participants with higher fruit consumption. Copyright © 2014 Elsevier B.V. All rights reserved.

Genotyping by randomly amplified polymorphic DNA of bacteriocin producing Lactobacillus acidophilus strains from Nigeria.

PubMed

Alli, John Adeolu; Iwalokun, Bamidele A; Oluwadun, Afolabi; Okonko, Iheanyi Omezuruike

2015-01-01

Yogurt and starter culture producers are still searching strains of Lactobacillus acidophilus to produce healthier yogurt with a longer shelf life and better texture, taste, and quality. This study determined the genotyping of bacteriocin producing Lactobacillus acidophilus strains recovered from Nigerian yogurts. Yogurt samples were collected from four different states of South West regions of Nigeria. Isolates were obtained from MRS Medium and biochemically characterized. This was further confirmed by API50CH. The bacteriocin positivity and activity was determined. Genomic characterization of our Lactobacillus acidophilus strains was done with randomly amplified polymorphic DNA-PCR. All yogurt samples containing Lactobacillus acidophilus strains meet the probiotic requirement of ≥10(6) cfu/mL. The gel picture revealed 6 RAPD clonal types of Lactobacillus acidophilus strains with RAPD type C observed to be more common. Significant differences existed in the mean growth inhibition zone (t = -7.32, P < 0.05 for E. coli ATCC; t = -6.19, P < 0.05 for E. coli clinical isolates; t = -6.16, P < 0.05 for Enterobacter sp; t = -11.92, P < 0.05 for Salmonella typhi, t = -1.10, P > 0.05 Staphylococcus aureus). No correlation between the bacteriocin production, activity, and their RAPD clonal division (X(2) = 7.49, P = 0.1610, df = 5). In conclusion, L. acidophilus isolated in Nigeria samples met the probiotic requirements of ≥10(6) cfu/mL and produce bacteriocins with good spectrum of activity.

The associations between yogurt consumption, diet quality, and metabolic profiles in children in the USA.

PubMed

Zhu, Yong; Wang, Huifen; Hollis, James H; Jacques, Paul F

2015-06-01

Recent studies have shown that yogurt consumption was associated with better diet quality and a healthier metabolic profile in adults. However, such associations have not been investigated in children. The present study examined the associations in children using data from a nationally representative survey. Data from 5,124 children aged 2-18 years, who participated in the National Health and Nutrition Examination Survey (NHANES) between 2003 and 2006 in the USA were analyzed. The frequency of yogurt consumption over 12 months was determined using a validated food frequency questionnaire. Diet quality was assessed by the Healthy Eating Index 2005 (HEI-2005) using one 24-HR dietary recall, and metabolic profiles were obtained from the NHANES laboratory data. It was found that only 33.1 % of children consumed yogurt at least once per week (frequent consumers). Adjusting for covariates, frequent consumers had better diet quality than infrequent consumers, as indicated by a higher HEI-2005 total score (P = 0.04). Frequent yogurt consumption was associated with a lower fasting insulin level (P < 0.001), a lower homeostatic model assessment of insulin resistance (P < 0.001), and a higher quantitative insulin sensitivity check index (P = 0.03). However, yogurt consumption was not associated with body weight, fasting glucose, serum lipid profiles, C-reactive protein, and blood pressures (all P > 0.05). These results suggest that frequent yogurt consumption may contribute to improved diet quality and a healthier insulin profile in children. Future longitudinal studies and clinical trials in children are warranted to explore the health benefits of yogurt consumption.

Oleuropein as a bioactive constituent added in milk and yogurt.

PubMed

Zoidou, Evangelia; Magiatis, Prokopios; Melliou, Eleni; Constantinou, Maria; Haroutounian, Serkos; Skaltsounis, Alexios-Leandros