Starter Culture Activity in Refrigerated Fermented Soymilk

1999 ◽  
Vol 62 (7) ◽  
pp. 808-810 ◽  
Author(s):  
MARISA S. GARRO ◽  
GRACIELA F. de VALDEZ ◽  
GUILLERMO OLIVER ◽  
GRACIELA S. de GIORI

The refrigerated shelf life of soymilk fermented with single cultures of Lactobacillus fermentum, L. casei, Streptococcus salivarius subsp. thermophilus, and Bifidobacterium longum was evaluated. During storage at 4°C for 28 days, the stability of the microflora differed markedly among the starter cultures. After 28 days, the average numbers of S. salivarius subsp. thermophilus decreased by two log cycles to 6.0 × 107 CFU/ml, whereas those of L. casei increased gradually by more than two log cycles to 4.6 × 109 CFU/ml. Numbers of B. longum and L. fermentum remained moderately high (8.7 × 108 CFU/ml and 3.7 × 108 CFU/ml, respectively) even after 28 days of storage. S. salivarius subsp. thermophilus and L. casei continued to metabolize sucrose during the storage period, but the pattern of consumption was different among the strains. The other starter cultures did not seem to have significant activity (P > 0.05) on the residual sugars. In most cases, L(+)-lactate predominated.

2015 ◽  
Vol 6 (3) ◽  
pp. 381-386 ◽  
Author(s):  
A. Jofré ◽  
T. Aymerich ◽  
M. Garriga

The production of long shelf-life highly concentrated dried probiotic/starter cultures is of paramount importance for the food industry. The aim of the present study was to evaluate the protective effect of glucose, lactose, trehalose, and skim milk applied alone or combined upon the survival of potentially probiotic Lactobacillus rhamnosus CTC1679, Lactobacillus casei/paracasei CTC1677 and L. casei/paracasei CTC1678 during freeze-drying and after 39 weeks of storage at 4 and 22 °C. Immediately after freeze-drying, the percentage of survivors was very high (≥94%) and only slight differences were observed among strains and cryoprotectants. In contrast, during storage, survival in the dried state depended on the cryoprotectant, temperature and strain. For all the protectants assayed, the stability of the cultures was remarkably higher when stored under refrigeration (4 °C). Under these conditions, skim milk alone or supplemented with trehalose or lactose showed the best performance (reductions ≤0.9 log units after 39 weeks of storage). The lowest survival was observed during non-refrigerated storage and with glucose and glucose plus milk; no viable cells left at the end of the storage period. Thus, freeze-drying in the presence of appropriate cryoprotectants allows the production of long shelf-life highly concentrated dried cultures ready for incorporation in high numbers into food products as starter/potential probiotic cultures.


Foods ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1165 ◽  
Author(s):  
Mansi Limbad ◽  
Noemi Gutierrez Maddox ◽  
Nazimah Hamid ◽  
Kevin Kantono

There is a recognized need for formulating functional food products using selected lactic acid bacteria (LAB) starter cultures from various sources such as kefir, yoghurt or kombucha that have health benefits. The principle objective of this study was to investigate the use of a coconut water kefir-based fermentation starter culture using Lactobacillus fermentum and Lactobacillus plantarum to develop a sourdough bread. Check-all-that-apply (CATA) sensory profiling was used in this study to evaluate the sensory profile of sourdough breads that varied with culture type, culture concentrations, with and without added yeast, and with fermentation for 18 and 24 h. Based on correspondence analysis (CA) of the CATA results, bread samples with positive sensory attributes were chosen for further physicochemical analysis. Physicochemical analyses (texture, proximate composition, shelf life, carboxylic acid analysis and amino acid analysis) were carried out on breads formulated with starter culture concentrations of 8.30 log CFU/mL of L. fermentum, 4.90 log CFU/mL of L. fermentum and 9.60 log CFU/mL of L. plantarum, each fermented for 24 h without baker’s yeast. The bread sample that was formulated with a coconut water kefir (CWK) starter culture containing 9.60 log CFU/mL of L. plantarum, without dry yeast and fermented for 24 h, had significantly higher values for almost all amino acids and a lower protein content compared to samples formulated using CWK cultures containing 8.30 log CFU/mL of L. fermentum and 4.90 log CFU/mL of L. fermentum, both without dry yeast and fermented for 24 h. The bread sample formulated with CWK starter culture containing 9.60 log CFU/mL of L. plantarum, without dry yeast and fermented for 24 h, also produced significant quantities of organic acids (pyruvic acid, acetic acid, lactic acid and succinic acid). These changes in the physicochemical properties can improve overall bread quality in terms of flavor, shelf life, texture and nutritional value.


1988 ◽  
Vol 51 (5) ◽  
pp. 386-390 ◽  
Author(s):  
Y. A. EL-SAMRAGY ◽  
E. O. FAYED ◽  
A. A. ALY ◽  
A. E. A. HAGRASS

The traditional yogurt starter, i.e. Staphylococcus thermophilus and Lactobacillus bulgaricus, has always been used to bring about the lactic acid fermentation during manufacture of concentrated yogurt known in Egypt as “Labneh”. Different combinations of some strains of Enterococcus faecalis, isolated from Laban Rayeb (a type of fermented milk), in combination with a certain strain of Lactobacillus bulgaricus were used to produce a Labneh-like product. Chemical, microbiological and organoleptic properties of the Labneh-like product were assessed and compared to the characteristics of Labneh processed traditionally by two different dairy plants in Egypt. All treatments showed similar changes during storage at 5 ± 1°C for 28 d. Total solids, fat, titratable acidity and pH values coincided with those of Labneh. Some components increased until the seventh day, i.e. acetaldehyde and diacetyl, while other features, such as the ratio of soluble nitrogen/total nitrogen and tyrosine, increased until the fourteenth day of storage. Thereafter, no marked variations occurred. However, a decrease in tryptophan content of all products occurred during the storage period. Total viable count and count of lactic acid bacteria of Labneh-like product as well as Labneh increased until the end of the second week of storage and then decreased. Coliforms, yeasts and molds and psychrotrophic bacteria were detected in some fresh and stored samples. The starter culture which consisted of 1.5% Enterococcus faecalis 19 and 1.5% Enterococcus faecalis 22 was used successfully to manufacture a Labneh-like product with high acceptability when fresh or refrigerated at 5 ± 1°C.


2004 ◽  
Vol 67 (2) ◽  
pp. 403-406 ◽  
Author(s):  
R. D. RAO ◽  
W. L. WENDORFF ◽  
K. SMITH

Whey is often stored or transported for a period of time prior to processing. During this time period, galactose and lactic acid concentrations may accumulate, reducing the quality of spray-dried whey powders in regard to stickiness and agglomeration. This study surveyed industry samples of Cheddar and mozzarella cheese whey streams to determine how galactose and lactic acid concentrations changed with storage at appropriate (4°C) and abuse (37.8°C) temperatures. Samples stored at 4°C did not exhibit significant increases in levels of lactic acid or galactose. Mozzarella whey accumulated the greatest amount of galactose and lactic acid with storage at 37.8°C. Whey samples derived from cheese made from single strains of starter culture were also evaluated to determine each culture's contribution to galactose and lactic acid production. Starter cultures evaluated included Streptococcus salivarius ssp. thermophilus, Lactobacillus helveticus, Lactobacillus delbrueckii ssp. bulgaricus, Lactococcus lactis ssp. cremoris, and Lactococcus lactis ssp. lactis. Whey derived from L. helveticus accumulated a significantly greater amount of lactic acid upon storage at 37.8°C as compared with the other cultures. Galactose accumulation was significantly decreased in whey from L. lactis ssp. lactis stored at 37.8°C in comparison with the other cultures. Results from this study indicate that proper storage conditions (4°C) for whey prevent accumulation of galactose and lactic acid while the extent of accumulation during storage at 37.8°C varies depending on the culture(s) used in cheese production.


2001 ◽  
Vol 64 (1) ◽  
pp. 81-86 ◽  
Author(s):  
A. OUMER ◽  
S. GARDE ◽  
P. GAYA ◽  
M. MEDINA ◽  
M. NUÑEZ

The effects of bacteriocins produced by six strains of lactic acid bacteria on 9 mesophilic and 11 thermophilic commercial starter cultures were investigated in mixed cultures of commercial starters with bacteriocin-producing strains in milk. The bacteriocins produced by the test organisms were nisin A, nisin Z, lacticin 481, enterocin AS-48, a novel enterocin, and a novel plantaricin. Mesophilic commercial starters were in most cases tolerant of bacteriocins, with only two of the starters being partially inhibited, one by four and the other by two bacteriocins. The aminopeptidase activities of mesophilic starters were generally low, and only one of the combinations of mesophilic starter–bacteriocin producer gave double the aminopeptidase activity of the starter culture without the bacteriocin producer. Thermophilic commercial starters were more sensitive to bacteriocins than mesophilic starters, with six thermophilic starters being partially inhibited by at least one of the bacteriocins. Their aminopeptidase activities were generally higher than those of the mesophilic starters. The aminopeptidase activities of seven thermophilic starters were increased in the presence of bacteriocins, by factors of up to 9.0 as compared with the corresponding starter cultures alone. Bacteriocin-producing strains may be used as adjunct cultures to mesophilic starters for the inhibition of pathogens in soft and semihard cheeses, because mesophilic starters are rather tolerant of bacteriocins. Bacteriocin producers may also be used as adjunct cultures to thermophilic starters of high aminopeptidase activity, more sensitive to lysis by bacteriocins than mesophilic starters, for the acceleration of ripening in semihard and hard cheeses.


2013 ◽  
Vol 6 (4) ◽  
pp. 411-418 ◽  
Author(s):  
G. Comi ◽  
L. Chiesa ◽  
S. Panseri ◽  
S. Orlic ◽  
L. Iacumin

Penicillium nordicum is the main ochratoxin A (OTA)-producing fungal species isolated from artisanal sausages of different areas of Italy and other European countries. P. nordicum grows on and produces OTA in the sausage casing, thereby posing a health risk to Italian consumers, who commonly eat both the meat and casing of artisanal sausages. Different methods have been proposed to eliminate OTA and P. nordicum on the casings, including brushing, brushing and washing, the use of fungal starter cultures (Penicillium nalgiovense) and gaseous ozone. The aim of this study was to compare these methods with regard to eliminating the risk of OTA contamination in sausages. Three concentrations of gaseous ozone were assessed, i.e. 0.5, 1.0 and 1.5 mg/l. Only 1.5 mg/l prevented P. nordicum growth and production of OTA in sausages without influencing the physicochemical parameters and the sensory characteristic of the products. Application of this gaseous ozone concentration was then compared to the other methods, i.e. brushing, brushing and washing, a one-step starter culture of P. nalgiovense (inoculation after casing) and a two-step starter culture (inoculation after both casing and drying). The results obtained showed that only the use of gaseous ozone and a two-step starter culture of P. nalgiovense achieved complete inhibition of P. nordicum growth and OTA production. However, sensory analysis of the treated sausages showed that the use of starter cultures was the best method.


2017 ◽  
Vol 9 (1) ◽  
pp. 551-555 ◽  
Author(s):  
Preeti Goyal ◽  
Lakshman Kumar Chugh ◽  
Mukesh Kumar Berwal

The present investigation was conducted to study the effect of storage period on flour quality of wheat, maize and pearl millet. Their flour were stored at 15 °C and 82 % relative humidity RH for one month and changes in fat acidity (FA), activities of peroxidase (POX), lipoxygenase (LOX) and polyphenol oxidase (PPO) in control and stored flour along with change in pH of water extract of flour were monitored. Increase in FA (mg KOH/100 g d.m.) and decrease in pH of flour was maximal in pearl millet (287.5 mg KOH/100 g d.m. and 0.4) followed by maize (151 mg KOH/100 g d.m. and 0.23) and wheat (61 mg KOH/100 g d.m. and 0.1) respectively. A decline in activity of POX, LOX and PPO was observed during storage. Pearl millet flour possessed almost double activity of POX (413 Units/g d.m.) in comparison to wheat (198 Units/g d.m.) and 1.3 fold higher than that of maize (153 Units/g d.m.) and even after decrease activity of POX was higher in flour of pearl millet compared to the other two. However, activity of LOX and PPO was found to be comparable in fresh flour of pearl millet, maize and wheat. Since pearl millet has poor shelf life and increase in FA, decrease in pH and activity of POX was found to be very high in pearl millet (poor shelf life) as compared to wheat and maize, therefore, these selected parameters might be used as biochemical markers to determine shelf life of flour.


2019 ◽  
pp. 64-75
Author(s):  
А. I. Tykhonov ◽  
T. G. Yarnykh ◽  
S. G. Bobro ◽  
O. S. Shpychak

In modern conditions, the incidence of acne, which is a polymorphic multifactorial disease of the sebaceous glands of the skin, has a tendency to significant growth. Localization of lesions on the face in almost all patients indicates the fact that acne has an effect on their psycho-emotional sphere and social adaptation, which makes this problem urgent and indicates the feasibility of creating new effective domestic medicines for treating this pathology. The aim of the work was to conduct research on the investigation of quality indicators and studying the stability of «Propolis-AK» gel of anti-inflammatory and antimicrobial action for the treatment of acne disease. The objects of research were model test-samples of «Propolis-AK» gel, for which were developed methodic for analyzing the qualitative composition and quantitative content of the active substances – propolis phenolic hydrophobic drug (PPHD) and azelaic acid (AA) in this dosage form, comprehensively allowing to evaluate the quality and criteria for the stability of the gel during the entire storage period for the following indicators: description, identification, homogeneity, tightness of the container, pH, package contents, microbiological purity, quantification. In addition, the requirements for packaging, labeling, transportation, storage conditions and shelf life were included in the draft of quality control methods. According to the results of the study of organoleptic and physical-chemical parameters of the developed «Propolis-AK» gel during storage at two temperature conditions (8‒15 °C and 15‒25 °C), it was found that the test samples of the gel under study remained fairly stable according to the studied indicators for 2 years and 3 months, which allows us to recommend a shelf life of 2 years at room temperature in aluminum tubes for the studied gel. According to the results of research, a specification for «Propolis-AK» gel for external use was developed as a component of the draft of quality control methods for the studied medicine. Studies have been conducted to establish the main indicators and methods of quality control of the developed «Propolis-AK» gel for the treatment of acne disease. According to the results of the tests, a “Specification” was developed, which was included in the draft of quality control methods and experimentally proved the stability of «Propolis-AK» gel prepared in pharmaceutical and industrial conditions for a prescribed shelf life of 24 months when stored in aluminum tubes with an internal lacquer coating in a cool place (8‒15 °C) and at room temperature (15‒25 °C).


2013 ◽  
Vol 20 (1-2) ◽  
pp. 153-162 ◽  
Author(s):  
MA Ejaz ◽  
FH Shikha ◽  
MI Hossain

Improved fish burger was developed from pangus fish (Pangasius sutchi) by using different kinds of food additives (25% mashed potato, 2% NaCl, 2% oil, 2% spices such as onion, ginger, garlic, green chili, hot spices and 0.6% sugar). Proximate composition and sensory, chemical and microbiological changes of pangus fish burger were determined to evaluate the shelf life and storage stability kept at room (28ºC) and refrigeration (5ºC) temperature. It was observed that, the moisture, pH and protein contents in pangus burger were decreased than that of fish mince. On the other hand, lipid and ash contents were higher. Among the variable levels of mashed potato level, 25% mashed potato level showed the best sensory performance and was recommended for the commercial production. At room temperature, the sensory attributes deceased significantly (P<0.05) throughout the storage period. On the other hand, at refrigerated temperature (5°C) the product was more stable. The TVB-N value increased progressively throughout the storage period (P<0.05) at both room (28°C) and refrigerated (5°C) temperature. The microbial load was also increased significantly (P<0.05) at both temperatures but the growth pattern was slower at refrigeration temperature. After considering all the results, it was concluded that, the shelf life of pangus fish burger was very short, in fact not more than 24 hours at 28ºC. On the other hand at 5ºC pangus fish burger may remain in good condition up to 72 hours.DOI: http://dx.doi.org/10.3329/pa.v20i1-2.16867 Progress. Agric. 20(1 & 2): 153 – 162, 2009


Author(s):  
Firuze Emilia Ergin

In this study, the effects of the incubation temperature and type of starter culture on the physical properties, including graininess and visual roughness, of ayran were determined. Ayran samples were produced from milk inoculated with two different starter cultures (Yo-Mix 410, Yo-Mix 883) and incubated at temperatures of 37 or 45°C, and then stored at 4°C for 15 days. As incubation temperature decreased the number and perimeter of grains and syneresis decreased and the amount of exopolysaccharide (EPS) increased in ayran samples. The high amount of EPS resulted in low syneresis value, the number and perimeter of grains and visual roughness in ayran samples. The apparent viscosity and consistency coefficient values of ayran samples produced from milk incubated at 37°C were higher than those from milk incubated at 45°C. The Power law model was found more satisfactory to describe flow behaviour of all ayran samples. The rheological properties of ayran samples changed with measurement temperature. As the measurement temperature increased from 5°C to 15°C, the apparent viscosity and consistency coefficient values of ayran samples were significantly decreased. The activation energy values for apparent viscosity of ayran samples varied depending on the incubation temperature, type of starter culture and storage period.


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