• Food Science and Preservation
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• v.20 no.5
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• pp.712-719
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• 2013

This study was conducted to investigate the antibacterial activity of lactic acid bacteria isolated from traditional fermented foods and to develop a new starter for fermented milk. The isolates were identified using 16S rDNA sequencing and named Lactobacillus plantarum A, Leuconostoc lactis B and L. acidophilus C. The activity of these strains to inhibit the growth of food-borne human pathogens (Escherichia coli NCTC 12923, Salmonella Typhimurium NCTC 12023, Listeria monocytogenes NCTC 11994) was measured using the paper disc method. All these strains showed strong antibacterial activity against Li. monocytogenes NCTC 11994. The experiment groups were the fermented milks with these strains, and the control group was the fermented milk with the commercial starter (ABT 5). The change of pH, acidity and viable cell counts were measured during their aging time. All the experiment groups showed a significant difference in their aging times compared to the control group. However, the sensory test showed that the experiment groups can be used as useful starters for fermented milk. This result suggests that L. plantarum A, Leu. lactis B and L. acidophilus C have the potential to be developed as new starters for fermented milk.

• Culinary science and hospitality research
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• v.20 no.3
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• pp.90-99
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• 2014

Tarak is our own traditional fermented milk, which is made from lactic acid fermentation by using makgeolli as inoculum for milk or fermented by using Tarak that had already made. we made our own traditional fermented milk and Tarak Pudding by the traditional fermented milk, and then, we investigated the quality characteristics of Tarak Pudding on the addition rates of Tarak. As a result, the more the amount of Tarak, the more the contents of crude protein, crude fat and crude ash of Tarak Pudding according to the percentage of addition of Tarak meaningfully, except for its moisture content (p<0.05). While the pH decreased with more Tarak, the acidity significantly increased. In the case of sugar content, TP 1, 2, and 3 were higher than the control group, and TP 4 showed the higher sugar content(p<0.05). As the result of measurement of chromaticity of Tarak Pudding, the L value of the control group was 38.80. However, it increased with more addition of Tarak, while a value decreased. For the b value, it significantly increased with more Tarak. In the measure of texture, there were significant differences between the control group and the samples in hardness, springiness, cohesiveness, chewiness, and adhesiveness (p<0.05). The sensory evaluation result showed that there were meaningful differences among the samples in their appearance, taste, flavor, texture and overall acceptance. However, due to distinctive sour and odor of Tarak, TP 3 (75% addition) than TP 4 (100% addition) was considered to be desirable.

• The Korean Journal of Food And Nutrition
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• v.23 no.4
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• pp.462-469
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• 2010

This study was conducted to investigate the physicochemical properties of Kefir. The general composition of Kefir cultured in skim milk or milk was, respectively, 90.0 and 87.8% water, 3.2 and 3.0% protein, 0.45 and 3.64% lipid, 3.96 and 4.14% lactose, and 0.77 and 0.68% ash. Titratable acidity(TA) and pH of Kefir were 0.77 and 4.55, respectively. The amount of $CO_2$ production was 6.23%, and the concentration of alcohol was 1.4%. Kefir grain as observed by scanning electron microscope was a complex mixture of lactic acid bacteria and yeast in a symbiotic association.

• Journal of Dairy Science and Biotechnology
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• v.37 no.4
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• pp.247-255
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• 2019

The objective of this study was to evaluate the sensory profiles of market milk, yogurt, and kefir, supplemented with the powder of Hibiscus sabdariffa Linnaeus (Roselle) in 1% increments, ranging from 0% (control) to 4%. In this study, there was no statistically significant difference in titratable acidity and pH between the treated groups and the control group. All samples were evaluated in five categories by thirteen appraisers. Compared to the control group, the best sensory profiles were observed in the market milk sample supplemented with 1.0% of Hibiscus sabdariffa Linnaeus (Roselle) powder, in the yogurt samples supplemented with 2.0% and 3.0% of Hibiscus sabdariffa Linnaeus (Roselle) powder, and in the Kefir sample supplemented with 3% of Hibiscus sabdariffa Linnaeus (Roselle) powder. According to statistical analysis of the sensory profiles obtained in this study, there was a statistical difference in the taste, flavor, color, and overall acceptability of market milk; in the taste, color, texture, and overall acceptability of yogurt; and in the taste, color, and overall acceptability of Kefir, between the treated groups and the control group (p<0.05). In the future, when Hibiscus sabdariffa Linnaeus (Roselle) powder is used as a food additive for dairy products, studies on improvement of biofunctionality, as well as of sensory profiles in dairy products must be carried out.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.365-365
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• 2017

Yogurt is a food produced by bacterial fermentation of milk and the bacteria used to make it are known as "yogurt cultures". Most of them belong to probiotics such as Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. Domestic fermented milk market is increasing and about 30 companies are producing yogurt. The purpose of this study was to analyze the quality characteristics of domestic commercial semisolid type yogurt. We collected 20 types of commercial yogurt at local markets. Physicochemical properties including pH, sugar content, acidity, viscosity and microbial characteristics of lactic acid bacteria counts were measured. The yogurt showed pH 4.5, 7.4~18.1% of sugar contents, 0.6~1.3% of total acids and 282~748 cP of viscosities. In the microorganism populations, lactic acid bacteria count were 6.5~11.5 Log CFU/mL and anaerobic lactic acid bacteria count were 7.2 ~ 11.1 Log CFU/mL. The quality characteristics were different depending on the constituents of the sample and the microorganisms used. These results are related to the quality characteristics of yogurts which are useful information about identifying new trends in domestic fermented milk industry.

• Journal of Food Hygiene and Safety
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• v.12 no.3
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• pp.175-180
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• 1997

Escherichia coli O157:H7 and Salmonella ser. typhimurium are pathogens involved in food poisoning in numerous countries. This study aimed to obtain knowleges on the survival of E. coli O157:H7 KSC 109 and S. ser. typhimurium ATCC 14028 in fermentedmilk products which were on sale in Suwon Yakult supplier. To the final concentration of 103~104 cfu/$m\ell$ of E. coli O157:H7 KSC 109 or S. wer. typhimurium ATCC 14028 in the fermented milks, Metchnikoff, Ace, Yakult, Mastoni and Super 100 were inoculated with these pathogens and then were stored at 4$^{\circ}C$ and viable cells of these pathogens were periodically counted. The results showed that the survival of two pathogens differed in the different types of fermented milks tested. Number of suriviving E. coli O157:H7 KSC 109 and S. ser. typimurium ATCC 14028 cells (initial inoculum, 103~104 cfu/$m\ell$) were decreased to 101, 102 cfu/$m\ell$ in Ace after 100 hours, and were decreased gradually to 101 cfu/$m\ell$ in Yakult after 250 hours. In the other fermented milks, viable cells of E. coli O157:H7 KSC 109 was not drastically decreased but those of S. ser. typhimurium ATCC 14028 was decreased gradually to 102 (Mastoni), and to 101 cfu/$m\ell$ (Super 100) after 250 hours. It appeared that S. ser. typhimurium ATCC 14028 was more susceptible than E. coli O157:H7 KSC 109 at low pH. Vibale cells of E. coli O157:H7 KSC 109 was not drastically decreased in most of fermented milks tested except Ace and Yakult, but in general, S. ser. typhimurium ATCC 14028 was drastically decreased in most of the fermented milks. The major ingibition factor against these pathogens in the fermented milks during storage at 4$^{\circ}C$ appeared to be the acidity and the metabolites produced by the starters bacteria used in fermented milk products.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.571-582
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• 2022

Cacao, a major ingredient for making chocolate, has been shown to have potent antioxidant effects. The consumption of raw cacao has beneficial effects on health. This study determined the fermentation properties of yoghurt that was manufactured with cacao nibs (Theobroma cacao L.). The pH of the yogurt containing the cacao nibs was lower than that of the control, and this reduction was both concentration and fermentation time-dependent. Furthermore, the number of lactic acid bacteria in the yogurt made with cacao and its viscosity increased in a cacao nibs dependent manner. In particular, the yoghurt with 5% cacao nibs added had the highest number of lactic acid bacteria at 48 hours at the end point of the fermentation. Whey protein degradation in yogurt containing cacao nibs increased with the fermentation time, and the organic acid production, especially lactic acid, in the yogurt containing cacao nibs increased significantly after 16 hours of fermentation. In addition, the total polyphenol content of the yogurt containing cacao nibs increased, which was proportional to the amount added. Sensory evaluations of the yogurts indicated that overall taste was less desirable as cacao nib loadings increased from 1 to 5% compared with controls. This result is due to the excessive acidity, which was strongly perceived in the absence of added sugar. The development of yogurts with cacao nibs is expected to contribute much to the appeal of fermented milk.

• Food Science of Animal Resources
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• v.43 no.4
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• pp.659-673
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• 2023

Compared to infant formula, breast milk is the best source of nutrition for infants; it not only improves the neonatal intestinal function, but also regulates the immune system and gut microbiota composition. However, probiotic-fortified infant formula may further enhance the infant gut environment by overcoming the limitations of traditional infant formula. We investigated the probiotic formula administration for one month by comparing 118 Korean infants into the following three groups: infants in each group fed with breast milk (50), probiotic formula (35), or placebo formula-fed group (33). Probiotic formula improved stool consistency and defecation frequency compared to placebo formula-fed group. The probiotic formula helped maintaining the level of secretory immunoglobulin A (sIgA), which had remarkably decreased over time in placebo formula-fed infants (compared to weeks 0 and 4). Moreover, probiotic formula decreased the acidity of stool and considerably increased the butyrate concentration. Furthermore, the fecal microbiota of each group was evaluated at weeks 0 and 4. The microbial composition was distinct between each groups, and the abundance of health-promoting bacteria increased in the probiotic formula compared to the placebo formula-fed group. In summary, supplementation of probiotic infant formula can help optimize the infant gut environment, microbial composition, and metabolic activity of the microbiota, mimicking those of breast milk.

• Korean journal of food and cookery science
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• v.22 no.1 s.91
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• pp.22-29
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• 2006

Yogurt base was prepared from milk powder $(14\sim18%)$ to which was added 0.4% Saururus chinensis (Lour.) Bail water extract (SCE) and fermented with lactic acid bacteria (a mixed strain of Streptococcus thermophilus and Lactobacillus bulgaricus) at $37^{\circ}C$ for 24 hr. The viscosity of the yogurt added SCE (SCE yogurt) made from 18% milk was higher than that of SCE yogurt containing $14\sim16%$ milk, whereas the pH and titratable acidity of the SCE yogurt were not significantly different on the range of milk contents. The optimal milk concentration for SCE yogurt manufacture was 18%. In order to optimize the preparation of dressing from SCE yogurt, the central composite design was conducted in terms of the yogurt (30, 40, 50, 60, 70 g), the mayonnaise (6, 12, 18, 24, 30 g) and the salt (0.1, 0.3, 0.5, 0.7, 0.9 g) contents. Sensory evaluation was performed and evaluated using a response surface methodology. The optimum ingredient ratio for SCE yogurt dressing was determined to be 61.2% of yogurt, 23.5% of mayonnaise, 0.58% of salt, 0.58% of honey, 1.75% of mustard, 0.23% of Tabasco pepper sauce, 0.94% of wine and 0.04% of white pepper.

• Journal of Nutrition and Health
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• v.14 no.4
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• pp.175-181
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• 1981

This study was carried out to investigate the feasibility of production of soy yogurt, which is inexpensive and high protein product with an acceptable flavor, from soy milk using lactic acid bacteria. Utilization of various carbohydrates by Lactobacillus acidophilus, Streptococcus thermophilus and Lactobacillus bulgaricus was stuied. Sucrose, the major carbohydrate in soymilk, was fermented by L. acidophilus and S. thermophilus. None of the testing microorganisms was able to ferment melibiose and raffinose. Growth of lactic acid bacteria in soymilk was examined every 4 hour. L. acidophilus exhibited the highest growth rate during the early stage. After 16 hours of incubation, however, all the cultures with the exception of L. bulgaricus grew at nearly equal rates. Microscopic examination of mixed cultures showed that the presence of S. thermophilus was much more pronounced than that of L. bulgaricus. All the cultures with the exception of L. bulgaricus formed acid rapidly during 16 hours of incubation, bringing the titratable acidity to 0.6% and pH to 4.3, which was sufficient to cause coagulation of soymilk. L. bulgaricus produced acid to a much lesser extent and caused coagulation of soymitk after 30 hours at earliest. Three kinds of yogurts were prepared from 100% soymilk, 100% milk and 50% soy-50% milk combination by S. thermophilus and were evaluated by taste panel. Soy yogurt received a significantly lower mean odor score than milk yogurt. Soy yogurt had custardlike texture, while milk yogurt was syrupy. However the scores for texture as well as those for color and flavor did not differ significantly among the treatment. The mean total scores for yogurts were not significantly different and were equivalent to ratings between good and high fair.