• Korean journal of food and cookery science
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• v.7 no.2
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• pp.89-95
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• 1991

The effects of lactic acid bacteria on the chemical and microbial changes of fermented kimchi at various temperatures were studied. Kimchi was homogenized and was sterilized by ultra violet (UV), then Lactobacillus plantarum, Leuconostoc mesenteroides, Pediococous acidilactici, Lactobacillus brevis and the mixture of these bacteria inoculated on sterilized kimchi, respectively. The measurement of alcohol by gas chromatography, and changes of sugar content and total viable count were investigated and palatability test was carried while inoculated kimchi was fermented at $30^{\circ}C$, $21^{\circ}C$ and $7^{\circ}C$. Ethyl alcohol was detected by GC in sample I (original Kimchi homogenate), III(inoculated Leu. mesenteroides), V(inoculated with Lac. brevis), then especially, more content were detected at $14^{\circ}C$. Sugar content reduced in accordance with fermentation proceeding. Total viable count increased at early fermentation stage, but thereafter decreased slowly. In the result of palatability test, sample I was the highest at all temperatures, sample III and IV (inoculated with mixed lactic acid bacteria) was the following in that kimchi odor and taste and the temperature.

• Korean Journal of Food Science and Technology
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• v.54 no.4
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• pp.445-454
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• 2022

This study aimed to improve the physiological activity of onion juice via lactic acid bacterial fermentation. Seven types of lactic acid bacteria were used for the fermentation of onion juice. The pH and sugar content of the onion juice decreased, while its titratable acidity increased after lactic acid bacteria fermentation, and the cell count of lactic acid bacteria was 7.31-10.40 log CFU/mL. The total free sugar content decreased, while the total organic acid content increased in the fermented onion juice. Quercetin content of the fermented juice was 0.13-0.53 mg/kg. The total polyphenol and flavonoid contents increased after fermentation. Additionally, the 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate) radical cation scavenging activities were increased by fermentation. Overall, lactic acid bacteria fermentation of onion juice enhanced its physiological activity. Based on these findings, Bifidobacterium breve KCTC 3441 was selected as the onion juice fermentation strain.

• Food Science of Animal Resources
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• v.42 no.6
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• pp.1009-1019
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• 2022

In recent years, biocontrol of foodborne pathogens has become a concern in the food industry, owing to safety issues. Listeria monocytogenes is one of the foodborne pathogens that causes listeriosis. The major concern in the control of L. monocytogenes is its viability as it can survive in a wide range of environments. The purpose of this study was to isolate lactic acid bacteria with antimicrobial activity, evaluate their applicability as a cheese starter, and evaluate their inhibitory effects on L. monocytogenes. Lactococcus lactis strain with antibacterial activity was isolated from raw milk. The isolated strain was a low acidifier, making it a suitable candidate as an adjunct starter culture. The commercial starter culture TCC-3 was used as a primary starter in this study. Fresh cheese was produced using TCC-3 and L. lactis CAU2013 at a laboratory scale. Growth of L. monocytogenes (5 Log CFU/g) in the cheese inoculated with it was monitored during the storage at 4℃ and 10℃ for 5 days. The count of L. monocytogenes was 1 Log unit lower in the cheese produced using the lactic acid bacteria strain compared to that in the cheese produced using the commercial starter. The use of bacteriocin-producing lactic acid bacteria as a starter culture efficiently inhibited the growth of L. monocytogenes. Therefore, L. lactis can be used as a protective adjunct starter culture for cheese production and can improve the safety of the product leading to an increase in its shelf-life.

• Food Science of Animal Resources
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• v.44 no.2
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• pp.372-389
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• 2024

This study investigated the efficacy of ultraviolet-C (UV-C) irradiation in enhancing the quality of raw bovine milk by targeting microbial populations and lipid peroxidation, both of which are key factors in milk spoilage. We categorized the raw milk samples into three groups based on initial bacterial load: low (<3 Log 10 CFU/mL), medium (3-4 Log 10 CFU/mL), and high (>4 Log 10 CFU/mL). Using a 144 W thin-film UV-C reactor, we treated the milk with a flow rate of 3 L/min. We measured the bacterial count including standard plate count, coliform count, coagulase-negative staphylococci count, and lactic acid bacteria count and lipid peroxidation (via thiobarbituric acid reactive substances assay) pre- and post-treatment. Our results show that UV-C treatment significantly reduced bacterial counts, with the most notable reductions observed in high and medium initial load samples (>4 and 3-4 Log 10 CFU/mL, respectively). The treatment was particularly effective against coliforms, showing higher reduction efficiency compared to coagulase-negative staphylococci and lactic acid bacteria. Notably, lipid peroxidation in UV-C treated milk was significantly lower than in pasteurized or untreated milk, even after 72 hours. These findings demonstrate the potential of UV-C irradiation as a pre-treatment method for raw milk, offering substantial reduction in microbial content and prevention of lipid peroxidation, thereby enhancing milk quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1693-1700
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• 2012

In this study we examined the antioxidant activity and fermentation characteristics of black rice wine. The antioxidant activity of black rice wine was higher than the control, and DPPH radical scavenging activity showed a correlation with the anthocyanin content of rice wine. The pH remarkably decreased until 3 days of fermentation, and the gradually decreased. The reducing sugar and free sugar content reached a maximum at 1 day of fermentation due to enzyme activity. The amount of organic acids, especially lactic acid, increased during the fermentation period. Lactic acid bacteria and yeast count increased with time and amount of black rice. The L color value increased during fermentation regardless of treatments, and the a color value increased with ratio of black rice due to anthocyanin. For this reason, color was given a high score in black rice wine. But overall preference was high in rice wine made with less than 20% of black rice.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.219-224
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• 1992

The changes of yeast population were investigated in Mul-kimchi containing 3% salt, fermented at $15^{\circ}C$. The total viable count increased to the maximum at the optimum ripening period and then decreased rapidly. Among twenty-nine strains isolated at the optimum ripening period, the yeasts of genus Saccharomyces were predominant. The growth of five strains, Saccharomyces saitoanus Y17, Saccharomyces capensis Y29, Saccharomyces chevalieri Y13, Kluyveromyces fragilis Y2, Torulopsis candida Y9, was measured in mixed culture with each selected lactic strains, hctobaczllus plantarum Lp2, Pedzococcus pentosaceus PI, Leuconostoc mesenteroides Lu5. The results indicated that all the yeasts tested were inhibited significantly by lactic strains, however the sensitivity of yeast strains varied greatly.

• Journal of Dairy Science and Biotechnology
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• v.41 no.2
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• pp.76-85
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• 2023

This study investigated the effect of the addition of pomegranate concentrate to yogurt on the growth of pathogenic and lactic acid bacteria. The concentration of the MRS broth was adjusted to one-half and used for an experiment. Pomegranate concentrate was added at concentrations of 4%, 2%, 1%, and 0.5%, which significantly promoted the growth of Lacto-coccus cremoris, Weissella cibaria, Weissella paramesenteroides, Lactobacillus plantarum, Lactobacillus acidophilus, Streptococcus thermophillus, Lactobacillus bulgaricus, and Lactobacillus lactis. The growth of lactic acid bacteria increased with higher concentrations of pomegranate. However, the addition of pomegranate concentrate inhibited the growth of Escherichia coli KCCM11587, E. coli KCCM11591, E. coli KCCM11596, and E. coliKCCM11600. Yogurt with added pomegranate concentrate demonstrated optimal conditions compared to that of the control without the addition. Particularly, the viable cell count of lactic acid bacteria was significantly higher in the yogurt with pomegranate concentrate. Furthermore, the viability of the lactic acid bacteria in the yogurt with pomegranate concentrate was higher than that of the control without the addition of concentrate during storage.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.415-419
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• 2002

The replacement effects of cheese far salted and fermented fish on growth of lactic acid bacteria, fermentation velocity and sensory characteristics of Kimchi were investigated. In both control and cheese Kimchi, the total viable cell count of lactic acid bacteria was increased rapidly during the initial 2 days of fermentation. From 3 days after preparation, Kimchi added with cheese showed higher number of lactic acid bacteria than control Kimchi. The pH of Kimchi decreased rapidly after a small increase at the first day of fermentation, reaching 4.18-4.33 at the third day of fermentation, and the pH was slightly lower in Kimchi added with cheese than in control. Proximate analysis of Kimchi added with cheese was slightly higher in moisture and lower in crude protein and fat than control Kimchi. Sensory evaluation of the Kimchi fermented for 3 days showed that the Kimchi added with 3 or 5% of cheese had higher scores of appearance, flavor and overall taste than the control Kimchi.

• The Korean Journal of Food And Nutrition
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• v.21 no.1
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• pp.51-55
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• 2008

Colour and texture are the most difficult quality aspects of Kimchi to maintain during storage. Therefore, this study investigated how to maintain superior quality Kimchi during fermentation without changes in color and texture. By examining differences between samples covered with vinyl(A group) and not covered with vinyl(B group) and assessing pH, total acidity, total viable cell count, total lactic acid bacteria cell count and sensory characteristics. The results are indicated that pH, total acidity, total viable cell and total lactic acid bacteria were similar between group A and B. Group A showed higher sensory score for colour, taste, texture and acceptability than group B(p<0.001). Covering the Kimchi with vinyl appeared to have a similar effect as when Kimchi is kept in a Kimchi-pot under stones or the outer leaves of vegetables making it possible to maintain good color and texture during storage. In conclusion, even though, it is not practical to use Kimchi-pots within urban settings today, vinyl coverings may offer the same effects.

• The Korean Journal of Food And Nutrition
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• v.3 no.1
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• pp.13-22
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• 1990

Nangmyun-broth was collected as samples from 25 common restaurants in Bucheon to examine it's sanitary condition. The main course of bacterial contamination was persuited for it's sanitary improvement. Bacterial count in summer sample was not greatly different from that in winter, resulting in total count 1.7$\times$10i1m1, lactic acid bacteria 8.7$\times$106/ml, coliform group 1 2$\times$105/ml, Staphylococcus aureus 6.5$\times$102/ml. Bacterial contamination occurred remarkably with the use of storage barrel in which remnent Nangmyun-broth was still resting, because the remnant Nangmyun-broth contained high level of bacteria Good santary condition in Nangmyun-broth was obtained by the use of clean barrel which had been washed with tap water or sterilizied with steam before filling fresh Nangmyun -broth for cold storage. The growth of Escherichia coli and Staphylococcus aureus was inhibited in the presence of acetic acid(0.01~0.05%) or mustart(0.1~0.5%)