• Korean journal of food and cookery science
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• v.31 no.6
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• pp.725-732
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• 2015

This study was conducted to evaluate the effects of ethanol on the prolongation of the shelf-life of kimchi paste. Kimchi paste was prepared by adding 0.5~3.0% ethanol, and then stored at $4^{\circ}C$ for 35 days. The retardation of kimchi paste fermentation was evaluated by measuring chemical, microbial, and sensory characteristics. Titratable acidity and pH showed a slight difference, depending on the ethanol concentration. The titratable acidity showed the low content in kimchi paste with 3.0% ethanol during fermentation, whereas the pH showed a reverse tendency, indicating that fermentation was inhibited under a high ethanol concentration. The changes in the sugar-reduced contents were similar to that of the pH. The growth of microorganisms such as total aerobic bacteria, lactic acid bacteria, yeasts and molds in kimchi paste during fermentation were inhibited by ethanol, and the addition of 3.0% ethanol was most effective to inhibit the microbial growth. The number of coliform bacteria was decreased during fermentation of kimchi paste and not detected in any sample at 35 days, except for kimchi paste with 3.0% ethanol. In sensory evaluation, the addition of 0.5~1.5% ethanol in kimchi paste was showed no significant difference on sensory properties compared to the kimchi paste without ethanol (p<0.05). As a result, it is considered that the addition of 1.5% ethanol is the most appropriate to maintain the quality of kimchi paste, without the changing the flavor.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.4
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• pp.305-312
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• 2003

The effect of addition of ethanol and/or organic acid on slowing down the fermentation of Mul-kimchi was tested by measuring the changes in pH, acidity and counting the number of microorganisms in kimchi fermentation, and sensory evaluation were carried out. The addition of 0~5％ ethanol to kimchi delayed the decrease of pH and the delaying effect during kimchi fermentation was dependent on the ethanol concentration used. The pH of kimchi without ethanol decreased from 5.7 to 4.13, however, the pH of the kimchi added with 5％ ethanol only from 5.8 to 5.14. The increase of acidity in kimchi with 5％ ethanol was only 0.5~0.6％, while that without ethanol was 0.7~0.8％. Among the organic acids tested, adipic acid was found to be most effective on the prevention of kimchi souring. The Mul-kimchi added 2％ ethanol together with 0.1％ organic acid showed similar effect to that of organic acid alone in the change of pH and acidity. By the sensory evaluation, Mul-kimchi with 0.1％ adipic acid and 2％ ethanol was selected the most desirable one except control without any addition. And the numbers of total microbes, lactic bacteria and yeast count, showed the most effective inhibition in Mul-kimchi with 0.1％ adipic acid and 2％ ethanol.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.512-526
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• 2020

Synthetic nitrite is considered an undesirable preservative for meat products; thus, controlling synthetic nitrite concentrations is important from the standpoint of food safety. We investigated 1,000 species of microorganisms from various kimchi preparations for their potential use as a starter culture for the production of nitrites. We used 16S rRNA gene sequence analysis to select a starter culture with excellent nitrite and nitric oxide productivity, which we subsequently identified as Staphylococcus hominis subspecies hominis WiKim0113. That starter culture was grown in NaCl (up to 9%; w/v) at 10℃-40℃; its optimum growth was observed at 30℃ at pH 4.0-10.0. It exhibited nonproteolytic activity and antibacterial activity against Clostridium perfringens, a bacterium that causes food poisoning symptoms. Analysis of Staphylococcus hominis subspecies hominis WiKim0113 with an API ZYM system did not reveal the presence of β-glucuronidase, and tests of the starter culture on 5% (v/v) sheep blood agar showed no hemolytic activity. Our results demonstrated the remarkable stability of coagulase-negative Staphylococcus hominis subspecies hominis WiKim0113, especially in strain negative for staphylococcal enterotoxins and sensitive to clinically relevant antibiotics. Moreover, Staphylococcus hominis subspecies hominis WiKim0113 exhibited a 45.5% conversion rate of nitrate to nitrite, with nitrate levels reduced to 25% after 36 h of culturing in the minimal medium supplemented with nitrate (200 ppm). The results clearly demonstrated the safety and utility of Staphylococcus hominis subspecies hominis WiKim0113, and therefore its suitability as a starter culture.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.267-274
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• 2014

High pressure processing (HPP) is a non-thermal method used to prevent bacterial growth in the food industry. Currently, pasteurization is the most common method in use for most milk processing, but this has the disadvantage that it leads to changes in the milk's nutritional and chemical properties. Therefore, the effects of HPP treatment on the microbiological and chemical properties of milk were investigated in this study. With the treatment of HPP at 600 MPa and $15^{\circ}C$ for 3 min, the quantity of microorganisms and lactic acid bacteria were reduced to the level of 2-3 log CFU/ml, and coliforms were not detected during a storage period of 15 d at $4^{\circ}C$. An analysis of milk proteins, such as ${\alpha}$-casein, ${\beta}$-casein, ${\kappa}$-casein, ${\alpha}$-lactalbumin, ${\beta}$-lactoglobulin by on-chip electorophoresis revealed that the electrophoretic pattern of the proteins from HPP-treated milk was different from that of conventionally treated commercial milk. While the quantities of vitamins and minerals in HPP-treated milk were seen to be comparable to amounts found in raw milk, the enzyme activity of lipase, protease and alkaline phosphatase after HPP treatment was reduced. These results suggest that HPP treatment is a viable method for the control of undesirable microorganisms in milk, allowing for minimal nutritional and chemical changes in the milk during the process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.110-116
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• 2019

To investigate the antagonistic inhibitory effects in a mixed culture between probiotics and various pathogenic microorganisms, 140 probiotics were identified using a 16 rRNA sequencing phylogenetic analysis method, and various probiotics strains were isolated from Korean kimchi from January to December 2016. The antagonistic inhibition test of a mixed culture of four probiotics (Enterococcus faecalis, Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus reuteri) with excellent antimicrobial activity and six pathogenic microorganisms (Candida albicans, Salmonella Enteritidis, E. coli O157:H7, Shigella flexneri, Staphylococcus aureus, and Pseudomonas aeruginosa)showed that the growth of most probiotics strains increased normally after culture, but growth was inhibited almost completely in most pathogenic microorganisms, except for S. Enteritidis. This antagonistic inhibitory effect in vitro was attributed to the low pH of the lactic acid and organic acid produced during fermentation. As a result, four probiotics strains isolated from Korean Kimchi are very likely to be developed as therapeutic agents for female yeast infections and colon and skin care. In the future, these therapeutic agents will help improve public health related to probiotics.

• Journal of the Korean Society of Food Culture
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• v.4 no.3
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• pp.265-269
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• 1989

Korean traditional fermented foods have been diversely developed to enhance taste and flavor while preserving them on a long term basis. For those furthur utilization and development, more efforts to commercialize these products focusing to the consumer's needs should be proceded. In that sence, the fermented foods might be classified into the bioproduct (biofood) and the sterilized. The former defines the non-sterilized such as Kimchi, Jeotkal (fermented fishes), and Jang (fermented soybean products) so as to include various kinds of microorganisms, enzymes and the unknown bioproducts, while the latter defines the sterilized such as soysauce and vinegars proper to the commercialization. In this paper, present R & D status has been reviewed laying stress on Kimchi, Jeotkal and Jang and the mixed fermentation system by the microflora was suggested as a Korean style model for the future R & D direction in these fields.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.430-438
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• 1996

The eleven strains, which could be used lactic and acetic acids as carbon sources, were isolated from kimchi and identified; the strains were facultative microorganisms which could be grown at low temperature (10$\circ$C) and around pH 3.2. As results of morphological, biochemical and physiological tests, 5 species of 3 genera were identified as Debaryomyces coudertii, Pichia edia, Pichia chambardii, Pichia haplophilia and Saccharomyces fermentati. Each strain was grown in basal media. In acidic resistance and acid utilization test, Saccharomyces sp. YK- 17 and Saccharomyces fermentati YK-19 were grown well in basal and YM media containing 0.3% lactic acid. And two strains were grown in basal and YM media containing O.3% lactic acid and 0.6% acetic acid. Since strain YK-19 was grown better at 10$\circ$C than that in 25$\circ$C, strain YK-19 was known to be a psychrophilic strain.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.577-584
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• 2001

An antimicrobially active bacterium which was identified as Bacillus brevis, was isolated from kimchi. The antimicrobial activity was found against various Gram-positive and Gram-negative bacteria including some pathogens food-spoilage microorganisms, and some yeast strains. The antimicrobial activity was especially strong against Bacillus anthracis and Shigella dysenteriae. The strong activity was observed during an early stationary phase in the culture when incubated at $37^{\circ}C$ with initial medium pH of 6.8. The antimicrobial activity was found to be stable at $90^{\circ}C$ for 30 min and in the pH range of 3-11, and it was insensitive to organic solvents including acetone, acetonitrile, ethanol, and methanol. Analysis of the bacterocin on tricine-sodium dodecyl sulfate-polyacrylamide gel suggested a molecular mass of approximately 4.5-6.0 kDa. The antimicrobial substance was characterized as a bacteriocin, because of its proteinaceous nature and low molecular weight. The bacteriocin could potentially be used as a food preservative, because of its thermostable property and broad antimicrobial spectrum.

• Food Science and Preservation
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• v.5 no.1
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• pp.81-87
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• 1998

Antimicrobial activities of the extracts from spices microorganisms related to kimchi fermentation were investigated. 32 kinds of spices such as allspice, mount, basil, bay leaves, caraway, cardamon, celery, chilli powder, chives, cinnamon, clover, coriander, cumin, dill, fennel, garlic, horseradish, marjorarm, mugwort, mustard, nutmeg, onion, oregano, paprika, parsely, pepper, peppermint, rosemary, sage, tarragon, thyme and tumeric were extracted with water, ethyl ether, ethyl acetate and ethanol. Fractions were tested for antimicrobial activities against Lactobacillus plantarum and Leuconostoc mesenteroides, The extracts of 28 kinds of spices except caraway, cardamon, paprika and tarragon by water extraction, those of 29 kinds except arrowroot, paprika and tarragon by ethyl ether extraction, those of 30 kinds except paprika and tarragon by ethyl acetate extraction, and those of 29 kinds except clover, paprika and tarragon by ethanol extraction showed strong antimicrobial activities against Lactobacillus plantarum. On the other hand, the extracts of 28 kinds of spices except caraway, cardamon, paprika and thyme by water extraction, those of 27 kinds except cardamon, cumin, paprika, tarragon and thyme by ethyl ether extraction, thou of 30 kinds except paprika and thyme by ethyl acetate extraction, and those of 28 kinds except cardamon, cumin, paprika and thyme by ethanol extraction showed strong antimicrobial activities against Leuconostoc mesenteroides.

• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.117-121
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• 2001

Changes in antioxidative activity and Angiotensin converting enzyme(ACE) inhibitory activity in juice prepared from Dolsan leaf mustard kimchi (DLMK) ar various fermentation temperatures were investigated. Antioxidative activity of juice from optimally ripened DLMK at 20 and 3$0^{\circ}C$ showed 80 and 83%, respectively. Juice from 10-day fermented DLMK at 3$0^{\circ}C$ showed 62% inhibitory activity against the ACE. In the juice fermented DLMK at 2$0^{\circ}C$~3$0^{\circ}C$, physiological activity was higher than that of the 4~1$0^{\circ}C$. In particular, optimally ripened DLMK at 3$0^{\circ}C$ showed the highest physiological activity. The physiological activity in DLMK juice at the fermentation period increased significantly with an increase in the growth of microbes. Consequently, a maximum physiological activity was shown at the maximum cell number. These results suggest that the microorganisms in DLMK juice would play an important role in the physiological activity.