• Journal of the East Asian Society of Dietary Life
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• v.4 no.1
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• pp.95-104
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• 1994

This study was carried out to investigate the effect of sub-atmosphere on the fermentation and heat treatment after fermentation of Kimchi. When the results from the conditions of atmosphere and under-atmosphere were compared, the growth of lactic acid bacteria was increased but the growth of aerobic bacteria was decreased under 560mmHg and 360mmHg. The number of total microorganism was decreased and simultaneously damaged to the tissue of Kimchi under 0mmHg. Kimchi fermented under 560mmHg and 360mmHg had longer storage duration than that of atmosphere. Among the several conditions, the result of heat treatment under 460-260mmHg was the best. the treatment for 4 minutes at 80$^{\circ}C$, 2 minutes at 100$^{\circ}C$, and 1 minute at 120$^{\circ}C$ was good in tissue states and storage.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.111-117
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• 1998

The effect of chitosan on physicochemical and organoleptic properties of Nabak kimchi was studied during fermentation at 2$0^{\circ}C$ . Viscosity of the juice of Nabak kimchi added with chitosan was lower than that of control group. The viscosity was gradually increased during storage period, especially from 5 days to ,7 days of storage. Initial pH was higher in control group than inchitosan groups. The pH of controlgroup decreased rapidly during 4 days of storage. The pH of chitosan groups was slightly increased during the first 3 days of storage and decreased thereafter. Acidity was rapidly increased from 3 to 5 days. Reducing sugar contents increased up to 3 days and decreased thereafter. Acidity was rapidly increased from 3 to 5 days. Reducing sugar contents increased upto 3 days and decreased therafter. Glutamic acid, alanine, threonine, aspartic acid, proline and valine were the major free amino acids, and as the fermentation preceeded they were increased gradually. There were signigicant differences in saltiness, sourness and aged odor in sensory evaluation of Nabak kimchi solution during fermentation at 2$0^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.257-263
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• 1995

As a primary step to develop natural preservative for extending the shelf-life of kimchi, the effect of 102 edible plants, 21 antimicrobial agents and related compounds on kimchi fermentation was studied. Among 42 oriental medicinal plants tested, Baical skullcap and Assam indigo were found to be highly effective for maintaining the fresh state of kimchi. Although Bugbane, Red mangolia, Bushy sophora, Szechuan pepper, Chinese quince and Scisandre significantly inhibit the growth of Lactobacilli, their effect was not high enough to be used as raw materials for kimchi preservative. When the effect of 32 herbs and spices was tested, peppermint, cinnamon, lemon balm, clove, hop, rosemary, sage, horseradish and thyme showed high antimicrobial activity against kimchi microorganisms. Among them, the effect of clove ranked top. When it was added to fresh kimchi, initial cfu value ($2.4{\times}10^{6}cfu/g$) changed little even after 2 day's fermentation ($2.6{\times}10^{6}cfu/g$). Sensory test was not a good criteria to evaluate the effect of herbs and spices, since their highly specific flavors affected the taste of kimchies. Twenty eight fruits, vegetables and related plants were tested, but only leaves of pine tree, persimmon and oak leaves showed a significant bactericidal effect, finally contributing to the storage of kimchi. In addition, when 21 natural preservatives and other compounds were added individually to fresh kimchi, nisin and caffeic acid could inhibit fermentation.

• Journal of the Korean Society of Food Culture
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• v.25 no.1
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• pp.61-69
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• 2010

This study was carried out to investigate the effects of various kinds of commercial salts, including sun-dried (Korea), purified, and traditional salts on the chemical and sensory properties and growth of microorganisms involved in kimchi fermentation. Kimchi was prepared by salting in 10% NaCl solution for 2 hours followed by addition of other spices and fermentation at $20^{\circ}C$. The decreases in pH suggested that kimchi fermentation can be classified into 3 steps: initial, intermediate, and final stages. In texture analysis, the hardness and fracturability of traditional salt kimchi were higher than those of regular kimchi. From the sensory evaluation test for kimchi, sensory scores were high for traditional salt addition, especially taste, overall preference and texture. Among various microorganisms related to kimchi fermentation, the growth of Leuconostoc mesenteroides, Lactobacillus plantarum, Pichia membranaefaciens and Escherichia coli were examined. Based on the conditions of kimchi fermentation, a 2% and 5% concentration of each salt were studied. Also, the conditions of the cultures at $37^{\circ}C$ were examined. There was no considerable difference in the growth of Leuconostoc mesenteroides, Lactobacillus plantarum, Escherichia coli in the different kinds of salts. However, the growth of Pichia membranaefaciens was strongly inhibited by a 5% concentration of traditional salt during incubation at $37^{\circ}C$.

• Korean journal of food and cookery science
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• v.14 no.2
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• pp.195-200
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• 1998

Wheat flour and glutinous rice pastes added Kimchi were fermented at 10$^{\circ}C$ for 14 days. The numbers of total viable microorganisms and lactics were counted. Textural property by compression force and relevant changes in pectic composition were determined. Other physical properties such as color and viscosity of Kimchi juices were evaluated. Regarding the microorganism counts, the total cell counts of all Kimchi samples increased until 5th days but thereafter all decreased during fermentation. The number of lactics showed same tendency in all Kimchi samples. The compression force of control, wheat flour paste added Kimchi (WHFP-Kimchi) and glutinous rice paste added Kimchi (GLRP-Kimchi) decreased up to 72.0%, 77.0%, 66.5% respectively. During fermentation, hot water soluble pectin (HWSP) increased, whereas sodium hexametaphosphate soluble pectin (HXSP) and HCI soluble pectin (HCISP) decreased. The red chromaticity of all Kimchi juices decreased. The viscosity of all Kimchi samples decreased in the order of GLRP-Kimchi, WHFP-Kimchi and control.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.265-269
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• 2003

Gamma irradiation treatment was performed at the early and mid-fermentation stages of Kimchi preparation. Changes in fermentative microorganisms and lactate dehydrogenase activity during the fermentation periods were investigated to determine proper irradiation point for extending the shelf life of Kimchi. Initial levels of acid producing bacteria and yeast in Kimchi were 10$^4$ CFU g$^{-1}$ and 10$^1$ CFU g$^{-1}$ , and reached up to 10$^{9}$ CFU g$^{-1}$ after 15 days and 10$^{7}$ CFU g$^{-1}$ after fermentation for 30 days at 1$0^{\circ}C$, respectively. The radiation resistance of acid producing bacteria in the earlier stage (D$_{10}$ value was 0.87 kGy) was higher than at the midfermentation stage (after 10 days at 1$0^{\circ}C$, D$_{10}$ value was 0.69 kGy). Microbial growth and lactate dehydrogenase activity were inhibited significantly by gamma irradiation at the early fermentation stage of Kimchi and acidification was effectively delayed during the subsequent storage period. Although the growth of fermentative microorganisms was inhibited by gamma irradiation at the mid-fermentation stage of Kimchi, lactate dehydrogenase activity was maintained and acidification continued during the storage period.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.832-839
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• 2006

Kugija was added to Nabak kimchi to improve the quality and preservation and the optimum addition level was assessed. Kugija extract was prepared by boiling kugija fruits, at different ratios (0, 1, 3, 5, 7%; w/v) in water for 30 minutes. The changes in the physicochemical properties of the Nabak kimchi were measured during storage for 25 days at 10?, and compared to a control (without kugija). The pH was decreased in all treatments. Following the fermentation of Nabak kimchi, the total acidity values were inversely proportional the pH changes according to the nature of mutual dependence. However, in short term, during the initial 7 days of fermentation, the total acidity values decreased with increasing concentrations of kugija extract, whereas the trend was reversed after day 10. Total vitamin C content was directly proportional to the concentration of kugija extract and was decreased with the laps of fermentation. Up to day 25, 7% treatment showed the highest vitamin C content, but at 25 days 1% and 3% treatments ranked the first. The mont of reducing sugar was proportional to the concentration of kugija extract however, the difference of values between all treatments became almost indiscernible after day 25. Turbidity values were generally increased in all samples during fermentation period, although only to a limited extent. The lowest turbidity was shown at 3% treatment up to day 16. Total color difference values were increased up to day 16, but then decreased. The optimum level of kugija extract in Nabak kimchi, as determined through these experiments, was between 1 to 3% per added water content, and was preferably 3% for color and fermentation-retarding effect of the product. Kugija extract could be applied for improving the quality and preservation of traditionally prepared Nabak kimchi.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.476-482
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• 1988

The quality characteristics of pH, total acidity, and color of Kimchi juice and organoleptic properties of taste, odor and texture were studied for their changes during Kimchi fermentation. Kimchi was prepared by salting in 15% NaCl solution for 2 hours followed by addition of other spices and fermentation at $4-35^{\circ}C$. The results of pH decrease and acidity increase suggested that Kimchi fermentation can be classified into 3 steps of initial, intermediate and final stages. The activation energyes calculated from the intermediate stage where pH decreased rapidly were 15.67Kcal/mole for pH change and 18.99Kcal/mole for acidity change. The Hunter color values of Kimchi liquid showed that it becomes a weak greenish bluecolor as the fermentation progressed. Sensory characteristics of fresh sourness taste and odor and fracturability of Kimchi were increased until pH reached approx. 4.0 and then decreased while moldy taste and odor was increased rapidly thereafter.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.2
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• pp.257-262
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• 2011

The objective of this study was to investigate the changes in the microbial properties of taurine supplemented Kimchi during fermentation at $6^{\circ}C$ for 46 days. Chinese cabbage was brined in 10% salt solution for the control Kimchi and in 10% salt solution containing 1, 2 or 4% taurine (w/w, based on cabbage) for taurine supplemented Kimchi (Taurine I, II, and III groups, respectively). The pH values of all the groups dramatically decreased after 1-day of fermentation. Total numbers of viable cells were highest at 5-days of fermentation for the control, at 9-days of fermentation for Taurine I, and at 23-days of fermentation for Taurine II and III. The highest numbers of lactic acid bacteria were found at 9-days of fermentation for the control and Taurine I, and at 18-days of fermentation for Taurine II, and at 13-days of fermentation for Taurine III. The fermentation periods required to reach the highest numbers of Leuconostoc bacteria for Taurine I, II and III were longer than that for the control, suggesting that taurine might inhibit the growth of Leuconostoc bacteria during Kimchi fermentation. Based on the results obtained from the present study, it is concluded that adding taurine to the production of Kimchi could delay the ripening period of Kimchi.

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.45-50
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• 2003

The diversity and change of microbial communities during kimchi fermentation at $4^{\circ}C$ were analyzed by denaturing gradient gel electrophoresis (DGGE). Kimchi samples were taken every 5 days over the fermentation periods (for 60 days) to extract total DNA for DGGE analysis. Touchdown polymerase chain reaction was performed to amplify the V3 region of 16S rRNA gene. Sequencing results of partial 16S rDNA amplicons from DGGE profiles revealed that lactic acid bacteria (LAB), especially Weissella koreensis, Lactobacillus sakei and Leuconostoc gelidum were dominants in kimchi fermentation at $4^{\circ}C$. And we knew that W. koreensis steadily existed throughout the whole fermentation period, also Lb. sakei and Leuc. gelidum appeared from 10th day and 30th day of fermentation time, respectively and then these species were to be dominant microorganisms.