• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.261-266
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• 1996

우육 지방질의 산화에 대한 김치의 항산화성과 발효기간이 다른 김치의 항산화 관련성분의 변화를 살펴본 결과는 다음과 같다. 익힌 마쇄우육(CGM)에 발효기간이 다른 김치를 조합한 모델 시스템을 $4^{\circ}C에서$ 4주간 저장하면서 산화 양상을 살펴본 결과 가열우육의 지방질 산화에 대한 김치의 항산화성은 발효기간에 따라 달랐다. 특히 발효당일의 김치나 발효 16일의 김치 보다 7일간 발효된 김치의 항산화성이 더 높은 것으로 나타났다. 그리고, 발효진행에 다른 김치의 항산화성에서도 적당히 발효된 발효 7일 전후의 김치들에서 항산화성이 높았다. 김치발효에 따른 항산화 관련 성분의 변화를 살펴 본 결과, ascorbic acid는 담금 직후 10mg%이었으나 7일간 발효한 김치는 19.43mg%로 높았다가 그 이후에는 감소하는 것으로 나타났다. $\beta-caro-tene은$ 담금 직후 0.315mg%이었으나 발효가 진행됨에 따라 감소하는 것으로 나타났으며 총 phenolic compounds는 담금 직후나 과숙 김치에서 보다 7일간 발효한 김치에서 오히려 높았다. 따라서 발효가 진행됨에 따라 김치의 항산화 작용에 기여하는 항산화 관련성분은 ascorbic acid, chlorophylls 및 phenolic compounds 등인 것으로 생각된다.

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.234-238
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• 2001

For the comparison of fermentation pattern of leek kimci with chinese cabbage kimchi, the changes of total viable cell number, Leuconostoc sp. bacteria, Lactobacillus sp. bacteria, pH and total sugar content of twotypes kimchies were investigated during fermentation at $20^{\circ}C$ and $10^{\circ}C$. In chinese cabbage kimchi at $20^{\circ}C$ fermentaion, the numbers of total viable cell, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria reachedthe maximum level on 2nd day and reduced slowly. But in leek kimchi, the maximum numbers of total via-ble cells, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria were obtained after 3 days fermentation,and the cell number of Lactobacillus sp. maintained at the maximum level oyer 15 days. At $10^{\circ}C$ fer-mentation, in both kimchies, the viable cell number of lactic acid bacteria more slowly increased anddecreased than at $20^{\circ}C$. The pH of chinese cabbage kimchi was 4.2 on 3rd day (optimal ripening phase) andmere decreased to 3.5 after 5 days, but in leek kimci the pH 4.2 could be reached after 10 days at $20^{\circ}C$. At $10^{\circ}C$, the optimal ripening pH 4.2 of chinese cabbage kimchi was reached after 6 days, but in leek kimchieven though after 24 days, the pH was maintained oyer 4.3. The total sugar contents of chinese cabbage him-chi and leek kimci were decreased continuously during fermentation. From these results, we know that thefermentation of leek kimchi proceed more slowly than chinese cabbage kimchi by the retardation of lacticacid bacteria growing in leek kimchi.

• Bulletin of Food Technology
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• v.21 no.2
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• pp.55-61
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• 2008

본 연구에서는 발효기간 중 SAM 생성량 증진김치의 최적조건을 개발하기 위해 배추김치의 재료별 및 제조법에 따른 발효기간 중의 SAM 함량 변화를 측정하였다. 발효가 진행됨에 따라 모든 김치군의 pH는 발효초기에는 급격히 감소하다가 후기에는 pH $4.2{\sim}4.3$으로 비슷하게 나타났다. 산도는 pH와 비슷한 경향을 보이면서 발효초기에는 급격히 감소하다가 후기에는 서서히 증가하는 경향을 보였다. SAM 함량은 가장 기본적인 재료로만 제조한 표준(A)김치는 가장 낮게 나타났고, SAM이 검출되는 원 부재료에 SAM 함량이 많은 김치가 SAM 함량도 높게 나타났다. 모든 김치군 중 I김치가 가장 높은 SAM 함량을 나타냈으며, 김치별 SAM 함량이 가장 높은 발효시점은 A, K김치는 pH $4.6{\sim}4.9$, 산도 $0.38{\sim}0.57$0.57, D, H김치는 pH 6.3, 산도 $0.24{\sim}0.27$, E, G김치는 pH $6.1{\sim}6.6$, 산도 $0.05{\sim}0.14$0.14, B, C, F, I, J김치는 pH $4.3{\sim}5.3$, 산도 $0.45{\sim}1.02$에서 나타났다. 따라서 대부분의 김치는 적숙기시점이 되었을 때 B, E, G, H김치는 초기발효 때부터 SAM 함량이 높게 나타났다. 또한 발효가 진행됨에 따라 SAM 함량은 감소하는 경향을 보였다. 따라서 연구결과 주재료인 채소류와 젓갈의 함량비를 적절히 제조하여 최적의 SAM 생산능력의 발효시점과 김치맛에 영향을 끼치지 않는 관능적으로 적합하고 SAM 생성이 보다 효과적으로 유도되는 최적의 조건에 대한 실험들이 추가적으로 필요하다고 판단된다.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.44-54
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• 2018

To maintain the best quality of kimchi during long-term storage, we developed a fermentation storage mode for the kimchi refrigerator. The optimal kimchi fermentation temperature was determined to be $6^{\circ}C$ with fermentation time of 4-7 days in winter and 3-5 days in spring and fall. Based on these results, the fermentation storage mode conditions were programmed to consist of a fermentation temperature of $6^{\circ}C$ and fermentation times of 111 h in winter and 58 h in spring/fall. When kimchi was stored under the developed fermentation storage mode conditions, the total acidity of kimchi was almost the same as that of the control kimchi (stored $-2-\;-1^{\circ}C$ for 12 weeks). However, the number of lactic acid bacteria (LAB) and Leuconostoc sp. in kimchi were higher ($10^1-10^2CFU/mL$) than those in the control kimchi during storage. In addition, kimchi fermented and stored under the fermentation storage mode clearly received higher scores for overall preference than the control kimchi.

• Korean journal of food and cookery science
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• v.8 no.4
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• pp.365-369
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• 1992

To investigate the effect of onion on kimchi fermentation, the changes on the pH, total acidity and total sugar content of kimchi with the addition of different amouts (5%, 10% and 15%) of onion were measured and the odor and taste evaluation was conducted during fermentation at $14^{\circ}C$ for 20 days. As the fermentation period increased, fermentation rate of kimchi contained onion was higher in 5% onion and was lower in 10% and 15% onion than that of control kimchi, sensory evaluation score of onion kimchi was lower in 5% onion and higher in 10% and 15% onion than that of control kimchi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1009-1015
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• 2000

Fermentative and antioxidative characteristics of red mustard leaf (RML) kimchi, a traditional, fermented Korean vegetable food, were investigated. For the study, RML kimchi was made of RML, with green onion, red pepper, garlic, ginger, and sugar, and fermented at 15$^{\circ}C$. The pH was decreased and total acidity was increased during fermentation. The contents of reducing sugar, total vitamin C, and total Phenol content were 2.36%, 65 mg%, and 59 mg% at the initial stage. Although the content of reducing sugar decreased gradually during fermentation, however, the quantity of ascorbic acid decreased with the tendency of slightly increased at 6 days, and the amount of total phenol was increased. CIE L*, a*, b＊values were increased until 6 days of the fermentation. In order to determine the antioxidative activity of RML kimchi itself, the model systems of RML kimchi were made with cooked beef. TBA values of RML kimchi which was fermented for 6 days showed the lowest level in model systems. Water, n-hexane, methanol extracts of RML kimchi had a considerable antioxidative activity with the inhibition of formation of peroxide during the autoxidation of linoleic acid mixtures in aqueous model systems.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.742-749
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• 2009

In order to establish the basic scientific data on the fermentation characteristics of chonggak kimchi (CGK), we studied with CGKs prepared at different seasons and stored at various temperatures ($5{\sim}23^{\circ}C$). Changes in pH and acidity of CGK fermented at different temperatures were typical. However, acidity of summer CGK stored under $15^{\circ}C$ did not reach 1.0% since the amount of reducing sugar in the summer radish was lower by over 1% than the ones from the other seasons. Growths for Leuconostoc and Lactobacillus spp. over 8.0 logCFU/mL were observed in CGKs fermented above $10^{\circ}C$. Changes in Max G, cutting force, of CGK from different seasons were apparent. Max Gs for spring and summer CGK were decreased immediately right after storage while Max Gs for winter CGKs were increased slowly during storage. According to the results of sensory evaluation, CGKs revealed the highest overall acceptability when acidity of kimchi reached $0.7{\pm}0.1%$ under the given fermentation condition. However, CGK prepared with radish from winter or summer season tasted better than the one made in the spring. But the edible periods for winter CGKs were longer, compared with summer CGKs fermented at the same temperature. In conclusion, CGK fermented at $10^{\circ}C$ in the winter season gives a better taste with longer edible duration than the other CGKs.

• Food Science and Preservation
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• v.18 no.5
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• pp.786-794
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• 2011

To investigate the sanitary-quality level of commercial kimchi in South Korea, the pH, acidity, and microbial-flora changes in the kimchi were determined. Samples of kimchi produced by three different manufacturers (a small grocery store, a small/medium-sized enterprise, and a large food company) were collected. Freshly made kimchi was purchased and fermented at $10^{\circ}C$ for 10 days. The pH of the commercial kimchi on the purchased day was approximately pH 5.8, and that on the $10^{th}$ day of fermentation was ${\simeq}pH$ 4.1. The kimchi purchased from a large company showed a more rapid decline in pH level during fermentation. The saltiness of the kimchi purchased from a medium-sized company was slightly higher than those of the other commercial kimchi samples. The saccharinity index of the kimchi produced by a small grocery store was higher than those of the other samples, and its value deviation was also higher than those of the other commercial kimchi samples. A higher total viable-cell count and a higher lactic-acid bacteria (LAB) count were detected in the kimchi from the large food company at the beginning of fermentation compared to the samples of the two other kimchi manufacturers. The highest cell numbers of gram-positive bacteria (except LAB) and coliform bacteria were detected from the small-grocery-store kimchi, but the coliform bacteria count gradually decreased during fermentation although such bacteria were still detected until the $10^{th}$ day of fermentation. In contrast, coliform bacteria were not detected in the samples from the medium-sized and large food companies. Yeast, which is detected in over-ripened kimchi, was detected in the unfermented kimchi from the small grocery store, which had a below-0.36% acidity level. The gram-positive bacteria (except LAB) that were detected in all the tested commercial kimchi samples were determined to be Bacillus spp., and the gram-negative bacteria were determined to be Escherichia coli, Enterobacter spp., Sphingomonase spp., and Strenophomonas spp. The proportions of all the aforementioned bacteria in the kimchi samples, however, were different depending on the samples that were taken. These results indicate that a more sanitary kimchi production process and a more systematic kimchi production manual should be developed to industrialize and globalize kimchi.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.784-789
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• 1997

The difference of quality characteristics between whole Chinese cabbage kimchi (pogi kimchi) and sliced Chinese cabbage kimchi (mat kimchi) was examined during fermentation at $20^{\circ}C\;and\;5^{\circ}C$. Pogi kimchi showed a delayed fermentation about 2 days at $20^{\circ}C$ and 10 days at $5^{\circ}C$. L (lightness), a (redness) and b (yellowness) of pogi and mat kimchi gradually increased during fermentation. These values were revealed slightly higher for mat kimchi at $20^{\circ}C\;than\;at\;5^{\circ}C$. $CO_{2}$ concentration within package steeply increased for both types of kimchi in 3 days, but $O_{2}$ concentration was decreased until that time. The number of lactic acid bacteria of mat kimchi was generally higher than that of pogi kimchi at $20^{\circ}C$, but pogi kimchi showed higher lactic acid bacteria at $5^{\circ}C$. Smell, color and taste of kimchi fermented at $20^{\circ}C$ was better than those of kimchi fermented at $5^{\circ}C$, but there were no great differences between pogi kimchi and mat kimchi.