• 한국미생물·생명공학회지
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• 제24권4호
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• pp.512-518
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• 1996

Eleven strains had been previously isolated from kimchi and identified in our laboratory. The ability of each strain in aroma production was investigated by sensory evaluation. Among them Saccharomyc s sp. YK-17, Saccharomyces sp. YK-18, Saccharomyces sp. YH-3 and Saccharomyces fermentati YK-19 produced fruity flavour. Especially, Saccharomyces fermentati YK-19 produced apple and pineapple-like flavours. Pichia media YK-11, Saccharomyces sp. YK-20 and Pichia chambardii YH-4 produced wine-like flavour. Debaryomyces sp. YK-6, Debarymyces coudertii YK-10, Saccharomyces sp. YK-12 and Pichia haplophilia YH-5 produced alcoholic flavours. Using the good flavour producing strains as starters, various groups of kimchi were fermented, and the sensory characteristics of each group such as odor, taste and total acceptability were evaluated. The acidic odor, moldy odor and taste were reduced by adding starter, while the fresh sourness odor and taste similar to fruity fiavour were increased by starter. Comparing with the control group, these odor, taste and total acceptability were increased in the starter-added groups, such as Pichia edia YK-11, Saccharomyces sp. YK-17, and Saccharomyces,fermentati YK- 19. Saccharomyces fermentati YK-19 added kimchi group was higher siginificantly (P<0.05) than the others at the total acceptability. Volatile compounds of the culture broth of Saccharomyces fermentati YK-19 were analysed by gas chromatography, and 6 species of esters and 4 species of alcohols were identified. Among them, the ester substances which broth largely responsible for the apple-like flavour in the sensory evaluation, were found to be ethyl 2-methyl butvrate, ethyl pentanoate and ethyl acetate.

• 한국식품과학회지
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• 제29권4호
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• pp.790-799
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• 1997

Lactic acid와 acetic acid를 탄소원으로 이용할 수 있으며, 혐기적 상태에서 생육 가능하고 저온성, 내염성, 내산성의 성질을 가지며 뛰어난 방향성을 갖는, 김치로부터 분리된 효모, 즉 Saccharomyces sp. YK-17 균주와 Saccharomyces fermentati YK-19 균주를 starter로 첨가하여 발효시켰을 때 김치의 이화학적 성분과 미생물의 경시적인 변화, 그리고 관능적 특성을 비교 평가하였다. Starter 첨가군 김치가 대조군보다 전 발효기간 동안 산생성량이 낮았고, 특히 S. fermentati YK-19 균주를 starter로 첨가할 경우 김치 적숙기(pH 4.0, 산도 $0.6{\sim}0.8%$)를 대조군보다 약 1.63배 연장시킬 수 있었다. 비휘발성 유기산의 변화는 발효가 진행됨에 따라 lactic acid가 가장 많이 생성되었으며, 초기에 1.71 mg/100g이던 것이 발효 30일째에는 대조군이 77.60 mg/100g으로, S. sp. YK-17 첨가군은 69.24 mg/100g으로, 그리고 S. fermentati YK-19 첨가군은 45.22 mg/100g으로 3실험군 중에서 YK-19첨가군이 가장 낮았다. 그리고 김치산패의 주 원인균으로 알려져 있는 젖산균인 Lactobacillus속 균주의 성장이 starter첨가 김치, 특히 S. fermentati YK-19 첨가 김치에서 현저하게 억제되었다. 또한 starter 균주의 산 이용성 및 우수한 방향 생성능으로 인해 starter 첨가군에서 신맛과 신내를 덜 느끼고 아울러 과실향에 유사한 향미가 김치에 부여됨으로써 대조군보다 기호도가 훨씬 높은 김치를 제조할 수 있었다.

• 한국미생물·생명공학회지
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• 제24권4호
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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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• 제9권1호
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• pp.22-31
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• 1999

Saccharomyces fermentati and Leuconostoc mesenteroides were isolated from a traditional kimchi, and then the Leu. mesenteroides was mutated to the acid-tolerant mutant Leu. mesenteroides M-l00. In the result of growth properties in MRS broth with various pHs adjusted with HCl and acid solution (latic acid:acetic acid=1:2), an acid-tolerant mutant Leu. mesenteroides M-100 showed more increased ability for growth than its wild strain at various temperatures. The strains were used as starters for the fermentation of kimchi. The experiments were performed with classified experimental groups (Group I, control kimchi; Group II, addition of YK-19 only; Group III, addition of M-100 only; Group IV, addition of mixture of M-100 and YK-19), and their pH, total acidity, reducing sugars content, organic acid productivity, organoleptic tests, and microfloral changes were compared. As a result, in pH and acidity, the optimal ripening period of Group IV was about 13.5 days (i.e. from the 8.5 to 22 days of fermentation). This result indicates that the optimal ripening period of Group IV was about 1.5 times longer than that of Group I. Furthermore, Group IV was edible to 28 days of fermentation. In addition, high contents of succinc acid was observed in Group IV. Group IV was also highly ranked on the organoleptic test. During the fermentation of kimchi, the number of Leuconostoc sp. in group I reduced after 7 days; however, the number of Leuconostoc sp. in Group II, III, and IV decresed after 14 days of fermentation. An especially high number of Leu. sp. was observed in Group IV, and this gave better flavor of kimchi than any other during the whole fermentation period. Citric acid, tartaric acid, succinic acid, fumaric acid, and lactic acid were detected in the kimchi, and a significant increase in the concentration of lactic acid during fermentation was observed in the all experimental groups.