• 한국환경보건학회지
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• 제34권1호
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• pp.70-75
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• 2008

The Chinese cabbage kimchi, baechoo-kimchi, is the most popular type of kimchi in Korea. This study was performed to investigate the changes of index microorganisms (aerobic bacteria, psychrotrophilic bacteria, coliforms, and Escherichia coli), lactic acid bacteria, pH, and acidity of kimchi during the long-term fermentation and ripening. A homemade-style traditional Korean baechoo-kimchi, was prepared from Chinese cabbage, red pepper, green onion, garlic, ginger, and salt-fermented anchovy sauce, and then incubated at $10^{\circ}C$ for 28 days. In the baechoo-kimchi, the number of aerobic bacteria increased with time. The number of psychrotrophilic bacteria maintained their numbers $(10^4CFU/g)$ in the kimchi during the fermentation. Coliforms and E. coli were not detected in the kimchi. The pH of kimchi decreased and the acidity of kimchi increased over time. Lactic acid bacteria, which are representative of fermentative microorganisms in the kimchi process showed rapid growth in the earlier stage of fermentation and increased steadily after 7 days. The counts of lactic acid bacteria were at a level of $10^4CFU/g$ early in the fermentation stage, reaching a level of $10^8CFU/g$ after 14 days, and at this point pH was 4.18 and acidity reached 0.63, indicating that the optimal state of kimchi fermentation. This study suggests that the lactic acid bacteria which were proliferated in kimchi during the ripening and fermentation could contribute to improving the taste and flavor of kimchi and inhibit the growth of pathogenic microorganisms that might exist in kimchi.

• 한국미생물·생명공학회지
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• 제6권1호
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• pp.17-22
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• 1978

돈분과 옥분을 50：50으로 혼합하여 3$0^{\circ}C$에서 발효시킬때 초기에는 fecal streptococci가 많이 출현하나 이후 lactobacilli가 발효의 주역을 담당하고 7일 후에는 L. acidophilus, L. fermenti와 L. delbrueckii가 함께 성장하였다. 탈효과정중 젖산균에 의한 산생성으로 인하여 pH가 4.2까지 감소하였으며, E. coli와 효모가 1~2일만에 검출되지 않았으므로 다른 유해 미생물의 생육 억제도 생각할 수 있게 되었다. 또한 옥분내의 풍부한 영양 성분과 발향물의 분취가 산취로 대체됨으로써 풍미가 가축기호에 적당하게 되고 가축분의 이용시 본 시험에서 사용한 방법을 이용함으로써 생돈분의 가열멸균이 아닌 유산균의 자연발효를 통하여 돈분을 사료화시킬 수 있음을 보여주고 있다.

• 한국축산식품학회지
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• 제33권6호
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• pp.744-751
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• 2013

The objective of this study was to assess the physicochemical and sensory changes of a kefir manufactured by a two-step fermentation (MTY, $1^{st}$ step: $37^{\circ}C$ for 9 h; $2^{nd}$ step: $24^{\circ}C$ for 15 h) and compare it with kefirs produced by two conventional methods (GTY, fermentation at $37^{\circ}C$ for 24 h; KEY, $22^{\circ}C$ for 24 h). Rapid changes in pH and titratable acidity (TA) were observed in samples from all three manufacturing methods during fermentation process and storage period. Lactic acid bacteria (LAB) counts of MTY increased gradually up to 12 h of fermentation, reaching 9.28 Log CFU/mL, with maximum value observed in this experiment of 9.48 Log CFU/mL. The LAB counts of all samples decreased significantly during storage. The highest viscosity was observed for MTY (1750-1771 cPs), compared with the lowest viscosity observed for KEY (1250-1277 cPs). The viscosity of all samples increased slightly during storage (1250-1805 cPs, p<0.05), as well as carbon dioxide content (0.01-1.36%, p<0.05), except for GTY. The most significant increase in alcohol concentration during storage period was seen in MTY from 0.01% to 1.36% (p<0.05). MTY scored significantly higher in most items of the sensory analysis, indicating that the product manufactured by the two-step fermentation method is more acceptable compared with conventionally produced kefirs.

• 한국식품저장유통학회지
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• 제8권4호
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• pp.449-455
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• 2001

키위와 무를 첨가하여 42$^{\circ}C$에서 72시간동안 발효시킨 검정콩 청국장의 pH, 총산, 환원당, 질소화합물 및 무기질 함량을 조사하였다. 검정콩 청국장의 발효중 pH는 증가하였고, 총산은 감소하였으며, 키위를 첨가한 검정콩 청국장을 제외한 시료구 모두 24시간 이후로 급격한 변화를 나타내었다. 환원당은 24시간을 전후하여 증가하다가 감소하였고, 검정콩 청국장은 가장 함량이 많았으며, 나머지 청국장은 비슷하였다. 아미노태 질소는 발효 24시간 이후부터 급격히 증가하였으며, 키위와 무를 첨가하므로 검정콩 단백질의 분해율을 증진시켜 대두 청국장과 비슷한 함량을 나타내었다. 암모니아태 질소는 72시간 이상 발효할 때에는 검정콩 청국장이 대두 청국장에 비하여 적은 함량을 나타내었다. 무기질은 K가 가장 많았고, 다음으로 P > Mg > Ca순으로 많았으며, 대체로 검정콩 청국장류가 대두 청국장보다 비슷하거나 약간 많았다.

• Rapid Communication in Photoscience
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• 제2권1호
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• pp.28-30
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• 2013

The extract of Punica granatum peel was separated and confirmed by HPLC, and punicalagin, one of the extract, was better antibacterial activity against Salmonella.

• 한국식품영양과학회지
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• 제38권12호
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• pp.1811-1814
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• 2009

귀리추출물에 L. delbrueckii subsp. bulgaricus 또는 S. salivarius subsp. thermophilus를 단일균주로 발효한 것에 비하여 L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus를 혼합하여 발효하는 경우에는 미생물균수와 산 생성이 증가하였다. pH의 변화에서도 S. salivarius subsp. thermophilus의 경우가 L. delbrueckii subsp. bulgaricus보다 더 낮은 pH를 나타내었으며, L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus를 혼합하여 발효하는 경우에는 pH가 더 빠르게 감소하였다. 이러한 결과는 우유를 원료로 한 요구르트의 경우처럼 귀리추출물의 젖산발효에서도 L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus의 두 균주 간에 생육촉진 현상이 있음을 의미하는 결과로 해석될 수 있는데 그 정도는 매우 적었다. 본 실험에서 S. salivarius subsp. thermophilus의 미생물균수와 산 생성이 더 증가한 반면 pH는 더 낮은 이유는 L. delbrueckii subsp. bulgaricus에 비하여 귀리추출물에 더 잘 적응하였기 때문이라고 생각된다.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.569-573
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• 2010

A quantitative detection method for Salmonella in seafood was developed using a SYBR Green-based real-time PCR assay. The assay was developed using pure Salmonella DNA at different dilution levels [i.e., 1,000 to 2 genome equivalents (GE)]. The sensitivity of the real-time assay for Salmonella in seeded seafood samples was determined, and the minimum detection level was 20 CFU/g, whereas a detection level of 2 CFU/ml was obtained for pure culture in water with an efficiency of ${\geq}85%$. The real-time assay was evaluated in repeated experiments with seeded seafood samples and the regression coefficient ($R^2$) values were calculated. The performance of the real-time assay was further assessed with naturally contaminated seafood samples, where 4 out of 9 seafood samples tested positive for Salmonella and harbored cells <100 GE/g, which were not detected by direct plating on Salmonella Chromagar media. Thus, the method developed here will be useful for the rapid quantification of Salmonella in seafood, as the assay can be completed within 2-3 h. In addition, with the ability to detect a low number of Salmonella cells in seafood, this proposed method can be used to generate quantitative data on Salmonella in seafood, facilitating the implementation of control measures for Salmonella contamination in seafood at harvest and post-harvest levels.

• 한국식품영양학회지
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• 제12권1호
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• pp.77-84
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• 1999

The purpose of this study is to establish a rapid preparation method of Dongchimi-juice having favor-able flavor and high antibacterial activity against undesirable bacteria in Naengmyon-broth by using high antibacterial strains of lactic acid bacteria Lactobacillus homohiochii B21 and leuconostoc mesenteroid-es subsp. mesenteroides C16 as Dongchimi starter. When the two strains of lactic acid bacteria were used as starter mixed culture was better than single culture in acid production and antibacterial activity. When starter was not inoculated in Dongchimi fermentation the numbers of Gram negatives and colifor-ms were remarkably increased in early phase and antibacterial activity could scarcely be detected. But when starter was inoculated the numbers of Gram negatives and coliforms were sharply decreased from early phase and antibacterial ctivity was high. When Dongchimi was made with heat sterilized mat-erials and starter there were no Gram negatives and coliforms and antibacterial activity was high. The antibacterial activity of starter inoculated Dongchimi was maximum in 2 days of fermentation at 2$0^{\circ}C$ and was scarcely detected in six days. In consideration of coliform counts antibacterial activity and the flavor of Dongchimi the preparation method in which all materials were heat treated at 8$0^{\circ}C$ for 15 min-utes and inoculated with mixed starter of the two strains and fermented for 2 days at 2$0^{\circ}C$ was thoug-ht to be good.

• Asian-Australasian Journal of Animal Sciences
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• 제27권7호
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• pp.937-945
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• 2014

Green and black tea by-products, obtained from ready-made tea industry, were ensiled at $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$. Green tea by-product silage (GTS) and black tea by-product silage (BTS) were opened at 5, 10, 45 days after ensiling. Fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (PEG) as a tannin-binding agent. Results showed that the GTS and BTS silages were stable and fermented slightly when ensiled at $10^{\circ}C$. The GTS stored at $20^{\circ}C$ and $30^{\circ}C$ showed rapid pH decline and high acetic acid concentration. The BTS was fermented gradually with moderate change of pH and acid concentration. Acetic acid was the main acid product of fermentation in both GTS and BTS. The contents of total extractable phenolics and total extractable tannins in both silages were unaffected by storage temperatures, but condensed tannins in GTS were less when stored at high temperature. The GTS showed no PEG response on in vitro gas production, and revealed only a small increase by PEG on $NH_3$-N concentration. Storage temperature of GTS did not affect the extent of PEG response to both gas production and $NH_3$-N concentration. On the other hand, addition of PEG on BTS markedly increased both the gas production and $NH_3$-N concentration at any ensiled temperature. It can be concluded that tannins in both GTS and BTS suppressed rumen fermentation, and tannins in GTS did more weakly than that in BTS. Ensiling temperature for both tea by-products did not affect the tannin's activity in the rumen.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.166-171
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• 2002

The genus Leuconostoc is generally recognized as a favorable microorganism associated with a good taste of Kimchi and Lactobacillus plantarum is responsible for the overripening and acidification of Kimchi. A rapid and reliable PCR-based method to monitor the change of these lactic acid bacterial populations during Kimchi fermentation was attempted. A Leuconostoc-specific primer set was chosen from the conserved sequences of 16S rRNA genes among Leuconostoc species. The Lb. plantarum-specific primer set was the internal segments of a Lb. plantarum-specific probe which was isolated after randomly amplified polymorphic DNA (RAPD) analysis and tested for identification. The specificity of this protocol was examined in DNA samples isolated from a single strain. In agarose gel, as little as 10 pg of template DNA could be used to visualize the PCR products, and quantitative determination was possible at the levels of 10 pg to 100 ng template DNA. For the semi-quantitative determination of microbial changes during Kimchi fermentation, total DNAs from the 2 h-cultured microflora of Kimchi were extracted for 16 days and equal amounts of DNA templates were used for PCR. The intensities of DNA bands obtained from PCR using Leuconostoc-specific and Lb. plantarum-specific primer sets marked a dramatic contrast at the 1 ng and 100 ng template DNA levels during Kimchi fermentation, respectively. As the fermentation proceeded, the intensity of the band for Leuconostoc species increased sharply until the 5th day and the levels was maintained until the 11 th day. The sharp increase for Lb. plantarum occurred after 11 days with the decrease of Leuconostoc species. The results of this study indicate that Leuconostoc species were the major microorganisms at the beginning of Kimchi fermentation and reach their highest population during the optimum ripening period of Kimchi.