• 한국식품영양과학회지
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• 제26권5호
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• pp.788-793
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• 1997

Addition of sugar, enzymatic hydrolysis and salt concentration were evaluated for their effects on the changes in some characteristics of Kimchi juice during fermentation. The Kimchi juice was prepared by brining and grinding of outer layer leaves of chinese cabbage, one of the wastes products of Kimchi processing, followed by fermentation proceeded significantly faster. Addition of sucrose or glucose at the ange of 0.5~2.0 % also improved the fermentation but the concentration effect was little. Enzymatic hydrolysis on the brined cabbage prior to fermentation with a commercial polysaccharides hydrolases also increased the fermentation. However the solid concentration in Kimchi juice was rather decreased by higher concentration of NaCl and enzymatic hydrolysis. The reducing sugar content showed a rapid decrease from 24 hours of fermentation and the effect of enzymatic hydrolysis was little.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.531-537
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• 1994

This study was undertaken with objective of optimizing the conditions of fermentation in an aqueous two-phase system which is composed of polyethylene glycol (PEG) 20000 and crude dextran (Dx). The data were obtained and analyzed using the Box-Wilson's experimental design protocol and the response surface methodology. To reach this end a multilinear polynomial regres- sion model was developed, which can be utilized for the purpose of optimizing the extractive fermentation. Optimum conditions for batch fermentation with aqueous two phase system were found to be at 4.2~5.4% PEG/3.2~4.2% Dx range. The composition of the center was 4.8% PEG/ 3.6% Dx. Optimum operating conditions for initial sugar concentration and fermentation time were approximately 160 g/l, and 21~22 hr, respectively. Fermentation in the aqueous two phase system composed of 5% PEG/4% Dx showed increase of 23% in ethanol concentration, of 9.5% in ethanol yield, and of 19% in ethanol productivity as compared to the case of fermentation of neat Jerusalem artichoke juice.

• 한국식품저장유통학회지
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• 제7권1호
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• pp.89-93
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• 2000

The study was conducted to investigate the characteristics of peach vinegar by parallel-complex fermentations. The vinegars prepared by using Changbnag-Chosang and Yumung peach cultivars added with 7, 10, and 13% sugaring concentrations were examined. The rate of increase in alcohol degree and titratable acidity, and that of decrease in soluble solids showed higher at Yumyung peach than at Changbang-chosang. Alcohol and acetic acid fermentation by paralle-complex fermentation were performed better in Yumyung peach than Changbang -chosang. but the fermentation of Yumyung showed active alcohol fermentation in the early stage, and active acetic acetic acid fermentation in the late stage. Quality of the vinegar prepared with Yumyung peach was better than that of Changbang-chosang, which were evaluated by acetic acid contents , peach taste and odor in the vinegar, and overall taste. The fermentation was accelerated with an increase in sugaring , concentrating but overall taste was best in 10 % sugaring.

• 동아시아식생활학회지
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• 제5권3호
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• pp.287-298
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• 1995

This study was undertaken to examine the effect of salting in 10% salt solution added 2% calcium chloride on the kimchi fermentation. The addition of calcium chloride extended edible periods of the Kimchi to 4~5 days and increased relatively the hardness of Chinese Cabbage. In the addition of calcium chloride, the activities of amylase and $\beta$ -galactosidase were not high during all periods fermentation. Polygalacturonase and protease activities were low 2~21%, 2~26% all periods fermentation, respectively. There were significant correlations between the delay of ripeness and decreasing enzyme activation. The amount of free amino acid by the treatment with calcium chloride was decreased of 10~16% at the late of fermentation than that of control. the treatment with calcium chloride of the Kimchi was increased hardness, but decreased cohesiveness and gumminess was during all periods fermentation. the adhesiveness was increased at the early of fermentation but decreased at the late of fermentation.

• 한국식품영양과학회지
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• 제33권10호
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• pp.1703-1708
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• 2004

전통증편에 영양강화와 이용도를 확대시킬 목적으로 눈꽃 동충하초 증편을 제조하여 발효시간별 품질특성을 조사하였다. 발효시간을 달리 하여 제조한 동충하초 첨가 증편의 반죽의 부피변화는 발효전보다 발효 3시간과 2차 발효 30분의 부피가 더 증가하였으며 발효가 더욱 진행될수록 부피는 감소하였다. pH는 발효 전 pH 5.1로 발효가 진행될수록 감소하였으며 수분은 발효시간이 길어질수록 증가하였다 색도는 명도와 황색도는 1차 발효 후의 증편이 가장 높았으며 발효시간이 길어질수록 낮았다. 기계적 texture측정에서 견고성은 2차 발효 90분 후의 증편이 가장 높았으며 껌성과 부서짐성도 발효시간이 경과할수록 높아지는 경향을 보였다. 주사전자현미경 의 표면구조 관찰에서는 2차 발효 시간이 길어질수록 스폰지상의 조직이 파괴되어 기공이 뚜렷하게 나타나지 않았다. 관능검사에서 색의 강도는 2차 발효가 진행될수록 색의 강도가 강하다고 평가하였으며 단단한 정도, 질긴 정도, 쓴맛은 발효시 간이 길어질수록 높게 나타났다. 전반적인 기호도는 1차 발효만을 실시한 증편과 30분동안 2차 발효를 한 증편이 가장 좋은 선호도를 보여 동충하초 첨가 증편의 발효시간은 3$0^{\circ}C$에서 1차 발효 3시간 후와 35$^{\circ}C$에서 2차 발효 30분이 최적 발효조건임을 확인할 수 있었다.

• 한국균학회지
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• 제31권1호
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• pp.28-33
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• 2003

설탕을 이용한 고부가가치의 버섯 발효식품 제조시 최적 발효기간을 설정하기 위하여 발효기간의 경과에 따른 버섯 발효액의 품질특성과 효소활성 및 생리기능성의 변화를 조사하였다. 점도와 색상을 나타내는 L값, a값, b값 모두 3개월까지 급격히 감소한 후 증가하는 경향이었다. 관능특성은 발효기간이 증가함에 따라 고유의 냄새와 맛은 감소하고, 다른 맛과 냄새는 증가하는 경향이었으며, 전체적인 기호도는 발효 3개월 버섯 발효액이 제일 좋은 것으로 평가되었다. 버섯 발효액 중의 ${\alpha}-amylase$ 활성은 발효 1개월까지 급격히 증가하였고, invertase와 cellulose는 대부분 활성이 낮거나 없었다. 항산화할성은 발효 4개월에 가장 높았고 그 이후에는 약간 감소하는 경향이었으며 tyrosinase 저해활성은 모든 시료에서 높은 활성을 나타내었고, 발효기간의 경과에 따라 변화가 없었다. SOD 유사활성은 팽이버섯 발효액에서 비교적 높은 활성을 나타내었으며, 발효기간에 따라서는 큰 변화가 없었다. 이상의 결과를 종합해 볼 때 설탕을 이용한 버섯 발효액 재품 생산시 최적 발효기간은 3-4개월 정도가 적합할 것으로 판단된다.

• 한국식품과학회지
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• 제35권2호
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• pp.272-279
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• 2003

산야채를 이용하여 추출물 발효식품을 제조하는데 있어서 적합한 발효기간을 설정하기 위하여 발효기간의 경과에 따른 발효액의 성분과 품질특성, 효소활성과 생리기능성의 변화를 조사하였다. 발효기간이 경과함에 따라 pH와 $^{\circ}Bx$는 점차 낮아졌으며, 점도는 감잎 추출물 발효액을 제외하고는 3개월 경과시 현저히 낮아졌다. 색도는 발효기간이 증가함에 다라 L값과 a값은 증가되고, b값은 감소되는 경향이었다. 발효액 중의 amylase 효소활성은 발효 6개월이 경과하면서 발효 전에 비하여 $167{\sim}800%$ 수준으로 증가하였고, invertase는 발효 초기에는 활성이 거의 없었으나 1개월 경과시에 $60{\sim}170$ units의 약한 활성을 나타내었으며, cellulase는 거의 활성을 나타내지 않았다. 총 페놀함량과 항산화활성도는 발효가 진행됨에 따라 증가하여 $3{\sim}4$개월시 가장 높았고, 그 이후에는 감소하는 경향이었다. Tyrosinase 저해활성은 쑥을 제외한 모든 발효액에서 활성을 나타내었으며, 발효기간에 따라 큰 변화가 없었다. SOD 유사활성은 아카시아와 감잎 발효액에서 각각 $23.1{\sim}25.1%,\;26.8{\sim}29.2%$의 약한 활성을 나타내었으며, 발효 기간에 따라 큰 변화가 없었다. 관능적인 특성을 조사하였을 때 쑥은 발효 기간에 따라 큰 차이가 없었고, 솔잎은 발효기간이 증가되면서 맛과 냄새의 강도가 높아졌으며, 전체적인 기호도가 발효 3개월에서 가장 좋은 것으로 평가되었다. 이상의 결과를 종합해 볼 때 산야채 추출물의 발효기간은 $3{\sim}4$개월 정도가 적합할 것으로 판단된다.

• 한국식품저장유통학회지
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• 제6권2호
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• pp.228-232
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• 1999

단감과 떫은감을 이용하여 알콜발효 및 초산발효의 2단계 발효에 의하여 감식초 제조과정 중 성분변화를 조사하였다. 발효됨에 따라 총산 함량은 점차 증가하여 초산 발효 8일째에 단감과 떫은감에서 각각 5.95, 5.81%이었다. 색상은 알콜발효 및 초산발효 중 L값과 b값은 떫은감에서, a값은 단감에서 각각 높게 나타났다. 갈색도는 알콜 발효기간이 지남에 따라 점차 증가하였으나 초산발효에서는 갈색도 및 탁도가 점차적으로 감소하여 갈색도는 단감에서, 탁도는 떫은감에서 각각 높게 나타났다. 총탄닌 함량은 초기에 단감 및 떫은감에서 각각 2.40과 6.44mg/ml이었으나 발효기간이 지남에 따라 점차 감소하여 초산발효 8일 후에는 각각 1.06 및 3.82mg/ml이었다. 환원당과 총당은 발효기간이 경과함에 따라 점차 감소하여 초산발효 5일째에 단감에서 각각 5.0 및 8.5mg/ml이었고, 떫은감에서 각각 2.8 및 2.9mg/ml이였으며 그 이후에는 큰 변화가 없었다.

• Journal of Microbiology and Biotechnology
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• 제4권3호
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• pp.222-229
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• 1994

In order to develop a method of economical production and to reduce energy-consumption in fuel alcohol production, we investigated the fermentation characters of two newly selected thermotolerant yeasts. The RA-74-2 showed stable and superior fermentability between 30 and $40^{\circ}C$ in 20% glucose media in comparison to the industrial strains. The optimum concentration of glucose for economical fermentation at $40^{\circ}C$ was 15-18%, and organic nitrogen was necessary for a satisfactory fermentation. The optimum pH was 4.0 and aeration was adversed for high temperature fermentation. Agitation was an important factor at $40^{\circ}C$ and the addition of magnesium ion 0.2% was required in this experiment. When the inoculum was increased, ethanol productivity as well as the speed of fermentation increased. On the other hand RA-912, which can grow at $48^{\circ}C$, showed similar fermentability between 30-$45^{\circ}C$ in 20% glucose media As the concentration of substrate decreased, fermentation ratio increased at $45^{\circ}C$ (45%, 65%, 95% fermentation ratio in 20%, 15%, 10% glucose media, respectively). Also, requirement of organic nitrogen and magnesium ion in RA-912 was similar in RA-74-2. The optimum pH for fermentation was 5.0, and the effects of agitation were enhanced at $37^{\circ}C$ than at $45^{\circ}C$. As the inoculum was increased, fermentation speed became more enhanced but the ethanol productivity was less affected. RA-912 showed fermentability with various substrates. Among the substrates used, inulin was the most promising substrate for the high-temperature fermentation. When 14.5% inulin was used as the substrate, 93% and 55% fermentation ratios were shown at $37^{\circ}C$ and $45^{\circ}C$, respectively.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1195-1206
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• 2020

Beringraja pulchra, Cham-hong-eo in Korean, is a mottled skate which is belonging to the cartilaginous fish. Although this species is economically valuable in South Korea as an alkaline-fermented food, there are few microbial studies on such fermentation. Here, we analyzed microbial changes and pH before, during, and after fermentation and examined the effect of inoculation by a skin microbiota mixture on the skate fermentation (control vs. treatment). To analyze microbial community, the V4 regions of bacterial 16S rRNA genes from the skates were amplified, sequenced and analyzed. During the skate fermentation, pH and total number of marine bacteria increased in both groups, while microbial diversity decreased after fermentation. Pseudomonas, which was predominant in the initial skate, declined by fermentation (Day 0: 11.39 ± 5.52%; Day 20: 0.61 ± 0.9%), while the abundance of Pseudoalteromonas increased dramatically (Day 0: 1.42 ± 0.41%; Day 20: 64.92 ± 24.15%). From our co-occurrence analysis, the Pseudoalteromonas was positively correlated with Aerococcaceae (r = 0.638) and Moraxella (r = 0.474), which also increased with fermentation, and negatively correlated with Pseudomonas (r = -0.847) during fermentation. There are no critically significant differences between control and treatment. These results revealed that the alkaline fermentation of skates dramatically changed the microbiota, but the initial inoculation by a skin microbiota mixture didn't show critical changes in the final microbial community. Our results extended understanding of microbial interactions and provided the new insights of microbial changes during alkaline fermentation.