• Journal of Microbiology and Biotechnology
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• 제15권3호
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• pp.568-572
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• 2005

Saccharomyces yeast spores are more resistant to drying and storage than vegetative cells. For the mass production of yeast spores, compressed yeast was directly inoculated into a sporulation medium (SM). The effects of inoculum size and the addition of rice wine cake (RWC) into SM on the sporulation were examined using flasks. With $1\%$ inoculum of compressed yeast, $1.45{\times}10^8/ml$ of asci was obtained. The addition of $0.5\%$ RWC into SM improved the cell growth and spore yield, and the number of asci formed was $2.31{\times}10^8/ml$. The effects of culture temperature, temperature-shift, and concentrations of inoculum, potassium acetate, and RWC on the sporulation were also evaluated using a jar fermentor. The optimum temperature for spore formation was $22^{\circ}C$ where the number of asci formed was $2.46{\times}10^8/ml$. The shift of culture temperature from initial $30^{\circ}C$ for 1 day to $22^{\circ}C$ for 3 days increased the number of asci formed to $2.96{\times}10^8/ml$. The use of $2\%$ (w/v) inoculum of compressed yeast, $2\%$ potassium acetate, and $1\%$ (w/v) RWC in SM with the shift of culture temperature of initial $30^{\circ}C\;to\;22^{\circ}C$ resulted in $90\%$ sporulation ratio and formation of $6.18{\times}10^8\;asci/ml$.

• Journal of Pharmaceutical Investigation
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• 제8권2호
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• pp.1-10
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• 1978

During the course of studies on the production of glutathione from yeast, process development and optimization was carried out. The optimal pH for the extraction of glutathione was found to be 2.5 to 4.0 and the maximum yield for glutathione was obtained when the extraction temperature was 25 to $45^{\circ}C$. The cuprous salt of glutathione was recovered maximally at the range of 2 to 4g of cuprous oxide per 10 Kg of compressed yeast. Further purification was needed for the removal of impurities from glutathione. Cation exchange resin, anion exchange resin and Sephadex G-25 were employed for this purpose. 13 to 15 g of glutathione was obtained from 10 Kg of compressed yeast and the purity was above 99.3%.

• 한국식품과학회지
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• 제23권4호
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• pp.510-516
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• 1991

냉동용 yeast doughnut dough의 안정성을 향상시킬 수 있는 적정배합비를 결정하기 위하여 설탕, SSL 및 $KBrO_{3}$의 첨가량을 3 변수와 3 levels fractional factorial 설계에 의하여 RSM computer program을 사용하여 최적조건을 조사하였다. 대조구의 부피에 가장 가까운 도우넛을 생산하는데 적합한 배합은 premix에 설탕 2%, SSL 0.3%, $KBrO_{3}$ 25ppm을 첨가하는 것이었으며, 이때 compressed yeast는 premix의 7.8%를 사용하였다. 그리고 대조구의 텍스쳐에 가까운 도우넛을 생산하는데 적합한 배합은 premix에 설탕 2%, SSL 0.4%, $KBrO_{3}$ 10ppm을 첨가하는 것이었고, 전체적인 품질이 우수한 도우넛을 생산하는데 적합한 배합은 premix에 설탕 2%, SSL 0.4%, $KBrO_{3}$, 20ppm을 첨가하며, 이 때 역시 compressed yeast는 premix의 7.8%를 사용하는 것이었다. 그리고 반죽을 만들 때 floor time을 생략하는 것이 도우넛의 부피와 텍스쳐를 우수하게 유지하는데 도움이 되었다. 이와 같이 결정된 냉동용 yeast doughnut dough의 배합비에 따라 반죽을 만들어 성형한 다음 $-18^{\circ}C$에서 냉동저장하면서 저장 중 품질변화를 측정한 결과, 저장 2주까지는 도우넛의 부피와 텍스쳐가 대조구와 유사하였으나, 3주 후부터는 대구조보다 바람직하지 못하게 나타났다.

• 미생물학회지
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• 제16권3호
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• pp.93-102
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• 1978

Saccharomyces cerevisiae strain M was cultured in a molasses-containing media with repeated transplantations of the yeasts from one culture to another to adapt to molasses. After that only different amounts of phosphorous and nitrogen sources were added to the media. And then some variations during the culture time and the effects of consituents of cell mass on the functional activity and sensitivity of the cell were investigated. The results obtained were summarized as follows : 1. In the same culture condition of yeasts, the carbohydrates and trehaloses contents were more remarkably increased when small amounts of phosphate and nitrogen sources were added, then when alrge amounts were added, but yield percentage on assimilated sugars was lower. 2. The content of trehalose in yeast cells was reduced remarkably at the early stage in the culture, but this increased remarkably at later stage. When small amounts of nitrogen and phosphate were added to the culture medium, the amount of thehalose in the cells increased greasly. 3. The more protein content was present in the yeast cells, the smaller the carbohydrate and trehalose content, but more amino-N, RNA and moisture content were present in the cells. And in this case fermentability of the cells was stronger, but sugar tolerance was lower. 4. During the preservation period of compressed yeast cells at different temperature, the higher the temperature was, the more rapidly the amount of trehalose in the cells decreased. And in the cell where the amount of trehalose in the cells decreased. And in the cell where the amount of trehalose(carbohydrate) was large and the amount of protein was small, the amount of trehalose decreased at a slower rate during the preservation period.

• Current Research on Agriculture and Life Sciences
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• 제6권
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• pp.137-143
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• 1988

Straight no-time method로 조제한 냉동(冷凍)반죽을 이용(利用)한 발효(醱酵)빵제조에 있어서 가장 적절한 반죽의 조성(組成)을 제(製)빵성적(成積)을 중심으로 검토하였다. 경질(硬質)밀가루 1,000 g에 대하여 압착효모(壓搾酵母) 30 g, 설탕 50 g, 식염(食鹽) 20 g, 쇼트닝 40 g, 브롬산칼륨 75mg, L-ascorbic acid 200mg, yeast food 3 g, vital wheat gluten 30 g, 제1인산칼슘 400mg, 스테아릴젖산나트륨 8 g, 급수량(汲水量) 680 g 으로 냉동(冷凍)반죽을 만드는 것이 제(製)빵과정(過程)에서 팽창력(膨脹力)과 발효시간(醱酵時間)이 적절하고 높은 비용적(比容積)을 얻을 수 있어서 가장 바람직하였다. Farinograph 성적상의 흡수율(吸水率)보다 높은 68%의 급수량(汲水量)으로도 유화제(乳化劑)나 품질개량제(品質改良劑)의 다량첨가(多量添加)로 반죽의 동결장해(凍結障害)를 억제할 수 있었다.