• 한국미생물·생명공학회지
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• 제51권2호
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• pp.184-190
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• 2023

Bioethanol has recently attracted much attention as a sustainable and environmentally friendly alternative energy source. This study aimed to develop a potential process for bioethanol production by fed-batch fermentation using instant dry yeast. To obtain the highest cell growth, we studied the influence of the initial sugar concentrations and pH of sugarcane molasses in batch fermentation. The batch system employed three levels of sugar concentrations, viz. 10%, 15%, 20% (w/v), and two levels of pH, 5.0 and 5.5. The highest cell growth was achieved at 20% (w/v) and pH 5.5 of molasses. The fed-batch system was then performed using the best batch fermentation conditions, with a molasses concentration of 13% (w/v) which resulted in high ethanol concentration and fermentation efficiency of 15.96% and 89%, respectively.

• 한국가정과학회지
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• 제5권1호
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• pp.48-61
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• 2002

This study was carried out to investigate the effects of four kinds of leavening agents on Jeung-Pyun fermantation. Milk-wine(M), fresh yeast(F), dry yeast(D), instant yeast(I) were used in Jeung-Pyun ingredients. The physicochemical properties, sensory evaluation were examined. The results of this study are summarized as follows: 1. Basic recipes for Jeung-Pyun by preliminary test were developed. 2. Specific volumes and expansion ratio of Jeung-Pyun was higher in the fresh yeast-added sample. 3. The pH of Jeung-Pyun was decreased significantly as the fermentation progressed 4. In the result comparing Jeung-Pyun extracting after 1st fermentation with Jeung-Pyun extracting 2nd fermentation by SEM, the former was widely distributed in stability of bubble and pore than the latter. 5. Standard recipe by Q.D.A. test added four kinds of leavening agents were as follows: (1)Jeung-Pyun added milk wine was 240min for 1st fermentation time, 60min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 80% for fermentation humidity respectively. (2) Jeung-Pyun added fresh yeast was 90min for 1st fermentation time, 40min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 80% for fermentation humidity respectively. (3)Jeung-Pyun added dry yeast was 90min for 1st fermentation time, 60min for 2nd fermentation time, 35$^{\circ}C$ for fermentation temperature, 60% for fermentation humidity respectively. (4)Jeung-Pyun added instant yeast was 90min for 1st fermentation time, 40min for 2nd fermentation time, 30$^{\circ}C$ for fermentation temperature, 60% for fermentation humidity respectively. 6.Based on sensory evaluation, Jeung-Pyun added fresh yeast was significantry higher than others in color, sweetness, moistness, softness, and overall quality. There was negative significance between milk wine flavor and astrigentness, and yeast flavor.

• 한국식품영양과학회지
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• 제42권5호
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• pp.784-791
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• 2013

시판 효모 4가지(Fermivin, FM; Saf-instant yeast red, SI; Angest wine active dry yeast, AW; Angest instant yeast high sugar, AI)를 이용하여 복분자 발효주를 제조하고, 품질 특성을 비교하였다. 환원당 함량은 FM(2.7%)과 AI(2.8%)가 SI(2.4%)와 AW(2.5%)보다 높았으며, 검출된 주요 유리당인 glucose의 함량은 AW와 AI에서 유의적으로 높았다. 알코올 함량은 AW(11.95%)에서 가장 높고, SI(11.75%)에서 가장 낮았다. pH는 FM(pH 3.73)에서 가장 낮았으며, 총 산도는 효모별로 차이가 없었다. 모든 시료에서 검출된 주요 유기산은 citric acid였으며, 효모별로 검출된 유기산 함량은 달랐다. Malic acid의 경우 SI(2.92 mg/mL)에서 가장 많았고 AI(1.83 mg/mL)에서 가장 적었다. L, a, b 값은 SI에서 높고 AI에서 낮았으며, 탁도는 효모에 따라 차이가 없었다. 복분자 발효주의 total phenolics와 total anthocyanin 함량은 효모 별로 차이가 없었으나, 국내에서 판매되는 수입산 레드 와인보다 높았다. 항산화능 역시 효모별로 차이가 없었으나 FM, AI, AW, SI 순으로 높았으며, 항산화능 지표에는 total phenolics와 anthocyanin의 함량뿐만 아니라 anthocyanin 조성도 영향을 미쳤다.