• 한국환경보건학회지
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• 제7권1호
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• pp.51-57
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• 1981

This Study was carried out to investigate yeast and mold contamination in fermented milk products produced by 9 different domestic manufacturers from October 20. to December 5. 1980 The results obtained in the study were as follows 1) pH values of the products were ranged from pH 3.14 to pH 4.20 and average of sour milk drinks was pH $3.66\pm 0.19$ and fermented milks pH $3.74\pm 0.11$. Therefore the difference of pH average among sour milk drinks and fermented milks was statistically significant. (p<0.01) 2) In case of yeast contamination, yeast was found on all the four producted at the same date. From this result, it seemed that yeast contamination occured during the manufacturing progress. 3) Degree of contamination by the indicator organisms was E. coli positive, 3.7%: over 1,000 yeasts/ml, 14.8% over 10 molds/ml, 0.9%. 4) In the range of over 1,000 yeasts/ml, degree of contamination by yeast was 8.4% in fermented milk and 16.7% in sour milk drink. 5) Yeasts in product C increased to the spoilage number within 5 days and in H increased within 10 days at 5C. At 15$\circ$C, yeast increased to the spoilage number within 15 days in product A.D. 6) It seems that the yeast number of initial contamination should be important than the increase rate as criteria on the fermented Milk products.

• Journal of Microbiology and Biotechnology
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• 제33권10호
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• pp.1329-1336
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• 2023

Microbial fermentation is often used to improve the functionality of plant-based food materials. Herein, we investigated changes in the physicochemical and functional properties of cabbage during yeast fermentation to develop new products using fermented cabbage. Among the 8 types of food-grade yeast, both Saccharomyces cerevisiae and Saccharomyces boulardii fermented 10% cabbage powder solution (w/w) the most effectively, leaving no soluble sugars after 12 h of fermentation. In addition, the yeast fermentation of cabbage resulted in functionally positive outcomes in terms of sulforaphane content, antioxidant properties, and anti-inflammatory activity. Specifically, the yeast-fermented cabbages contained about 500% more sulforaphane. The soluble fraction (5 ㎍/ml) of yeast-fermented cabbage had no cytotoxicity in murine RAW 264.7 cells, and the radical-scavenging capacity was equivalent to 1 ㎍/ml of ascorbic acid. Moreover, cabbage fermented with S. boulardii significantly suppressed both lipopolysaccharides (LPS)-induced nitric oxide production and LPS-induced reactive oxygen species production in RAW 264.7 cells, suggesting a potential anti-inflammatory effect. These results support the idea that yeast fermentation is promising for developing functionally improved cabbage products.

• Asian-Australasian Journal of Animal Sciences
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• 제28권6호
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• pp.816-826
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• 2015

The present experiment evaluated the influence of moisture level and anaerobic fermentation on aerobic stability of total mixed ration (TMR). The dynamic changes in chemical composition and microbial population that occur after air exposure were examined, and the species of yeast associated with the deterioration process were also identified in both non-fermented and fermented TMR to deepen the understanding of aerobic deterioration. The moisture levels of TMR in this experiment were adjusted to 400 g/kg (low moisture level, LML), 450 g/kg (medium moisture level, MML), and 500 g/kg (high moisture level, HML), and both non-fermented and 56-d-fermented TMR were subjected to air exposure to determine aerobic stability. Aerobic deterioration resulted in high losses of nutritional components and largely reduced dry matter digestibility. Non-fermented TMR deteriorated during 48 h of air exposure and the HML treatment was more aerobically unstable. On dry matter (DM) basis, yeast populations significantly increased from $10^7$ to $10^{10}cfu/g$ during air exposure, and Candida ethanolica was the predominant species during deterioration in non-fermented TMR. Fermented TMR exhibited considerable resistance to aerobic deterioration. Spoilage was only observed in the HML treatment and its yeast population increased dramatically to $10^9cfu/g$ DM when air exposure progressed to 30 d. Zygosaccharomyces bailii was the sole yeast species isolated when spoilage occurred. These results confirmed that non-fermented and fermented TMR with a HML are more prone to spoilage, and fermented TMR has considerable resistance to aerobic deterioration. Yeasts can trigger aerobic deterioration in both non-fermented and fermented TMR. C. ethanolica may be involved in the spoilage of non-fermented TMR and the vigorous growth of Z. bailii can initiate aerobic deterioration in fermented TMR.

• 산업식품공학
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• 제15권4호
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• pp.413-419
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• 2011

쌀단백질을 이용한 고부가가치 천연 조미소재를 개발하기 위하여 쌀단백질을 프로테아제로 효소분해한 배지에서 Saccharomyces cerevisiae를 배양하여 제조한 효모 추출물(Yx)에, 효소분해 후 남은 쌀단백질 잔사를 Bacillus licheniformis 혹은 Bacillus subtilis로 발효하여 얻은 발효물(Rfl, Rfs)을 각각 첨가하였다. 쌀단백질 잔사의 발효물이 첨가된 효모추출물(YxRfl, YxRfs)의 전체적 선호도는 첨가전의 효모추출물(Yx)에 비하여 높았으며, 특히 쌀단백질 발효물의 보충에 의해서 감칠맛과 같은 풍미가 증가함을 미각센서 분석 및 관능검사에 의해서 확인할 수 있었다. 쌀단백질 잔사발효물에 의한 감칠맛의 상승은 감칠맛을 내는 아미노산 이 외에도 쌀단백질의 발효에 따라 유리된 다양한 펩타이드 분획의 영향이 있었을 것으로 예상된다. 이와 같이 감칠맛 아미노산 및 펩타이드가 함유된 쌀단백질 발효물이 보충된 효모추출물은 감칠맛과 풍미의 상승작용으로 전체적인 기호도가 높아짐에 따라 고부가가치 천연조미소재의 제조에 응용될 수 있을 것으로 기대되었다.

• 한국식품조리과학회지
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• 제26권4호
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• pp.422-427
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• 2010

This study was conducted to investigate the antioxidant effect and properties of unfermented tea and fermented tea made with Rhodotorula yeast. The levels of crude fat and crude protein in the fermented tea were higher than those in the unfermented tea. The water-soluble phenol levels of unfermented tea and fermented tea were 912.5 and 2,445.24 ppm, respectively. The total amino acid content of fermented tea was greater than that of unfermented tea;,- the amino acid concentrations of alanine, valine, leucine, and lysine were 25.58, 24.38, 27.96, and 14.14 ${\mu}g/mL$, respectively. The DPPH radical scavenging activities of the unfermented and fermented teas were 32.14 and 41.57%, respectively; this is in contrast to 29.73% for L-ascorbic acid(150 ppm). The reducing power activity of fermented tea was 41.57%, and that of unfermented tea was 32.14%.

• 동아시아식생활학회지
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• 제21권1호
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• pp.82-87
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• 2011

김치 원료로부터 덱스트란 생성균과 탁주 효모균이 식혜에 첨가된 설탕을 이용하여 올리고당과 알코올을 생산하는 것을 바탕으로 기능성 알코올 발효 음료 제조를 연구하였다. 식혜 제조를 위한 최대 당화 시간은 가용성 고형물의 변화가 증가한 후 완만하게 되어지는 5시간 내외가 차후 알코올성 발효음료 제조를 위해 적당하였다. 알코올 발효 시 탁주 효모만 사용하였을 경우 약 3%(w/v)가 생성되었으며, 덱스트란 생성균만 접종하였을 경우 알코올 발효는 이루어지지 않았다. 덱스트란생성균과 탁주 효모를 혼합 접종하였을 경우 약 4%(w/v)의 에탄올이 생성되었다. TLC 분석 결과, 탁주 효모만 접종했을 경우 올리고당은 생성되지 않았으며, 탁주 효모와 덱스트란 생성균의 혼합 접종시 설탕을 48시간 안에 사용하였으며, 발효 과정 중 올리고당으로 추정되는 점적을 확인할 수 있었다. 위와 같이 덱스트란 생성균과 탁주 효모를 이용한다면 기능성 올리고당과 알코올을 생성하여 새로운 형태의 기능성 알코올 발효 음료의 생산이 가능할 것으로 보여진다.

• 한국식품저장유통학회지
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• 제17권2호
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• pp.174-181
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• 2010

참다래로 만든 'Hayward' 와인 제조에 적합한 효모 선발을 위해서 3종의 효모에 의한 발효과정에서의 물리화학적 특성 변화를 조사 분석하였다. 사용된 효모는 Saccharomyces cerevisiae Gervin No.5 strain (GVN), S. bayanus Lavin strain EC1118 (EC1118), 그리고 S. cerevisiae Red star Davis No.796 (No.796)은 와인 발효에 가장 적합하여 상업적으로 이용되고 있는 효모이다. 이 세 효모에 의해 발효된 샘플의 당도 함량은 비슷하게 감소하였으나, 알코올 생산량만 발효 첫 주에 큰 차이가 있었다. 효모중 GVN이 13.8%로 알콜농도가 가장 높았고, 반면에 No.796과 EC1118은 각각13.0%와 12.5%로 상대적으로 알콜함량이 낮았다. 관능평가에서 GVN은 높은 산과 높은 알콜함량을 가지고 있고, 강한 풍미와 쓴맛을 가진 것으로 평가되었다. No.796은 GVN과 유사하지만 낮은 알콜함량과 함께 단맛이 있었다. EC1118은 높은 풍미, 단맛과 낮은 알콜함량으로 부드러운 맛으로 평가되었다. EC1118에 의해 발효된 와인 의 총페놀과 항산화 활성은 다른 효모보다 높았다. 따라서 본 연구에서EC1118이 최적의 효모로 선발되었다. 다른 2종의 효모를 사용한 참다래 발효 와인은 각각 다른 품질 특성을 나타내었다. EC1118효모는 참다래 발효에 가장 바람직한 특성을 가지고 있었다. 이러한 특성은 주로 총페놀과 항산화 활성과 같은 건강기능성과 높은 관능적 기호도를 가지고 있었다.

• 한국식품조리과학회지
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• 제30권3호
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• pp.307-316
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• 2014

This study was carried out in order to investigate the quality characteristics of baguette with different amounts of yeast and fermented rice bran sourdough(Control: Yeast 30 g + Fermented rice bran sourdough 0 g, A sample: Yeast 20 g + Fermented rice bran sourdough 150 g, B sample: Yeast 10 g + Fermented rice bran sourdough 300 g, C sample: Yeast 0 g + Fermented rice bran sourdough 450 g). The pH of fermented rice bran sourdough by fermentation time was decreased as the fermentation time was longer. The pH of baguette dough was decreased as the fermented rice bran sourdough increased; the volume was the highest in control at the 1st fermentation, and in the B sample at the 2nd fermentation. The weight of baguette was the highest in the C sample, and the volume and specific volume were the highest in the B sample. The microstructure of the cross section analysis indicated that the air cell of baguette crumb was large and regular in the B sample. The moisture content and water binding capacity were the highest in the B sample, although significantly different. The L value was decreased as there was an increasing addition ratio of fermented rice bran sourdough; further, the a and b values were decreased with an increase in baguette volume. Hardness, gumminess and chewiness were decreased as volume and specific volume were increased; yet, springiness was increased. According to the result of the sensory evaluation, the flavor, taste, appearance and texture were the highest in the B sample.

• 동아시아식생활학회지
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• 제20권4호
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• pp.531-535
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• 2010

This study investigated the effects of different commercial yeast strains on the characteristics of peach wine. Peach fruit was inoculated with Fermivin, K1-V1116, EC-1118, D-47 and AR2. Peach wines fermented with the D-47, K1-V1116, and AR2 strains showed faster fermentation than wines fermented with the other strains. Wine fermented with EC-1118 had the lowest titratable acidity and highest pH. The ethanol content of wines fermented with different commercial yeast strains was in the range of 13~14%. In sensory evaluation, the wine made with EC-1118 showed the highest overall scores in color and acceptability.

• 한국축산식품학회지
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• 제40권4호
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• pp.541-550
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• 2020

The use of yeast assist kefir fermentation, but also can cause food spoilage if uncontrolled. Hence, in this study, the microbial composition of an existing commercial kefir starter was modified to produce a functional starter, where Lactobacillus acidophilus KCNU and Lactobacillus brevis Bmb6 were used to replace yeast in the original starter to produce non-yeast kefir-like fermented milk. The functional starter containing L. acidophilus KCNU and L. brevis Bmb6 demonstrated excellent stability with 10¹⁰ CFU/g of total viable cells throughout the 12 weeks low-temperature storage. The newly developed functional starter also displayed a similar fermentation efficacy as the yeast-containing control starter, by completing the milk fermentation within 12 h, with a comparable total number of viable cells (10⁸ CFU/mL) in the final products, as in control. Sensory evaluation revealed that the functional starter-fermented milk highly resembled the flavor of the control kefir, with enhanced sourness. Furthermore, oral administration of functional starter-fermented milk significantly improved the disease activity index score by preventing drastic weight-loss and further deterioration of disease symptoms in DSS-induced mice. Altogether, L. acidophilus KCNU and L. brevis Bmb6 have successfully replaced yeast in a commercial starter pack to produce a kefir-like fermented milk beverage with additional health benefits. The outcome of this study provides an insight that the specific role of yeast in the fermentation process could be replaced with suitable probiotic candidates.