Environmental resistance of indigenous Saccharomyces cerevisiae with tolerance to potassium metabisulfite at the microbial succession stage of fermenting Campbell Early grape

Several indigenous sulfite-resistant yeasts were isolated at the microbial succession stage of yeast flora during spontaneous fermentation of Campbell Early grapes using a YPD plate that contained 200 mg/L or 500 mg/L potassium metabisulfite. When they were applied to the wine fermentation using the Campbell Early grape and apple juices, strains S13 and D8 showed strong alcohol fermentation and good flavor production. They were identified as Saccharomyces cerevisiae in the phylogenetic analysis based on their ITS 1-5.8S-ITS II DNA sequences. The two yeast strains grew to a high cell density in the YPD media supplemented with 40%(w/v) glucose. They also grew rapidly in the YPD media at $40^{\circ}C$. While strain S13 showed some differences in cell density at the two temperatures, no marked difference was observed during the culture of strain D8. The strains grew relatively well at pH 5.0 and 9.0 compared with pH 7.0, which was the optimum pH for their growth. Especially, strain S13 cultivated in the YPD media at pH 9.0 grew to 93% of the growth of strain D8, which was obtained at pH 7.0.

캠벨얼리 와인발효 중 효모 천이단계에서 분리된 아황산 내성 토착형 효모의 환경내성

경북 상주와 영주 일원에서 수확한 캠벨얼리 포도의 자연발효 중S. cerevisiae가 처음으로 나타나면서 효모의 천이한 결과, $40^{\circ}C$의 온도에서도 비교적 양호한 생육도를 나타내어 S13 균주는 $30^{\circ}C$에 비하여 약 63%, D8 균주는 약 81%의 생육도를 나타내었다. 두 균주 모두 pH 7.0에서 생육도가 가장 높았으며 pH 5.0과 9.0에서도 비교적 양호한 생육도를 나타내었다. 특히 균주 S13은 pH 9.0에서도 생육이 양호하였으며 pH 7.0에서의 생육도와 비교하여 약 93%의 생육도를 나타내었다.