Isolation and Investigation of Potential Non- Yeasts to Improve the Volatile Terpene Compounds in Korean Muscat Bailey A Wine.

The Muscat Bailey A (MBA) grape, one of the most prominent grape cultivars in Korea, contains considerable amounts of monoterpene alcohols that have very low odor thresholds and significantly affect the perception of wine aroma. To develop a potential wine starter for Korean MBA wine, nine types of non- yeasts were isolated from various Korean food materials, including , Sémillon grapes, persimmons, and Muscat Bailey A grapes, and their physiological, biochemical, and enzymatic properties were investigated and compared to the conventional wine fermentation strain, W-3. Through API ZYM analysis, JK04, S7, S8, S18, and S36 were revealed to have β-glucosidase activity. Their activities were quantified by culturing in growth medium composed of different carbon sources: 2% glucose, 1% glucose + 1% cellobiose, and 2% cellobiose. JK04 and S36 showed the highest β-glucosidase activities in all growth media; thus, they were selected and utilized for MBA wine fermentation. MBA wines co-fermented with non- yeasts ( JK04 or S36) and W-3 showed significantly increased levels of linalool, citronellol, and geraniol compared to MBA wine fermented with W-3 (control). In a sensory evaluation, the flavor, taste, and overall preference scores of the co-fermented wines were higher than those for the control wine, suggesting that JK04 and S36 are favorable wine starters for improving Korean MBA wine quality.