A multiple-step strategy for screening Saccharomyces cerevisiae strains with improved acid tolerance and aroma profiles.

Acid tolerance and aroma profile are crucial factors for wine production in Saccharomyces cerevisiae. However, most wine yeasts to date fail to endure low-pH environments, therefore resulting in problems such as lengthened fermentation and poor flavor during acidic fruit wine production. In the present study, we established a multiple-step screening strategy, which was composed of atmospheric and room temperature plasma (ARTP), high-throughput screening (HTS), and laboratory adaptive evolution (ALE), to screen yeast strains for potential wine-producing with enhanced performances during low pH conditions. Importantly, we obtained the S. cerevisiae strain from the mutant library, ET008-c54, which displayed exhibited excellent performances in survival rate, fermentation time, aroma profile, and genetic stability. More specifically, the survival rate of ET008-c54 at low pH was increased by 10-fold, the fermentation time of greengage plum wine was shortened by about 70%, and the content of main aroma compounds was significantly increased by 52%. Collectively, we demonstrate the practical application of the screening platform designed for discovering mutant strains in winemaking technology. Key Points • A novel multi-step method was developed for screening wine-producing yeast. • Acid tolerance and aroma profiles of yeast were improved by the proposed method. • ET008-c54 showed excellent fermenting performance and stability at low pH. [ABSTRACT FROM AUTHOR]