Effects of Pichia kluyveri on the flavor characteristics of wine by co-fermentation with Saccharomyces cerevisiae.

Non-Saccharomyces cerevisiae can effectively improve the wine quality by co-fermentation with Saccharomyces cerevisiae. In this study, the effects of Pichia kluyveri DG2 on the flavor characteristics of wine when co-culturing with S. cerevisiae MT were systematically researched. Compared to the fermentation by S. cerevisiae alone, P. kluyveri slowed down the fermentation process slightly but increased the productions of glycerol and esters (8.5% and 142%). Additionally, yield of total higher alcohols reduced in the co-fermentation. The sensory characteristics of the wine obtained by co-fermentation were improved obviously. Transcriptome analysis further showed that 512 genes were differentially expressed in S. cerevisiae in the co-fermentation, of which 318 genes were up-regulated including genes participating in the biosynthesis of flavor compounds in wine and 194 genes were down-regulated including the ones involved in glycolytic and amino acid metabolic pathways. These results indicated that P. kluyveri was a very promising non-S. cerevisiae for co-fermentation to regulate flavor and improve quality of wine. [ABSTRACT FROM AUTHOR]