Abstract:The fruity-flavored yeast SSF12 was used as the research object and another strain NGF6 with poor fruity flavor was used as the control to study their transcriptomic differences in the process of wine fermentation. Combined with the physical and chemical indexes, aroma substances content and sensory characteristics of fermentation broth, the metabolic characteristics and related regulated mechanism of aroma substances of fruity yeast were revealed. Results showed that SSF12 had higher sugar utilization and fermentation degree. The contents of esters, alcohols and terpenes in the fermentation broth of SSF12 were higher than that of NGF6, while the contents of aldehydes and fatty acids were lower than NGF6. Meanwhile, the fruity sensory characteristics of the fermentation broth of SSF12 were significantly better than that of NGF6. Transcriptomic analysis showed that there were 434 genes differentially expressed in SSF12 compared with NGF6 (including 290 up-regulated genes and 144 down-regulated genes). KEGG analysis showed that SSF12 had more up-regulated genes in carbohydrate (especially sugars, higher alcohols and esters) metabolism and nucleic acid metabolism, thus might be more prominent in these pathways. NGF6 had more up-regulated genes in pathways of acetaldehyde synthesis, fatty acid synthesis and some amino acid metabolism. The differentially expressed genes such as ADH2, ADH6, ALD3, and ATF2 were closely related to aroma substances metabolism. So they can be used as candidate genes for wine aroma improvement. Results of this study might provide a reference for the breeding and strain improvement of fruity-flavored yeasts.