Effect of indigenous Saccharomyces cerevisiae strains on microbial community successions and volatile compounds changes during Longyan wine fermentation

In Longyan grape, as a unique white wine variety in China, the connection between starters and wine flavor is poorly understood. Thus, this study compared the effects of commercial yeast VL2 and three selected native Saccharomyces cerevisiae strains on the microbial community and volatile compounds during alcohol fermentation of Longyan wine. Results showed that the indigenous yeast strain FMS can initiate fermentation faster than other strains. A total of 60 aromatic compounds were identified in all fermentation samples, and the concentration of volatile compounds in wines inoculated with FMS (9619.61 ± 500.18 μg/L) was significantly higher than in VL2 wines (8358.91 ± 131.48 μg/L). Moreover, the microbial diversity differed among the four strains, with the FMS fermentation samples having the highest microbial genus of 470. The core microorganisms of VL2 (13), JCT (15), FMS (18), and FML (12) wines were identified using OPLS analysis and Spearman's correlation analysis, respectively. Among them, Lactobacillus, Paenibacillus, and Pichia were the unique microorganisms in FMS wines, which performed a crucial part in the synthesis of aromatic compounds such as hexyl acetate, ethyl butanoate, ethyl octanoate, and ethyl 9-decenoate. Therefore, FMS wines has effectively improved the quality of the wines and diversified the organoleptic quality of Longyan wines from Huaizhuo Basin. This study provided useful references for understanding the role of brewing yeast in the formation of flavor compounds during the fermentation process of Longyan dry white wine, as well as the application of indigenous brewing yeast in the wine industry.