Microbial diversity during wine fermentation in Beijing region and its influence on wine flavor

To investigate the "microbial terroir" in vineyard of Beijing and its effect on the flavor of wine fermented by coldresistant grapes, the microbial community from vineyard to fermentation both in spontaneous fermentation and fermentation with commercial yeast was investigated by High-throughput Sequencing. The flavor dynamics were analyzed by Gas Chromatography-Ion Mobility Spectrometer. Results showed that Acinetobacter, Pseudomonas and Gluconobacter derived from grapes entered to fermentation and became the dominant bacterial genera. Hanseniaspora from grapes gradually decreased and Saccharomyces became the dominant fungus in the late fermentation stage. A total of 55 typical volatile flavor compounds were detected during fermentation. Two-way Orthogonal Partial Least Squares were applied to reveal the correlation between microorganisms and flavor substances. A total of 8 fungal genera and 17 bacterial genera were strongly correlated with volatile organic compounds during wine fermentation. Saccharomyces was positively correlated with 1-penten-3-ol, ethyl butanoate, ethyl hexanoate M, and butanone, but negatively correlated with isobutyl propionate and acrolein. Hanseniaspora had a strong positive correlation with six flavor compounds: 1-hexanol, ethyl isobutyrate D, ethyl 3-methylbutanoate, ethyl hexanoate, butanal D, and 2,2,4,6,6-pentamethylheptane. This research provided the basis for the development and utilization of indigenous microorganisms in the vineyards of Beijing.