芦台春酱香型白酒酿造过程中真菌菌群多样性及代谢分析

Analysis of fungal community diversity and metabolism during the brewing process of Lutaichun sauce-flavor Baijiu

该研究采用高通量测序技术对天津芦台春酱香型白酒发酵过程中不同轮次出窖酒醅的真菌群落结构进行研究,并对其与理化因子、挥发性风味成分相关性分别进行典范对应分析(CCA)及偏最小二乘判别分析(PLS-DA)。结果表明,随着轮次的增加,真菌菌群的多样性升高,而丰度先升高后降低;酵母菌是白酒发酵过程中的主要真菌,但相对丰度逐步降低,在属水平上以伊萨酵母属(Issatchenkia)为主,其相对丰度由第一轮次的97.48%逐渐下降至第七轮次的3.53%。相关性分析结果表明,总酸、还原糖和酒精度是窖池发酵微生物演替的重要理化因子;伊萨酵母属(Issatchenkia)与乙酸乙酯、乙酸异戊酯、异戊醇等相关性较大;哈萨克斯坦酵母属(Kazachstania)、丝衣霉属(Byssochlamys)、罗萨氏菌属(Rasamsonia)、复膜孢酵母属(Saccharomycopsis)等与正己酸乙酯、庚酸乙酯、3-羟基丁酸乙酯、丁二酸二乙酯、苯乙酸乙酯、油酸乙酯、乙醇等相关性较大;而Leiothecium、未分类的酵母目(unclassified_o__Saccharomycetales)、Apiotrichum、Cutaneotrichosporon等则对壬酸乙酯、乙酸苯乙酯、正己醇、2,3-丁二醇、糠醇、糠醛等的形成起到重要作用。

In this study,the fungal community structure of fermented grains in different rounds of Lutaichun sauce-flavor Baijiu produced in Tianjin was investigated using high-throughput sequencing technology,and its correlation with physicochemical factors and volatile flavor components were analyzed by canonical correspondence analysis(CCA)and partial least squares-discriminant analysis(PLS-DA),respcetively.The results showed that the diversity of fungal flora during the fermentation of Baijiu increased with the increase of the fermentation rounds,while the abundance showed a tendency of increasing and then decreasing.Yeast was the main fungus in the fermentation process of Baijiu,with the increase of the fermentation rounds,the relative abundance of yeast decreased,and at the genus level was dominated by the genus Issatchenkia.Its relative abundance gradually decreased from 97.48%in the first round to 3.53%in the seventh round.Correlation analysis results showed that total acid,reducing sugar and alcohol content were important physicochemical factors in the microbial succession of pit fermentation.Issatchenkia was more correlated with ethyl acetate,isoamyl acetate and isoamyl alcohol;Kazachstania,Byssochlamys,Rasamsonia,and Saccharomycopsis were more correlated with ethyl n-caproate,ethyl enanthate,ethyl 3-hydroxybutyrate,diethyl succinate,ethyl phenylacetate,ethyl oleate,and ethanol;while Leiothecium,unclassified_o__Saccharomycetales,Apiotrichum,and Cutaneotrichosporon played an important role in the formation of ethyl nonanoate,phenylethyl acetate,n-hexanol,2,3-butanediol,furfuryl alcohol,and furfural.