清香型白酒固态酿造过程中酵母种群结构和多样性分析

Identification and analysis of yeast community structure in Chinese light-style liquor brewing process

摘要:

【目的】探索清香型白酒固态酿造过程中酵母的种群结构和生态多样性变化规律, 为科学认识白酒酿造的过程与机制提供理论依据。【方法】运用WL鉴别培养基和26S rRNA D1/D2序列分析方法对清香型白酒3种典型大曲和酒醅发酵过程的酵母进行分类学研究。【结果】从清香型白酒固态酿造过程中共鉴定出10种酵母, 分别为Saccharomyces cerevisiae、Issatchenkia orientalis、Pichia anomala、Saccharomycopsis fibuligera、Pichia fermentans、Trichosporon asahii、Hanseniaspora osmophila、Pichia farinosa、Pichia membranifaciens和Clavispora lusitaniae。其中T. asahii、C. lusitaniae、H. osmophila、P.?membranifaciens、P. farinose和P. fermentans为首次从清香型白酒酿造过程中分离获得的酵母种类。考察3种典型大曲(清茬、红心、后火曲)和大茬、二茬酒醅发酵过程的酵母种群结构变化规律显示, 3种大曲具有相同的优势菌种S. fibuligera, 但三者酵母结构组成差异较大, 且清茬曲含有最多的酵母数量和种类。酒醅发酵过程中的酵母种群结构与3种大曲均明显不同, 大茬和二茬酒醅酵母结构也不同, 两种酒醅发酵后期的优势酵母均为S. cerevisiae, 而发酵前期优势酵母则分别是H. osmophila和P. membranifaciens。【结论】深入研究了清香型白酒酿造过程中微生物的分布特征和规律, 对认识清香型白酒酿造过程和群体微生物的发酵机制, 以及丰富我国传统酿造食品微生物的研究, 具有重要的理论和实践价值。

Abstract:

[Objective] This work aimed to explore yeast community structure and ecological diversity in making process of Chinese light-style liquor, which would be benificial for scientifically understanding of the formation mechanism of Chinese light-style liquor. [Methods] Yeast variety and quantity during making process of Chinese light-style liquor was investigated by WL medium and 26S rRNA D1/D2 region sequence analysis. [Results] Ten yeast species were identified as Saccharomyces cerevisiae, Issatchenkia orientalis, Pichia anomala, Saccharomycopsis fibuligera, Pichia fermentans, Trichosporon asahii, Hanseniaspora osmophila, Pichia farinosa, Pichia membranifaciens and Clavispora lusitaniae. Among them, T. asahii, P. membranifaciens, H. osmophila, P. farinose and P. fermentans were firstly isolated in Chinese light-style liquor. Athough the quantity of S. fibuligera dominated in three types of Daqu, yeasts ecological distribution was different. There were the most amount and varieties of yeast species in Daqu of Qincha. Yeast community structure of fermented grain was also different from that of Daqu and difference also existed between fermented grain of Dacha and Ercha. S. cerevisiae was dominant at later stage of liquor fermentation, while the dominant species in Dacha and Ercha were H. osmophila and P. membranifaciens at early stage, respectively. [Conclusion] This work deeply studied the yeast distribution characteristics and community structure in making process of Chinese light-style liquor, which would show great value in scientifically understanding of the formation mechanism of Chinese light-style liquor.