浓香型白酒人工窖泥微生物群落演替与酿造酒质变化的关系研究

Chinese strong-flavor Baijiu (CSFB) dominated the Chinese Baijiu-making industry, playing a crucial role in national economic development. CSFB is produced by fermentation of grains in cellars lined with pit mud. This pit mud contains large amounts of the functional microbes which are important to the production of aromatic compounds in CSFB. Thus, the composition of pit mud microbial communities determines the quality of CSFB. The long maturation period and the degradation of pit mud caused by microbial factors seriously restrict the productivity of high quality CSFB during production. Artificial pit mud is a fermented product that uses yellow soil or degraded pit mud as the primary material incubated with brew microbes. In the Chinese Baijiu industry, an efficient approach to increase the productivity of high quality CSFB is to construct new cellars and repair the degraded cellars with artificial pit mud. However, despite its obvious enhancement effect on the quality of CSFB, the microbial community structure and its impact on CSFB quality remain to be understood. This lack of information hinders the standardization production of artificial pit mud. This study characterizes the relationship between the succession of microbial community structure in artificial pit mud and CSFB quality variation during the production process using metagenomic and metabonomic technology as the main approaches, combined with a 16S rRNA High-throughput sequencing and physicochemical analysis. Our aim is to reveal the identity of functional microbes associated with high quality CSFB production in artificial pit mud. The data presented within this study will provide guidelines for the future standardization production of artificial pit mud.

浓香型白酒 (Chinese strong-flavor Baijiu; CSFB) 主导我国酿酒工业发展，在国民经济建设中具有重要地位。窖池是 CSFB 酿造原料发酵的特征容器。窖池中的窖泥是酒体生香功能微生物的繁殖载体，其菌群结构决定 CSFB 质量。在生产中，由微生物因素引起的窖泥成熟慢和窖泥退化严重制约优质 CSFB 产能。人工窖泥是指向黄泥或退化窖泥人为接种酿酒功能菌发酵形成的产物。利用人工窖泥新建窖池和改良退化窖池扩大优质 CSFB 产能是酿酒工业最重要的生产实践。虽然取得了显著的应用效果，但人工窖泥微生物菌群结构及其对 CSFB 质量的影响仍不清楚，阻碍其标准化生产。本项目以宏基因组和代谢组学技术为主要手段，结合 16S rRNA 高通量测序和常规理化分析，研究人工窖泥微生物群落演替与酿造酒质变化的关系，揭示人工窖泥提升酒质的功能微生物类群，为实现人工窖泥标准化生产提供依据。

利用人工窖泥新建窖池和改良退化窖池扩大优质浓香型白酒 (CSFB) 的产能是酿酒工业最重要的生产实践。虽然取得了显著的应用效果，但人工窖泥微生物菌群结构及其对 CSFB 质量的影响仍不清楚，阻碍其标准化生产。本项目结合宏基因组、宏蛋白质组和代谢组学技术研究人工窖泥微生物群落演替与酿造酒质变化的关系，揭示人工窖泥提升酒质的功能微生物类群，为实现人工窖泥标准化生产提供依据。项目主要结论：(1) 在酿造过程中，人工窖泥微生物群落结构发生了剧烈演替。Clostridia 和 Bacilli 是主导群落演替的关键菌群。伴随酿造酒质的提高，Clostridia / Bacilli的丰度比值上升。(2) 人工窖泥理化因子、微生物群落结构、酒体香味物质之间具有显著的相关性。有效磷、有效钾是影响人工窖泥细菌群落结构分布的主要理化因子，推测适当提高它们的含量有助于促进酿酒有益微生物生长，提升酿造酒质和饮后舒适度。(3) 在酿造过程中，人工窖泥微生物的功能发生了显著改变。与酒体关键香味物质（己酸乙酯、丁酸乙酯、乳酸乙酯、乙酸乙酯）合成联系最密切的代谢通路是丁酸代谢和丙酮酸代谢。随着酒质的增强，丁酸代谢通路的功能显著提高。本项目结果为充分认识中国白酒发酵机理奠定了基础，可为人工窖泥培养技术的优化完善提供依据。