基于磷脂脂肪酸技术研究酱香大曲微生物群落结构

Study of microbial community structure of sauce-flavor Daqu based on PLFA technology

为了解制曲环境、峰值温度对大曲微生物群落结构特征的影响,以4种不同的酱香型大曲为对象,研究酿造特征参数、微生物群落特征及挥发性组分之间的相关性.结果表明:4种大曲样品中共计检出16种磷脂脂肪酸(Phospholipid fatty acid,PLFA),总PLFA含量表现为泸州老窖大曲(LZ)>国台大曲(GT)>郎酒大曲(LJ)>仙潭大曲(XT).酱香大曲主要由真菌、G+菌、G-菌等组成,优势菌群均为真菌,且制曲峰值温度相近的样品在聚类分析图上聚类成簇.综合来看,大曲酿造特征参数与大曲微生物数量和生物量呈正相关,大曲挥发性组分组成特征主要取决于G+菌生物量.

This study aimed to understand the effect of the processing environment and the highest temperature on the structure of microbial communities in Daqu liquors. The different characteristics of four different kinds of sauce-flavor Daqu liquors were investigated, including brewing characteristic parameters, microbial community structure and the composition of the volatile components. The four Daqu samples used in this study were obtained from four different liquor factories. The name of Daqu are as follows： Luzhou Daqu（LZ）, Guotai Daqu（GT）, Langjiu Daqu（LJ） and Xiantan Daqu（XT）. A total of 16 PLFAs were detected from 4 Daqu samples, with the order of the total amount of PLFAs as LZ 〉GT〉 LJ〉 XT. The microflora of sauce-flavor Daqu was composed of fungi, Gram＋ bacteria, and Gram- bacteria, with fungi as the predominant microorganisms. Moreover, samples with similar maximum temperature clustered as a group in cluster analysis. In summary, the characteristic parameters of brewing displayed a positive correction with the biomass; the composition of volatile compounds depended on the biomass of Gram＋ bacteria.