浓酱兼香型白酒发酵酒醅微生物群落及理化指标对正丙醇产出的影响

该研究从24份浓酱兼香型白酒二轮次出池酒醅筛选出正丙醇含量高、中、低酒醅样品，对其理化指标进行分析，采用高通量测序技术分析其微生物群落结构，基于冗余分析（RDA）探讨正丙醇产量与理化因子、微生物群落相关性。结果表明，3份酒醅样品水分、总酸、还原糖以及氨基酸态氮含量差异显著（P＜0.05）；共检出16个微生物属（3个细菌属，13个真菌属），其中，共有优势细菌属为乳杆菌属（Lactobacillus）（相对丰度＞1%），共有优势真菌属为曲霉属（Aspergillus）、伊萨酵母属（Issatchenkia）（相对丰度＞1%）。RDA结果表明，酒醅的水分、氨基酸态氮、总酸、乳杆菌属、曲霉属、伊萨酵母属、嗜热子囊菌属（Thermoascus）、毕赤酵母属（Pichia）与正丙醇产出呈负相关，还原糖、毛孢子菌属（Trichosporon）、枝芽孢杆菌属（Virgibacillus）、克罗彭斯特菌属（Kroppenstedtia）与正丙醇产出呈正相关。

Effects of microbial community and physicochemical indexes of fermented grains of strong-sauce-flavor Baijiu on n-propanol production

Fermented grains samples with high, medium and low n-propanol content were selected from 24 second round of the unloading pit of strong- sauce-flavor (Jianxiangxing) Baijiu, their physicochemical indexes were analyzed, the microbial community structure was analyzed by high-throughput sequencing technique, and the correlation between n-propanol yield and physicochemical factors, and microbial community was explored based on redundancy analysis (RDA). The results showed that the contents of water, total acid, reducing sugar and amino acid nitrogen in 3 fermented grains samples were significantly different (P＜0.05). A total of 16 microbial genera (3 bacterial genera and 13 fungal genera) were detected, among them, the common dominant bacterial genus was Lactobacillus (relative abundance＞1%), the common dominant fungal genera were Aspergillus and Issatchenkia (relative abundance＞1%). RDA results showed that the water, amino acid nitrogen, total acid, Lactobacillus, Aspergillus, Issatchenkia, Thermoascus and Pichia were negatively correlated with n-propanol production, reducing sugar, Trichosporon, Virgibacillus and Kroppenstedtia were positively correlated with n-propanol production.