芽孢杆菌强化发酵降低小曲白酒中高级醇的含量

为探索芽孢杆菌的添加对小曲酒高级醇含量的影响，以13株大曲来源的芽孢杆菌为出发菌株，通过固态发酵和液态发酵，得到2株可降低小曲酒高级醇含量的芽孢杆菌；经过形态、生理生化和16S rDNA测序分析，鉴定菌株B8为地衣芽孢杆菌（Bacillus licheniformis），菌株B13为贝莱斯芽孢杆菌（Bacillus velezensis）；将2株功能芽孢杆菌制成芽孢杆菌麸曲，进行小试和中试小曲白酒固态酿造试验，验证芽孢杆菌对小曲白酒风味物质的影响。结果表明，B8与B13强化发酵可明显降低高级醇含量，主要变现为异戊醇与异丁醇的降低，以及微量正戊醇的产生，中试最高降低率可达29.87%，且低于某市售小曲清香型白酒成品酒中高级醇含量。该研究为解决小曲白酒中高级醇含量偏高问题提供了方法，以期提高小曲白酒质量。

Concentration of Higher Alcohols in Xiaoqu Liquor Induced by Enhanced Fermentation with Strains of Bacillus

To explore the effect of Bacillus addition on higher alcohol content in Xiaoqu liquor, 13 Bacillus strains from Daqu were used as the starting strains. Through solid-state and liquid fermentation, two functional strains with the ability to reduce the higher alcohol content of Xiaoqu liquor were obtained. The strain B8 was identified as Bacillus licheniformis and strain B13 as Bacillus elezensis by morphological, physiological and biochemical analyses and 16S rDNA sequencing. The two functional Bacillus strains were used to make Bacillus fuqu, and small and medium scale solid-state fermentation experiments of xiaoqu liquor were carried out to verify the effect of Bacillus on the flavor substances of Xiaoqu liquor. The results showed that the enhanced fermentation with B8 and B13 could significantly reduce the contents of higher alcohols, which were mainly due to the reduction of isoamyl alcohol and isobutanol, and the production of trace n-amyl alcohol. The highest reduction rate for the pilot experiments reached 29.87%, which was lower than the contents of higher alcohols in the commercial finished liquor of Xiaoqu clear flavor liquor. The study provides a method for solving the problem of high content of higher alcohols in Xiaoqu liquor, which is expected to help improve the quality of Xiaoqu liquor.