浓香型白酒酿造大曲及糟醅中功能芽孢杆菌的筛选

为从白酒酿造中分离筛选出有助于提高浓香型白酒风味成分的芽孢杆菌,本文从浓香型白酒酿造的大曲和糟醅中分离得到了55株芽孢杆菌,通过筛选得到了一株在发酵液中产生较多己酸乙酯和较少正丙醇的菌株,编号为YB-16,该菌株所产己酸乙酯含量符合国标高度优级酒的范围,所产正丙醇含量符合国标特级食用酒精的范围。通过对该菌株进行形态特征观察、生理生化特征分析、分子生物学鉴定和构建系统发育树,发现YB-16与Bacillus cereus strain CCM NBRC 15305聚为一个分支,亲缘关系最近,可将菌株YB-16鉴定为蜡质芽孢杆菌（Bacillus cereus）。若将筛选的该Bacillus cereus应用至浓香型白酒传统酿造工艺,将能够提升浓香型白酒的香味和品质。 

Selecting of functional Bacillus strain from omagari and fermented grains of Luzhou-flavor liquor

To isolate Bacillus strain from Luzhou-flavor liquor so that the flavor components could be improved, 55 strains of Bacillus were obtained in the omagari and fermented grains of Luzhou-flavor liquor in total in this study.Through screening, one strain producing high-yield ethyl hexanoate and low-yield propanol was screened out which was then named as YB-16. The produced ethyl hexanoate belonged to excellent strong liquor of the national standard and the produced propanol belonged to extra edible alcohol of the national standard. After strain morphology, physiological and biochemical characteristics, molecular biology assay and the constructed phylogenetic tree, YB-16 and Bacillus cereus strain CCM NBRC 15305 clustered into a branch and were each other's closest relatives.Thus, YB-16 was identified as Bacillus cereus.It is expected that the application of Bacillus cereus strain to the traditional brewing process of Luzhou-flavor liquor could improve its flavor and quality.