浓香型大曲中1株高发酵力芽孢杆菌的筛选和鉴定

摘要

The exploration on bacteria species resource in different Daqu-making stages could enrich liquor-making microbes re-source bank.In the experiment,plate preliminary screening and solid fermentation secondary screening were adopted to screen Bacil-lus strains with high fermenting power in different Daqu-making stage.Afterwards,16S rDNA identification was performed.And the correlativity between Bacillus stains and flavoring substances was investigated through HS-SPME-GC-MS analysis of the fermenting product of the screened strains.The results showed that,the fermenting power of X13 strain was as high as 0.49 g/0.5 g·72 h,which was in accord with quality level of traditional Daqu fermenting power,and it was identified as Bacillus velezensis.The solid-state fer-mentation of X13 strain could produce 17 kinds of volatile flavoring substances including pyrazines, phenolics, alcohols, aldehydes and esters etc.X13 strain was a Daqu functional strain.%通过研究浓香型大曲不同制曲阶段的菌种资源,以丰富白酒酿造的微生物资源库.采用平板初筛、固态发酵复筛,从不同制曲阶段筛选高发酵力芽孢杆菌,并进行16S rDNA鉴定.对优选菌株固态发酵产物采用HS-SPME-GC-MS方法初步探寻芽孢杆菌和风味物质之间的相关性.结果表明,编号X13菌株的发酵力为0.49 g/0.5 g·72 h,达到了传统大曲发酵力的优良等级,并鉴定其为贝莱斯芽孢杆菌(Bacillus velezensis);X13菌株固态发酵能产生17种挥发性风味物质,包括吡嗪类物质、酚类物质、醇类物质、醛类物质和酯类物质等,可初步确定为大曲功能菌株.