酱香大曲中地衣芽孢杆菌及其特征风味代谢产物的分析研究

从酱香型酒生产用的高温大曲中筛选到三株产酱香的革兰氏阳性杆菌,有芽孢,兼性厌氧。经形态学、生理生化特性和16S rDNA序列分析,鉴定其为地衣芽孢杆菌(Bacillus licheniformis)。初步探索这三株细菌液态培养的最适条件,以麸皮浸出汁为培养基,150 r/min 55℃发酵6d,产生明显的酱香香气。从发酵液中检测到的乙偶姻、四甲基吡嗪和呋喃扭尔,是产酱香细菌发酵产生的特征性产物。

Analysis of characteristic metabolic products of Bacillus licheniformis isolated from Daqu of soy sauce aroma style

Three strains of bacteria producing sauce flavor were screened from daqu. They are gram-positive, facultative anaerobic, and produce cylinderical spores. Through analysis of morphology, physiological and biochemical characteristics and 16S rDNA sequencing, three strains were identified as Bacillus licheniformis. The culture conditions of three strains in submerged fermentation were optimized primarily. After three strains were inoculated in wheat extract medium and cultured at 55 ＂C for 6 d with an agitation speed of 150 r/min, fermentation liquid produced sauce flavor. Acetoin, tetramethylpyrazine and furaneol were detected in the fermentation broth and were identified as characteristic products of the strains producing sauce flavor.