酱香大曲中可培养的冠突散囊菌的初步研究

Primary study on the cultivable Eurotium cristatus in Moutai-flavor Daqu

采用平板涂布法从酱香大曲中分离筛选霉菌,结合形态观察和真菌16S rDNA-ITS基因序列同源性比对分析,对筛选到的菌株进行鉴定。根据大曲功能和散囊菌特点,测定该菌酶活力;采用固相微萃取-气质联用技术对固态发酵的挥发性香味物质进行分析。筛选分离得到一株散囊菌,归类并命名为冠突散囊菌(Eurotium cristatus),该菌的酸性蛋白酶、脂肪酶、果胶酶酶活力较高,分别为594.62 U/g,45.29 U/g和410.26 U/g;固态发酵物具有花香和果菜香,挥发性香味物质以高级醇、酮和呋喃类为主体,其中L-芳樟醇、1-辛烯-3-醇、3-辛酮、2-戊基呋喃是主要的呈香物质。分离得到的冠突散囊菌的产酶特点和产香功能反映了霉菌在酱香型大曲中的重要作用。

Molds were screened from Moutai flavor Daqu, and then identified by dilution plate coating method, combining with morphology observa- tion and fungal 16SrDNA-ITS gene sequence homology comparison analysis. According to the function of Daqu and the characteristics of Eurotium sp., the enzyme activity of the strain was determined. Using SPME-MS technique, the volatile substances of the solid-state fermentation were ana- lyzed. The results showed that a Eurotium cr/status was screened, and the enzyme activity of its acid protease, lipase, pectinase were 594.62 U/g, 45.29 U/g and 410.26 U/g, respectively. The substances of solid-state fermentation of the strain has floral and fruity flavor, and the main volatile fla- voring substances were mainly higher alcohols, ketones, and furan. L-linalool, 1-octene-3-alcohol, 3-symplectic ketones and 2-amyl furan were the dominating aroma-producing substance. The enzyme production characteristics and aroma production fi.mction of the isolated E. cristatus reflected the important role of mold in Moutai-flavor Daqu.