四川麸醋中高产生料淀粉水解酶菌株的分离筛选及应用研究

Isolation,Screening and Application of High-Yield Raw Starch Hydrolase Strains from Sichuan Bran Vinegar

淀粉熟化是当前酿造工业生产的必要环节,费时耗能,与当前资源节约、绿色环保、节约粮食的时代主题相悖。水解生料淀粉的微生物在四川麸醋酿造过程中扮演着重要角色。因此,该研究从四川麸醋醋醅中分离筛选出一株产生料淀粉酶的革兰氏阳性杆状菌Bacillus funiculus A2,在BPA培养基中30℃培养16 h即可达到稳定期,能在69℃范围内生长,其乙醇耐受性为9%,最低生长pH为3.5。通过模拟四川麸醋生产工艺进行醋醅发酵,探究Bacillus funiculus A2接种量对麸醋理化性质的影响。结果表明,接种Bacillus funiculus A2对醋醅水分含量、pH、总酸含量和还原糖含量的影响较小;增大接种量可促进醋醅发酵体系乙醇快速消耗,提高醋醅发酵的淀粉利用率。该研究为四川麸醋酿造的提质降耗和工艺改进提供了理论依据。

Starch ripening is a necessary link in the current brewing industry production,which is time-consuming and energy-consuming and contradicts the current theme of resource conservation,green environmental protection and grain conservation.Microorganisms that hydrolyze raw starch play an important role in the brewing process of Sichuan bran vinegar.Therefore,in this study,a Gram-positive rod-shaped bacterium Bacillus funiculus A2 which produces raw amylase is isolated and screened from the fermented grains of Sichuan bran vinegar.This strain reaches a stable stage after being cultured at 30℃for 16 h in BPA medium and could grow in the range of 69℃,and its ethanol tolerance is 9%and the minimum growth pH is 3.5.The effects of Bacillus funiculus A2 inoculation amount on the physicochemical properties of bran vinegar are studied by simulating the production process of Sichuan bran vinegar.The results show that inoculation of Bacillus funiculus A2 has little effect on moisture content,pH,total acid content and reducing sugar content in fermented grains,and the increase of inoculation amount could promote the rapid consumption of ethanol in the fermentation system of vinegar grains and improve the utilization rate of starch in fermentation of vinegar grains.This study has provided a theoretical basis for improving the quality,reducing the consumption and improving the process of Sichuan bran vinegar brewing.