西藏青稞小曲中优良微生物的筛选与鉴定

Screening and identification of excellent microorganisms in Tibetan highland barley Xiaoqu

为生产具有西藏地区特色的青稞小曲产品,确保青稞酒产品风味的稳定性,采用传统培养法对收集的21个青稞小曲样品中的微生物进行分离纯化和分子生物学鉴定,利用透明圈法初筛和制曲复筛选择优良菌株。结果表明,西藏青稞小曲中共分离出278株菌,主要包括蜡样芽孢杆菌、沙福芽孢杆菌、短小芽孢杆菌、苏云金芽孢杆菌、解淀粉芽孢杆菌和 Kocuria marina 6种细菌,扣囊复膜孢酵母、酿酒酵母、 Saccharomycopsis malanga 、米根霉、卷枝毛霉、总状毛霉、白囊耙齿菌、伞状毛霉菌、米曲霉、黄曲霉、黑曲霉、 Coriolopsis trogii 和毛栓菌13种真菌。复筛得到糖化力为(1382±77.38)mg/(g·h)的米根霉M12,中性蛋白酶活力为(1 035.56±40.09)μg/(g·min)的解淀粉芽孢杆菌Q4。该研究结果为优化制曲工艺和提升青稞酒品质提供了研究基础。

This study aimed to produce highland barley Xiaoqu products with Tibetan characteristics while ensuring flavor stability of highland barley wine products. The traditional culture method was used to separate, purify and identify microorganisms collected from21 highland barley Xiaoqu samples, followed by transparent circle and starter-making screening. The results showed that a total of278 strains were isolated and purified from Tibetan highland barley Xiaoqu , including six species of bacteria: Bacillus cereus, Bacillus safensis, Bacillus pumilus, Bacillus thuringiensis, Bacillus amyloliquefaciens , and Kocuria marina . Besides, there were13 fungi identified, including Saccharomycopsis fibuligera, Saccharomyces cerevisiae, Saccharomycopsis malanga, Rhizopus oryzae, Coriolopsis trogii, Mucor circinelloides, Mucor racemosus, Irpex lacteus, Lichtheimia corymbifera, Aspergillus oryzae, Aspergillus flavus, Aspergillus niger , and Trametes hirsute. R. oryzae M12 with a saccharifying power of (1382±77.38) mg/(g·h) and B. amyloliquefaciens Q4 with a protease activity of (1 035.56±40.09)μ g/(g·min) were obtained by secondary screening. This study provides a research basis for optimizing starter-making process and improving the quality of highland barley wine.