西藏传统青稞酒酿造用藏曲中主要酵母菌的分离及酿造特性研究

采用WL酵母形态鉴别培养基从不同地域来源藏曲中分离筛选出48株典型酵母形态菌株,进一步通过分子鉴定为酿酒酵母(Saccharomyces cerevisiae)31株,扣囊复膜孢酵母(Saccharomycopsis fibuliger)9株,Saccharomycopsis malanga 3株。通过青稞汁培养基发酵研究了不同种类酵母的酿造性能,发现酿酒酵母是青稞酒发酵主要产酒微生物,S.malanga是主要产酸微生物。通过26种香气代谢物的分析比较3种酵母产香性能发现酿酒酵母是青稞酒发酵主要产香微生物,能够产丰富的酯类、醇类和有机酸类香气物质,扣囊复膜孢酵母也对青稞酒中微量香气物质具有重要贡献,而S.malanga产香能力较弱。该文系统研究了西藏传统酿造青稞酒酿造用藏曲中主要酵母菌的酿造性能和风味功能,对青稞酒酿造风味品质的科学控制提供了依据。

Isolation of yeast strains from Zangqu of traditional Tibetan Qingke(highland barley)wine brewing and the oenological properties

Using the WL yeast morphological identification medium,a total of 48 strains of typical yeast morphology were isolated and identified from Zangqu(traditional koji for brewing Qingke wine)of different regions.Further,31 Saccharomyces cerevisiae strains,nine Saccharomycopsis fibuliger strains and three Saccharomycopsis malanga strains were identified by molecular identification.The brewing performance of different yeasts was studied by fermentation in Qingke culture medium.It was found that S.cerevisiae was the main alcohols producing microorganism in Qingke wine fermentation.While S.malanga was the main organic acid producing microorganism.Through the analysis of 26 aroma metabolites and comparison of three kinds of yeasts,it was found that S.cerevisiae was the main aroma producing microorganism in Qingke wine,which produced abundant esters,alcohols and organic acids.S.fibuliger had important contribution to trace aromatic substances in Qingke wine,however Saccharomycopsis malanga has weak ability to produce aroma compounds.This paper systematically studied the brewing performance and flavor function of the main yeasts in Zangqu for traditional Qingke wine brewing,and provided a basis for the scientific control of the flavor quality of Qingke wine.