新疆慕萨莱思自然发酵过程中酵母菌表型多样性及优势菌分析

Phenotype Diversity and Dominant Species of Yeasts during Spontaneous Fermentation Process of Musalais from Xinjiang

目的:研究新疆慕萨莱思自然发酵过程中酵母菌种群表型多样性与其优势菌,探讨慕萨莱思传统工艺对其主要菌群结构的影响。方法:来自于新疆阿瓦提一古作坊的慕萨莱思酿制原料、原料处理液及发酵液(自然发酵过程中)共19份样品被用于酵母菌分离,分离株利用WL培养基培养归类,筛选代表株,对代表株进行形态观察、生理生化特征检测与类平均连算法聚类分析,探讨新疆慕萨莱思自然发酵过程中酵母菌表型多样性及优势菌群。结果:分离得到217株酵母菌,13种WL培养类型,8个表观群。13株代表菌株经初步鉴定为7个属,疑似为13个种,表明慕萨莱思酵母菌具有丰富的多样性。Hanseniaspora spp.为葡萄果皮、果汁及皮渣中的优势菌,S.cerevisiae为慕萨莱思自然发酵过程中起发者及唯一一种优势菌,非酿酒酵母偶尔在发酵液中发现。结论:慕萨莱思酿制过程中,葡萄原料原有的酵母菌经熬煮工序几乎被全部杀死,自然发酵中唯一优势菌S.cerevisiae可能来自酿制场所和设备,并具有较高适应能力。

Objective： To investigate the phenotype diversity and dominant species of yeasts during spontaneous fermentation process of Musalais from Xinjiang, and explore the effect of traditional technology on yeast community. Methods： A total of 19 samples were collected from the traditional spontaneous fermentation process of Musalals （including grapes, grape juice, boiled juice and fermentation broth） to analyze yeast phenotype diversity and corresponding dominant species. The isolated strains from these samples were typed and representative strains were selected for colony characteristic analysis on Wallerstein laboratory nutrient agar （WL nutrient agar） and grouped by unweighted pair group method with arithmetic mean （UPGMA） method and primarily identified according to their morphological and physiological characteristics. Results： Totally 217 isolates, 13 types based on WL agar culture, and 8 phenotype groups from 13 representative strains were harvested. Meanwhile, 7 generaand 13 species were primarily identified. The diversity of yeasts was associated with spontaneous fermentation of Musalais. Hanseniaspora spp. was the dominant strain in grape skin, grape juice and boiled grape juice. Saccharomyces cerevisiae is a starter and the only dominant strain during spontaneous fermentation of Musalais; however, other yeast species were also occasionally observed in fermentation broth. Conclusion： Almost all yeasts from grapes are killed by boiling during the production of Musalais. S. cerevisiae may come from brewing utensils and locations, and has high adaptability to spontaneous fermentation of Musalais.