自然发酵猕猴桃果酒中降苹果酸酵母的筛选与鉴定  

Screening and identification of malic acid-reducing yeast in naturally fermented kiwifruit wine

作　　者：周清丽 周绍琴 周艳[1] ZHOU Qingli;ZHOU Shaoqin;ZHOU Yan(School of Public Health,Guizhou Medical University,Guiyang 550025,China)

机构地区：[1]贵州医科大学公共卫生与健康学院,贵州贵阳550025

出　　处：《中国酿造》2023年第12期76-80,共5页China Brewing

基　　金：贵州省普通高等学校青年科技人才成长项目(黔教合KY字[2022]216号)。

摘　　要：该研究以自然发酵猕猴桃果酒中分离得到的7株低产醇酵母菌(编号为YK1~YK7)为研究对象,通过测定其在含有10 g/L苹果酸的酵母浸出粉胨葡萄糖(YPD)培养基中培养后的pH值及总酸含量,筛选具有降苹果酸的酵母菌。利用筛选菌株发酵制备猕猴桃果酒,研究其对猕猴桃果酒降酸、降醇效果,并通过形态学观察、生理生化鉴定及分子生物学技术对其进行菌种鉴定。结果表明,筛选得到5株具有苹果酸降解能力的酵母菌株(YK1、YK2、YK3、YK5、YK6),总降酸率为32.45%~48.76%。采用这5株酵母菌株发酵制备猕猴桃果酒,总酸、苹果酸含量均下降,总降酸率为3.56%~15.67%,苹果酸降酸率为25.90%~33.02%。经鉴定,菌株YK1、YK2、YK5与YK6为异常威克汉姆酵母(Wickerhamomyces anomalus),菌株YK3为酿酒酵母(Saccharomyces cerevisiae)。其中,菌株YK6降苹果酸效果最好,其发酵制备的猕猴桃果酒pH为3.66,总酸含量为10.58 g/L,苹果酸含量为3.40 g/L,酒精度为2.2%vol,说明菌株YK6可作为酿造低酸、低醇猕猴桃果酒的优良酵母。In this study,seven low-alcohol producing yeasts(numbered as YK1-YK7) isolated from naturally fermented kiwifruit wine were selected as the research object,and the yeast with reduced malic acid was screened by determining the pH value and total acid content after cultured in yeast extract peptone dextrose(YPD) medium containing 10 g/L malic acid.Kiwifruit wine was prepared by fermentation of the selected strain,and its effect on acid and alcohol reduction was studied.The strain was identified by morphological observation,physiological and biochemical identification and molecular biology techniques.The results showed that five yeast strains(YK1,YK2,YK3,YK5,YK6) with malic acid degradation ability were screened,and the total acid reduction rate was 32.45%-48.76%.Using these five yeast strains to prepare kiwi fruit wine,the contents of total acid and malic acid decreased,the total acid reduction rate was 3.56%-15.67%,and the acid reduction rate of malic acid was 25.90%-33.02%.Strains YK1,YK2,YK5 and YK6 were identified as Wickerhamomyces anomalus,and strain YK3 was Saccharomyces cerevisiae.Among them,strain YK6 had the optimal effect on reducing malic acid.The p H of kiwifruit wine fermented by the strain YK6 was 3.66,the total acid content was 10.58 g/L,the malic acid content was 3.40 g/L and alcohol content was 2.2%vol,indicating that the strain YK6 could be used as an excellent yeast for brewing low-acid and low-alcohol kiwifruit wine.

关 键 词：降酸 筛选 苹果酸 猕猴桃果酒 生物降酸 

分 类 号：TS262.1[轻工技术与工程—发酵工程]