咖啡果优良本土酵母菌筛选及发酵特性

Screening and Fermentation Characterization of Elite Indigenous Yeast Strains for Coffee Pulp

为筛选咖啡果果酒优良酵母菌,该研究从咖啡果发酵液中分离纯化获得109株酵母菌,经形态鉴定去重复获得27株酵母菌,通过研究酵母菌的产气能力、产乙醇能力、产酯能力、产H2S能力及嗜杀性筛选到3株优良酵母菌,分别编号为WRJ-20、WRJ-34、WRJ-37。耐受性试验表明,当温度达到40℃时,WRJ-34还能正常生长具有较好的温度耐受性;当pH值为3.0~3.5时,3株菌均可正常生长,具有较好的pH耐受性;3株酵母菌均能耐受400 g/L葡萄糖浓度;菌株WRJ-20的SO2耐受性最好;菌株WRJ-20有较好的乙醇耐受性。经分子生物学鉴定,WRJ-20为异常威克汉姆酵母(Wickerhamomyces anomalus),WRJ-37为泽普林假丝酵母(Starmerella bacillaris),WRJ-34为酿酒酵母(Saccharomyces cerevisiae)。3株酵母菌均具有良好的发酵性能、耐受性、嗜杀性等酿造学特性,可用于果酒的酿造。

With the aim of screening elite yeast strains for wine production by fermentation of coffee pulp,109 yeast strains were isolated from the fermentation broth of coffee pulp.After morphological identification and de-duplication,27 yeast strains were obtained.By evaluation of the gas production,ethanol production,ester pro-duction,H2S production,and killer activity,three yeast strains were screened out and designated as WRJ-20,WRJ-34,and WRJ-37.Tolerance tests indicated that WRJ-22 exhibited good thermal stability and grew nor-mally at 40℃.All the three strains grew normally within the pH range of 3.0 to 3.5,demonstrating good pH tol-erance.All the three yeast strains could tolerate 400 g/L glucose.Strain WRJ-20 showed the best tolerance to SO2 and good tolerance to ethanol.According to the molecular evidence,WRJ-20,WRJ-37,and WRJ-34 were identified as Wickerhamomyces anomalus,Starmerella bacillaris,and Saccharomyces cerevisiae,respectively.All the three yeast strains exhibited excellent fermentation performance,tolerance,and killer activities,being suitable for fruit wine brewing.