桑葚酒用非酿酒酵母的筛选及特性研究

Screening and characterization of non-Saccharomyces for mulberry wine

为筛选出适合桑葚酒发酵的非酿酒酵母,改善桑葚酒的口感及香味,以桑葚及桑园土壤样品中筛选得到的72株酵母菌为出发菌株,经杜氏管发酵、酒精发酵与感官品评进行初筛。将初筛得到的酵母分别与酿酒酵母(Saccharomyces cerevisiae)BO213按1∶1的比例接种到桑葚汁中发酵,通过感官品评与理化分析优选出一株非酿酒酵母JM-7,经鉴定该酵母为异常威克汉逊酵母(Wickerhamomyces anmalus)。其与菌株BO213混酿的桑葚酒感官评分为90.2分,总酯含量为3.21 g/L,还原糖含量为3.9 g/L,酒精度、总酸、挥发酸含量分别为11.7%vol、7.97 g/L、0.51 g/L。研究菌株JM-7生长曲线及耐受性发现,该酵母生长速率快,5 h即进入对数期,36 h达到稳定期,最高菌体浓度为4.5×10^(8)CFU/mL,对温度、pH、SO_(2)都有较好的耐受性,在16~36℃、pH 2~10、SO_(2)质量浓度0~100 mg/L均能正常生长,但对酒精的耐受性较差,在酒精度为8%vol时生长受到抑制,在12%vol时不能生长。

In order to screen the non-Saccharomyces suitable for mulberry wine fermentation and improve the taste and aroma of mulberry wine,using 72 yeast strains screened from mulberry and mulberry garden soil samples as starting strains,the primary screening was conducted through Duchenne tube fermentation,alcohol fermentation and sensory evaluation.The screened yeast and the Saccharomyces cerevisiae BO213 were inoculated into mulberry juice with the ratio of 1∶1,respectively.A non-Saccharomyces strain JM-7 was screened by sensory evaluation and physicochemical analysis,and the yeast was identified as Wickerhamomyces anomalus.The sensory score of mulberry wine by mixed fermentation with strain BO213 and strain JM-7 were 90.2,the total ester content was 3.21 g/L,the reducing sugar content was 3.9 g/L;and the alcohol content,total acid and volatile acid were 11.7%vol,7.97 g/L and 0.51 g/L,respectively.The growth curve and tolerance of strain JM-7 showed that the growth rate of the yeast was fast,the logarithmic phase was entered at 5 h and reached stable phase at 36 h,and the maximum bacterial concentration was 4.5×10^(8)CFU/ml.The strain showed good tolerance to temperature,pH and SO_(2)and could grow normally at 16-36℃,pH 2-10 and SO_(2)concentration 0-100 mg/L.However,the alcohol tolerance of the strain was poor,the growth was inhibited with alcohol content 8%vol,which could not grow at 12%vol.