葡萄园土壤中酿酒酵母的分离鉴定及其发酵葡萄酒香气成分分析

从上海奉贤、上海崇明、上海松江、湖北武汉、浙江绍兴、山东菏泽、辽宁铁岭等地葡萄园土壤中，经过分离纯化，得到4 株酵母。通过26S rDNA D1/D2区域序列比对及构建系统发育树分析，结果表明：S1、S2、S3为酿酒酵母（Saccharomyces cerevisiae），S4为异常威克汉逊酵母（Wickerhamomyces anomalus）。采用顶空固相微萃取结合气相色谱-质谱联用，进一步对4?株酵母菌的发酵香气化合物进行测定，并以商业酵母发酵酒作为对照。结果表明，4?株酵母菌在葡萄糖酒发酵中的挥发性香气成分有所差别，相对于商业酵母，S1发酵酒中独有的香气化合物有十四酸乙酯、2-甲基丁醇、壬醛、癸醛、苯乙酮、1-十八烷烯等7?种，S2发酵酒中独有的香气化合物有十四酸乙酯、十六酸乙酯、丙三醇、正己醇、2-甲基己醇、右旋柠檬烯等10?种，S3发酵酒中乙醇含量明显高于商业酵母，S4发酵酒中苯乙醇和乙酸含量明显高于商业酵母。综合评价，S1、S2发酵酒的花香和果香更加突出，S3发酵酒具有较高的乙醇含量，S4发酵酒的乙酸含量最高。

Isolation and Identification of Yeast Strains from Vineyard Soils and Aroma Compounds of Wines Fermented by Them

Four strains of yeast, designated as S1, S2, S3 and S4, were isolated and purified from vineyard soils from Shanghai’s Fengxian, Chongming and Songjiang districts; Wuhan, Hubei province; Shaoxing, Zhejiang province; Heze, Shandong province; Tieling, Liaoning province. Phylogenetic tree analysis was carried out based on the 26S rDNA D1/D2 domain sequence. The results showed that S1, S2 and S3 were identified as Saccharomyces cerevisiae and S4 as Wickerhamomyces anomalus. The volatile aroma compounds of wines (W1, W2, W3 and W4) fermented by the four strains were determined by headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS), and commercial yeast served as control. It was found that the volatile aroma compounds of wines fermented by theses isolates were different. Seven aroma compounds including ethyl myristate, 2-methyl-1-butanol, nonyl aldehyde, capraldehyde, acetophenone and 1-octadecene were exclusively detected in wine S1 rather than in control wine, and 10 aroma compounds in wine S2, such as ethyl myristate, ethyl palmitate, glycerol, n-hexanol, 2-methyl-2-hexanol and d-limonene. Phenylethanol and phenylethanol were significantly more abundant in W4 than in the control. Overall, W1 and W2 had stronger floral and fruity aroma. W3 contained higher content of ethanol. The acetic acid content of W4 was the highest.