酱曲中耐盐产香酵母的分离及其发酵特性

Isolation of Salt-tolerant and Aroma-producing Yeasts from Soybean Paste Starter and Their Fermentation Characteristics

从豆酱曲中分离出2株耐盐产香酵母,分别命名为Waro03和Saro47。26S rDNA测序表明这2株分别为异常威克汉姆酵母和酿酒酵母。2种酵母都表现出优良的pH值和氯化钠的耐受性,菌株Waro03能够在含14%NaCl培养基中很好地生长,而菌株Saro47及商业鲁氏酵母AS2.180则只能在含12%NaCl的培养基中很好地生长。产香特性分析表明Saro47菌株大量生产醇类、酯类、醛类及酸类物质;Waro03菌株大量生产酯类、醇类、酚类及酸类物质。NaCl能够明显抑制Waro03产生醇类、酯类及呋喃酮类物质,但是醛类、酸类及酚类物质的产生明显增加。对于异常威克汉姆酵母Waro03,NaCl能够抑制醇产生,如3-甲基-1-丁醇和苯乙醇,但是乙醇的产生不受影响。Saro47菌株与商业用鲁氏酵母有相似的产香特性和耐盐反应。同时,结果也表明由于Waro03菌株具有良好的耐盐和产酯能力,在酱油和酱制品发酵具有较好的应用潜力。

In the present study,two salt-tolerant and aroma-producing yeast strains,named Waro03 and Saro47,were isolated from soybean paste starter.Ribosomal DNA sequencing indicated that they were highly homologous with Wickerhamomyces anomalus and Saccharomyces cerevisiae,respectively.Both strains showed good pH and NaCl resistance.Waro03 showed good growth in the medium containing 14%NaCl(m/m)whereas Saro47 and commercial Zygosaccharomyces rouxii AS2.180 could grow well only in the medium containing 12%NaCl(m/m).Saro47 produced large amounts of alcohols,esters,aldehydes and acids,while Waro03 produced large amounts of esters,alcohols,phenols and acids.NaCl could significantly inhibit the production of alcohols such as 3-methyl-1-butanol and phenylethyl alcohol,esters and furanones by Waro03,but significantly increased the production of aldehydes,acids and phenols.NaCl did not affect ethanol production.Saro47 showed similar aroma-producing characteristics and NaCl tolerance to AS2.180.The results of this study suggested that W.anomalus Waro03 looks promising as a starter culture for soy sauce and paste fermentation due to its capability of producing esters and tolerance to salts.