Martin Valentina, Boido Eduardo, Giorello Facundo, Mas Albert, Dellacassa Eduardo, Carrau Francisco
Sección Enología, Departamento de Ciencia y Tecnologá de los Alimentos, Facultad de Quimica, Universidad de la República, Montevideo, Uruguay.
Departamento de Bioquímica y Biotecnología, Universitat Rovira I Virgili, Tarragona, Spain.
Yeast. 2016 Jul;33(7):323-8. doi: 10.1002/yea.3159. Epub 2016 May 3.
In several grape varieties, the dominating aryl alkyl alcohols found are the volatile group of phenylpropanoid-related compounds, such as glycosylated benzyl and 2-phenylethyl alcohol, which contribute to wine with floral and fruity aromas after being hydrolysed during fermentation. Saccharomyces cerevisiae is largely recognized as the main agent in grape must fermentation, but yeast strains belonging to other genera, including Hanseniaspora, are known to predominate during the first stages of alcoholic fermentation. Although non-Saccharomyces yeast strains have a well-recognized genetic diversity, understanding of their impact on wine flavour richness is still emerging. In this study, 11 Hansenisapora vineae strains were used to ferment a chemically defined simil-grape fermentation medium, resembling the nutrient composition of grape juice but devoid of grape-derived secondary metabolites. GC-MS analysis was performed to determine volatile compounds in the produced wines. Our results showed that benzyl alcohol, benzyl acetate and 2-phenylethyl acetate are significantly synthesized by H. vineae strains. Levels of these compounds found in fermentations with 11 H. vineae different strains were one or two orders of magnitude higher than those measured in fermentations with a known S. cerevisiae wine strain. The implications for winemaking in response to the negative correlation of benzyl alcohol, benzyl acetate and 2-phenylethyl acetate production with yeast assimilable nitrogen concentrations are discussed. Copyright © 2016 John Wiley & Sons, Ltd.
在几个葡萄品种中，发现占主导地位的芳基烷基醇是苯丙烷类相关化合物的挥发性基团，如糖基化的苄醇和2-苯乙醇，它们在发酵过程中水解后为葡萄酒带来花香和果香。酿酒酵母在很大程度上被认为是葡萄汁发酵的主要微生物，但已知包括汉逊酵母属在内的其他属的酵母菌株在酒精发酵的第一阶段占主导地位。尽管非酿酒酵母菌株具有公认的遗传多样性，但对它们对葡萄酒风味丰富度影响的了解仍在不断涌现。在本研究中，使用11株葡萄汁有孢汉逊酵母菌株发酵一种化学成分明确的类似葡萄的发酵培养基，该培养基类似于葡萄汁的营养成分，但不含葡萄衍生的次生代谢物。通过气相色谱-质谱联用（GC-MS）分析来测定所产葡萄酒中的挥发性化合物。我们的结果表明，苄醇、乙酸苄酯和乙酸2-苯乙酯是由葡萄汁有孢汉逊酵母菌株显著合成的。在11株不同葡萄汁有孢汉逊酵母菌株发酵中发现的这些化合物的含量比在已知酿酒酵母葡萄酒菌株发酵中测得的含量高一个或两个数量级。本文讨论了苄醇、乙酸苄酯和乙酸2-苯乙酯产量与酵母可同化氮浓度呈负相关对酿酒的影响。版权所有© 2016约翰威立父子有限公司。
