Abstract：
Hanseniaspora vineae exhibits extraordinary positive oenological characteristics contributing to the aroma and texture of wines, especially by its ability to produce great concentrations of benzenoid and phenylpropanoid compounds compared with conventional Saccharomyces yeasts. Consequently, in practice, sequential inoculation of H. vineae and Saccharomyces cerevisiae allows to improve the aromatic quality of wines. In this work, we evaluated the impact on wine aroma produced by increasing the concentration of phenylalanine, the main amino acid precursor of phenylpropanoids and benzenoids. Fermentations were carried out using a Chardonnay grape juice containing 150 mg N/L yeast assimilable nitrogen. Fermentations were performed adding 60 mg/L of phenylalanine without any supplementary addition to the juice. Musts were inoculated sequentially using three different H. vineae strains isolated from Uruguayan vineyards and, after 96 h, S. cerevisiae was inoculated to complete the process. At the end of the fermentation, wine aromas were analysed by both gas chromatography-mass spectrometry and sensory evaluation through a panel of experts. Aromas derived from aromatic amino acids were differentially produced depending on the treatments. Sensory analysis revealed more floral character and greater aromatic complexity when compared with control fermentations without phenylalanine added. Moreover, fermentations performed in synthetic must with pure H. vineae revealed that even tyrosine can be used in absence of phenylalanine, and phenylalanine is not used by this yeast for the synthesis of tyrosine derivatives.
摘要：
Hanseniasporavineae表现出非凡的积极的酿酒特性，有助于葡萄酒的香气和质地，特别是与常规酵母相比，它能够产生高浓度的苯类和苯丙素化合物。因此,在实践中,连续接种H.vineae和酿酒酵母可以提高葡萄酒的香气质量。在这项工作中,我们评估了增加苯丙氨酸浓度对葡萄酒香气的影响，苯丙素类和苯类的主要氨基酸前体。使用含有150mgN/L酵母可同化氮的霞多丽葡萄汁进行发酵。进行发酵,添加60mg/L的苯丙氨酸而不向果汁中添加任何补充。使用从乌拉圭葡萄园分离的三种不同的H.vineae菌株依次接种Musts，96小时后，接种酿酒酵母以完成该过程。在发酵结束时,通过气相色谱-质谱法和通过专家小组的感官评估来分析葡萄酒的香气。源自芳香族氨基酸的香气根据处理而不同地产生。与不添加苯丙氨酸的对照发酵相比，感官分析显示出更多的花特性和更大的芳香复杂性。此外，发酵在合成必须与纯H.vineae显示，即使酪氨酸可以在没有苯丙氨酸的情况下使用，这种酵母不使用苯丙氨酸合成酪氨酸衍生物。
