University of Bordeaux, Unité Mixte de Recherche 1366 Œnologie, ISVV, 33882 Villenave d'Ornon Cedex, France.
Pernod-Ricard, 75016 Paris, France.
J Agric Food Chem. 2022 Sep 21;70(37):11520-11530. doi: 10.1021/acs.jafc.2c00543. Epub 2022 Sep 6.
The goal of this study was to evaluate how grape composition modifications linked to maturity level could affect the wine ester composition and aromatic expression. An experimental design has been developed from grapes of cv Merlot and cv Tempranillo. On each vine plot, grapes have been harvested at two maturity levels and have been fermented using a commercial yeast strain under standardized conditions, specifically after having the sugar and nitrogen concentrations adjusted to the same target values. Tempranillo wine ester content was not impacted by the maturity level, whereas Merlot wines from the highest maturity level showed lower concentrations for fatty acid ethyl esters and higher alcohol acetates but higher concentrations for substituted ethyl esters. Sensory analysis corroborated these analytical results: when Merlot maturity increased, wine fruity aromatic expression decreased (particularly its global intensity and the fresh, red-berry, and fermentative fruit characters). In addition, aromatic reconstitution experiments showed that esters were not, alone, responsible for the sensory differences linked to grapes' maturity. Globally, our results highlight the role of esters in the overall wine fruity aromatic expression associated to Merlot ripeness and show that their levels are impacted by other parameters than the grape content in sugars and amino acids, well known as being their precursors.
本研究旨在评估与成熟度相关的葡萄成分变化如何影响葡萄酒酯类成分和香气表达。本研究采用梅洛（cv Merlot）和添普兰尼洛（cv Tempranillo）葡萄，设计了一项实验。在每个葡萄藤地块上，葡萄分两个成熟度进行采摘，并在标准化条件下使用商业酵母菌株进行发酵，具体做法是先将糖和氮浓度调整到相同的目标值。成熟度对 Tempranillo 葡萄酒酯含量没有影响，但最高成熟度的 Merlot 葡萄酒的脂肪酸乙酯浓度较低，高级醇乙酸酯浓度较高，但取代乙酯浓度较高。感官分析证实了这些分析结果：当梅洛成熟度增加时，葡萄酒的果香香气表达减弱（特别是其整体强度、新鲜、红色浆果和发酵水果特征）。此外，芳香再构成实验表明，酯类本身并不是与葡萄成熟度相关的感官差异的唯一原因。总体而言，我们的结果强调了酯类在与梅洛成熟度相关的葡萄酒整体果香香气表达中的作用，并表明其水平受到其他参数的影响，而不仅仅是葡萄中糖和氨基酸的含量，这两个参数是它们的前体。
