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IVES 9 IVES Conference Series 9 Contribution du potentiel glycosidique à l’arôme des vins de Grenache noir et Syrah en Vallée du Rhône

Contribution du potentiel glycosidique à l’arôme des vins de Grenache noir et Syrah en Vallée du Rhône

Abstract

Grenache Noir and Syrah are the predominant grape varieties in the French Rhone valley vineyard, and produce wines with well differentiated aromatic notes. This study aimed at investigating the contribution of glycoconjugated precursors to these aromatic specificities, through their analytical profiles and the sensory influence of the odorant compounds they release during wine aging. The aglycones released by enzymatic hydrolysis of glycosidic extracts from grape were quantified using GC-MS analysis, and the profiles of both varieties were compared for different geographical sites of the French Rhone valley vineyard, and for three consecutive years. Moreover, the wines elaborated with different grapes were added with their own glycosides, then submitted to aging treatments prior to sensory descriptive analysis. The results showed that addition with glycosidic precursors enhanced the initial aromatic notes of the wines, depending on grape variety and vine site. The aglycone profiles of the grapes of the two varieties showed significant differences for half of the quantified compounds, and were influenced by vintage and vine site. It therefore appeared that glycosidic precursors could actually contribute to the aging aromas of Grenache Noir and Syrah wines, and to the complex interactions between variety and terroir.
Le Grenache Noir et la Syrah sont les cépages les plus répandus dans le vignoble français de la vallée du Rhône, et produisent des vins bien différenciés d’un point de vue aromatique. L’objectif de cette étude est de cerner la contribution des précurseurs glycosidiques à ces spécificités aromatiques, à travers leurs profils analytiques et l’influence sensorielle des composés odorants qu’ils génèrent au cours du vieillissement des vins. Les aglycones libérées par hydrolyse enzymatique des extraits glycosidiques des baies ont été quantifiées par analyse en GC-MS, et les profils des deux variétés ont été comparés pour différents terroirs de la vallée du Rhône, et trois millésimes consécutifs. Par ailleurs, les vins élaborés à partir de ces raisins ont été enrichis en leurs propres précurseurs, puis soumis à des traitements de vieillissement avant une analyse sensorielle descriptive. Les résultats montrent que l’enrichissement en glycosides intensifie les notes aromatiques initiales des vins, avec un effet dépendant du cépage et du site d’implantation de la vigne. Les profils d’aglycones des baies des deux variétés présentent des différences significatives portant sur la moitié des composés quantifiés, et apparaissent influencés par le millésime et le site d’implantation. Cette étude montre ainsi que les précurseurs glycosidiques pourraient participer à l’arôme de vieillissement des vins de Grenache Noir et Syrah, et aux interactions complexes entre cépage et terroir.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

M. Ségurel (1,2), R. Baumes (1), C. Riou (2), A. Razungles (1)

(1) UMR Sciences pour l’œnologie, INRA, 2 place Viala, 34060 MONTPELLIER Cedex 1
(2) INTER RHONE, Interprofession des vins AOC Côtes-du-Rhône et vallée du Rhône, 2260 route du Grès, 84100 ORANGE

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Keywords

Wine, grape, Grenache noir, Syrah, aroma, glycoconjugate, sensory analysis, volatile

Tags

IVES Conference Series | Terroir 2004

Citation

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