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IVES 9 IVES Conference Series 9 The influence of the soil on the phenolic composition of both grapes and wines : “the Grenache observatory”

The influence of the soil on the phenolic composition of both grapes and wines : “the Grenache observatory”

Abstract

[English version below]

La composition fine des raisins de Grenache noir est mal connue. Il est généralement admis une certaine variabilité de comportement de ce cépage qui se manifeste principalement sur la couleur des vins. De nombreux facteurs peuvent être à l’origine de cette variabilité : matériel végétal, pratiques culturales, types de vinification et terroir. Un travail de recherche concernant ce cépage a été engagé dans la Vallée du Rhône. L’étude a pour but de juger le comportement de ce cépage dans différentes situations pédoclimatiques. La couleur et les tanins des raisins et des vins issus des différents terroirs caractéristiques de la Vallée du Rhône sont analysés. L’utilisation de techniques analytiques performantes (C.L.H.P.) nous permet d’étudier dans le détail la composition anthocyanique des vins. Cette communication fait état des résultats relatifs à la couleur et aux tanins (analyses en spectrophotométrie UV-Visible) des raisins issus de douze parcelles du dispositif « Observatoire Grenache » sur quatre millésimes consécutifs. Cette étude nous a permis de mettre en évidence l’influence des millésimes sur les teneurs en anthocyanes (de 0.5 à 1.3 g/kg) et en tanins (de 6.2 à 11.5 g/kg), mais surtout l’impact du «terroir» sur les concentrations totales en polyphénols des raisins. La caractérisation fine, par Chromatographie Liquide Haute Performance, des vins correspondants confirme l’analyse des raisins, montrant également de fortes variations de la quantité globale en anthocyanes. Par contre, la nature et la structure des 7 anthocyanes dosées semblent peu affectées par le millésime et l’effet terroir. Le «profil anthocyanique » ainsi obtenu sur les vins reste caractéristique du cépage Grenache noir, quel que soit le millésime ou le terroir.

The detailed composition of the Grenache vine variety is not well known. A slight variability in the nature of this vine variety is generally accepted which principally appears on the color of the wine. Many factors can be the source of this variability like the vegetal material, the growing cultural practices, the type of winemaking and soil. A research work concerning this vine variety has started in the Rhône Valley. The purpose of this study is to evaluate the vine variety behavior placed in various pedoclimatic conditions. The color and the tannins of both wines and grapes, from various characteristic soils of the Rhône Valley, are analyzed. The use of performing analytical technics (H.P.L.C.) provides us a way to study with great detail the anthocyanic composition of the wines. This presentation states results associated with the color and the tannins (UV-visible spectrophotometry analysis) of grapes, coming from twelve lots of the “Grenache Observatory” over four consecutive vintages. Thanks to this study, we were able to point out the influence of the vintage on the concentration of both anthocyanins (from 0.5 to 1.3 g/kg) and tannins (from 6.2 to 11.5 g/kg) and even more, it showed the impact of the soil on the total polyphenol concentration of the grape. A detailed analysis by High Performance Liquid Chromatography, of the corresponding wines, confirms the grapes analysis, which shows consequent variation of the global anthocyanin quantity. However, the nature and the structure of the 7 analyzed anthocyanins do not seem to be significantly dependent on either the vintage or the soil. The obtained anthocyanic profile of the wines still remains specific to the black grenache vine variety and it does not depend on the vintage or the soil.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

PUECH C. (1), ORMIERES J-F. (1), SIPP C. (2), JACQUET O. (3), RIOU C. (1)

(1) Service Technique d’Inter Rhône
(2) Syndicat Général des Vignerons Réunis des Côtes du Rhône
(3) Chambre d’ Agriculture du Vaucluse – Institut Rhodanien, 2260 Route du Grès, 84000 Orange, France

Contact the author

Keywords

terroir, anthocyanes, tanins, Grenache noir
soil, anthocyanins, tannins, Grenache

Tags

IVES Conference Series | Terroir 2002

Citation

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