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IVES 9 IVES Conference Series 9 Observatoire Grenache en vallée du Rhône : démarche et premiers résultats après une année d’étude

Observatoire Grenache en vallée du Rhône : démarche et premiers résultats après une année d’étude

Abstract

Face à l’enjeu d’affirmer et de mieux comprendre la spécificité des vins en relation avec leur origine, la notion de « terroir », avec la richesse de sens et la diversité des perspectives qui l’éclairent, se révèle la clef de voûte de la production et de la valorisation de vins personnalisés et typiques. Asseoir la connaissance des principaux terroirs de la Vallée du Rhône sur des bases autres que celles, jusqu’alors essentiellement empiriques, invoquées dans la seconde grande région française productrice de vins d’AOC, constitue un projet conforme à l’intérêt voué à cet enjeu d’actualité. En effet, sous un angle technologique, le terroir viticole, considéré surtout comme « l’ensemble des facteurs du milieu naturel que le viticulteur ne peut ou ne pourra modifier aisément » (Laville, 1990), a déjà fait l’objet de nombreuses démarches pour la caractérisation de ses potentialités. Parmi les travaux entrepris, les approches « multicritères » cherchent à mettre en évidence les facteurs naturels du terroir les plus objectifs possibles en relation avec leurs effets mesurables sur les vins. Elles s’affinent généralement en fonction de données de « réponse » du terroir sous forme de critères doublement analytiques et sensoriels (Falcetti, Scienza, 1991).

L’une des méthodologies les plus complètes, celle dite de « caractérisation intégrée » et fondée sur la notion de séquence écogéopédologique (Morlat et al., 1984 ; Morlat, 1989), a été mise en oeuvre dans les vignobles d’Appellation d’Origine Contrôlée de la Moyenne Vallée de la Loire ; elle a abouti à la définition du concept d’Unité Naturelle de Terroir de Base (Riou et al., 1995). Reprise en Alsace (Lebon et al., 1993), la méthodologie de caractérisation intégrée se montre transposable. La multiplicité des données requises lors de l’initiation d’une telle approche requiert cependant un dispositif expérimental lourd et de longue haleine. Ainsi, la Vallée du Rhône se trouve actuellement le théâtre d’une double initiation de caractérisations multicritères des terroirs, appliquées aux vins rouges issus respectivement des cépages Syrah et Grenache.

En particulier, pour le cépage Grenache, majoritaire dans les vins de la partie méridionale, on dispose d’ores et déjà des observations de la campagne 1995, période qui correspond à la mise en place d’un dispositif de caractérisation multicritères. Pour le moment, il s’agit d’abord de mettre en évidence des différences de comportements de la vigne associées à des typologies de vins. Ensuite, dans la mesure où la jeunesse du dispositif le permet, la démarche vise à montrer que les typologies décrites s’édifient sur la base de la distinction de terroirs, uniques et véritables pourvoyeurs de spécificité, dans un réseau d’observations où l’on a veillé à maîtriser l’ensemble des autres facteurs de variabilité – système de conduite, porte-greffe, clones, itinéraires techniques, etc…

DOI:

Publication date: March 25, 2022

Issue: Terroir 1996

Type : Poster

Authors

E. VAUDOUR, L.M. BREMOND, L. LURTON

Institut rhodanien
2260, route du grés, 84100 Orange, France

Tags

IVES Conference Series | Terroir 1996

Citation

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