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IVES 9 IVES Conference Series 9 Influence of the “terroir” (soil, climate and wine grower) on the quality of red Grenache wines in the Rhône Valley

Influence of the “terroir” (soil, climate and wine grower) on the quality of red Grenache wines in the Rhône Valley

Abstract

[English version]

«L’Observatoire Grenache» est un réseau de parcelles qui a été mis en place par l’Institut Rhodanien en Vallée du Rhône sur les millésimes de 1995 à 1999. Composé de 24 parcelles de Vitis vinifera L. cv Grenache noir, ce réseau vise à étudier l’influence du terroir (sol, climat et vigneron) sur la qualité des vins. Les parcelles ont été choisies afin de représenter différentes situations géographiques et géopédologiques de la vallée du Rhône. Le matériel végétal (clone, porte-greffe), la taille (cordon de Royat), la densité et l’âge de la parcelle ont été encadrées. Ainsi les conditions de milieu (sol, climat) et les pratiques du vigneron étaient les principales sources de variations. Cette étude a permis de montrer que les paramètres du milieu conditionnent la qualité de la matière première et des vins principalement sur les caractères organoleptiques. Les types de sol ont un rôle non négligeable lié à la mise à disposition de l’eau pour la vigne. Ils définissent ainsi un potentiel de croissance et de vigueur. Lorsque cette dernière est élevée, elle est défavorable à la qualité des vins.

Les composantes climatiques (températures et précipitations) ont été approchées au travers de suivis de températures à la parcelle et de relevés de stations météorologiques : un lien fort a pu être mis en évidence entre les températures et la composition des vins. Les températures fraîches sont favorables à l’accumulation de la couleur tandis que les températures chaudes contribuent à l’alcool et à la perception de rondeur. Les précipitations quant à elles semblent expliquer les variations entre millésime (effet millésime). Enfin, il est apparu que cet effet du sol et du climat peut être gommé ou transcendé par la forte influence des pratiques des vignerons. Elles interviennent, notamment la fertilisation, sur la qualité des produits en particulier l’acidité et le potentiel polyphénolique.

The “Institut Rhodanien” has established, a vine network in the Southern part of the Rhône Valley from 1995 to 1999. Twenty four plots, planted with Vitis vinifera L. cv red Grenache have been chosen in order to study the influence of the “terroir” (soil, climate, vine grower) on wine quality. The plots were representative of the different geographic and geopedologic situations (soil types, different early maturing area) of the Rhône Valley. Clone, rootstock, pruning, density and age of vines were identical for each plot. Thus, only the environmental features (soil, climate) and viticultural practices varied during the survey. This work shows that:

– Environmental conditions have an important incidence on grape and wine quality, especially on organoleptic characteristics. The type of soil influences water balance in vine, which it conditions growth and plant vigour. A high plant vigour is detrimental to wine quality. Climatic parameters (temperatures and precipitation) were monitored directly on the plots as well as on meteorological stations. There is a strong correlation between temperature and wine composition. Cool temperatures are in favour of coloured wines, while higher temperatures help to produce alcoholic and full wines. Variations on rainfall are responsible for vintage variability.
– Finally this work also shows that sol and climate, effects are easily modified or covered by the “vine grower’s effect” (fertilisation, training management…). Viticultural practices have a strong influence on acidity and colour potential of the wines.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

C. SIPP (1), O. JACQUET (2), C. RIOU (3)

(1) Syndicat des Vignerons Réunis des Côtes du Rhône, Institut Rhodanien , 2260, route du Grès, 84100 Orange (France)
(2) Chambre d’Agriculture du Vaucluse, Institut Rhodanien, 2260, route du Grès, 84100 Orange (France)
(3) Inter Rhône, Institut Rhodanien, 2260, route du Grès, 84100 Orange (France)

Contact the author

Keywords

sol, qualité des vins, climat, Grenache, terroir soil, wine quality, climate, red Grenache, “terroir”

Tags

IVES Conference Series | Terroir 2002

Citation

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