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IVES 9 IVES Conference Series 9 Terroir characterization from cv. Merlot and Sauvignon plots follow-up within the scope of wine-production : “Vins de Pays Charentais” in the Cognac eaux-de-vie vineyard area

Terroir characterization from cv. Merlot and Sauvignon plots follow-up within the scope of wine-production : “Vins de Pays Charentais” in the Cognac eaux-de-vie vineyard area

Abstract

[English version below]

Dans les études des terroirs, il est souvent délicat d’établir des zonages et de mesurer les effets de l’environnement sur les vins. Avec plus d’un million d’hectares dans l’aire d’appellation délimitée, le terroir du célèbre vignoble de Cognac est bien connu pour ces eaux-de-vie et ainsi divisé en 6 crus.
Cette étude vise à décrire le terroir des Vins de Pays Charentais (VPC) produits dans le vignoble Cognaçais. Les principaux cépages spécifiquement destinés à la production de VPC (Merlot et Sauvignon blanc) ont été étudiés en collectant de nombreuses données sur 5 millésimes et 35 parcelles représentant la diversité agro-pédo-climatique de la région. Comme souvent dans les essais au champ les expérimentateurs ont été confrontés à de multiples facteurs croisés et de nombreux paramètres ont été suivis. A ce stade, peu de données climatiques ont été introduites et les données de dégustation n’ont pas été incluses.
Une expertise préliminaire a permis de sélectionner certaines variables, classées en 4 groupes distincts : données climatiques et pédologiques, matériel végétal, phénologie et vinification.
L’analyse statistique exploratoire a fait ressortir certaines variables influentes, par exemple l’ère géologique et le type de sol, qui distinguent des unités cohérentes d’un point de vue géographique notamment les îles de Ré et d’Oléron. Le comportement des vignes VPC est ensuite étudié sur chacune de ces unités afin de définir ces terroirs viticoles.
Les groupes de parcelles destinées à la production de vin semblent concorder pour une bonne part aux crus des eaux de vie de Cognac même si le cépage et le type de produit diffèrent. Ces résultats vont permettre de réfléchir sur différents moyens d’optimiser l’effet terroir par les pratiques des producteurs de VPC sur les différents terroirs.

Zoning and understanding the effects of the environment expressed in vine products has always been a difficult work to start off with terroir. Thus, with more than one million hectares in the delimited appellation area, the famous Cognac vineyard terroir is well-known for eaux-de-vie and divided in 6 vintages areas since the beginning of the 20th century.
This project aims at describing the terroir for wines named “Vins de Pays Charentais” (VPC) produced in the Cognac vineyard. Main cultivars specifically used to produce VPC (Merlot and Sauvignon Blanc) were studied by collecting a set of data, using 6 years and 35 plots to represent the diversity of environmental and cultural situations in the area. As often in field trials, experimenters were confronted with many crossed factors and numerous variables were measured. At this stage, only few climatic data is available. A preliminary expertise allowed to choose some of the variables sorted in 4 distinctive groups : soil and climate data, plant material, vine cycle and grapes and then wine-making process. Tasting data was not taken into account regarding as its robustness.
The statistical exploratory analysis brought out some influential variables, as for example geological era and soil type, that clearly segregate coherent geographic units, notably Ré and Oléron islands which are breaking away. From then on, to define various “wine-terroirs” these clusters should each correspond to consistent VPC grapevine behavior and wines.
Most climatic data still has to be crossed with the plots groups sorted, but the clusters of wine producing plots already appears to tally, at least partly, Cognac firewater vineyards classification even if cultivars and type of product differ. These results allow to consider various means to optimize terroir effect by VPC winegrowers’ practices on each plot, depending on its cluster.

DOI:

Publication date: December 3, 2021

Issue: Terroir 2010

Type: Article

Authors

BERNARD F.M. (1), PREYS S. (2), GIRARD M. (3) & MORNET L. (4)

(1) IFV, Institut Français de la Vigne et du vin, 15 Rue Pierre Viala, 16130, Segonzac, France
(2) Ondalys, 385 Avenue des Baronnes, 34730, Prades-Le-Lez, France
(3) Chambre d’Agriculture de Charente-Maritime, 3 Boulevard Vladimir, 17100, Saintes, France
(4) Chambre d’Agriculture de Charente, 25 Rue de Cagouillet, 16100, Cognac, France

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Keywords

Vins de Pays Charentais, Merlot, Sauvignon, Terroir viticole, Sol, Millésime
Vins de Pays Charentais, Merlot, Sauvignon, Wine-terroir, Soil, Vintage

Tags

IVES Conference Series | Terroir 2010

Citation

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