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IVES 9 IVES Conference Series 9 Successive surveys to define practices and decision process of winegrowers to produce “Vins de Pays Charentais” in the Cognac firewater vineyard area

Successive surveys to define practices and decision process of winegrowers to produce “Vins de Pays Charentais” in the Cognac firewater vineyard area

Abstract

[English version below]

Le vin est un des produits finis que l’on obtient à partir de raisins. La vigne réagit à de nombreux facteurs environnementaux et son comportement est directement influencé par les pratiques culturales. L’expression du terroir dans les vins résulte de ces interactions, à la fois au cours du cycle végétal et au cours de la vinification. Pour identifier les pratiques agricoles, viticoles et œnologiques des viticulteurs et pour classer leurs effets sur les vins d’Anjou l’UMT Vinitera a proposé une méthode basée sur des enquêtes successives. Cet article vise à expliquer comment la méthodologie mise au point par l’équipe de l’UMT Vinitera sur le vignoble Anjou Village Brissac (AVB) a été transférée dans le vignoble Cognaçais.
En effet, le vignoble des Charentes est une aire de production d’eau-de-vie de Cognac très étendue : près de 80 000 hectares de vignes parmi lesquels seules quelques parcelles (environ 2000 hectares) sont destinées à la production de vin sous appellation Vin de Pays Charentais (VPC). Les itinéraires techniques spécifiquement pratiqués sur le vignoble VPC n’avaient jamais été étudiés jusqu’à présent et demeuraient méconnus. La première partie du travail a consisté à échantillonner environ 50 des 800 producteurs de VPC sur le vignoble Cognaçais. Ensuite un questionnaire a été élaboré pour recenser les différentes pratiques employées en viticulture et en œnologie ainsi que les motivations des agriculteurs pour produire du vin dans la région. Les résultats de cette première enquête démontrent que la structure d’exploitation et le traitement de la vendange sont des critères distinguant 3 groupes de vignerons VPC, avec différents niveaux d’implication technique sur leurs vignes et leur terroir.
Une seconde enquête est ensuite réalisée et chacun des ces groupes s’est vu adresser un questionnaire spécifique. L’objectif est de distinguer les pratiques agronomiques employées d’une part pour le VPC et d’autre part pour l’eau-de-vie de Cognac. Par des séries de questions fermées successives les producteurs sont amenés à expliquer pourquoi leurs itinéraires techniques varient d’un produit à l’autre et d’un terroir à l’autre (processus dichotomique). Ainsi cette enquête nous permet de comprendre comment un vigneron structure l’arbre de décision qui définit ses pratiques agronomiques et œnologiques pour le Vin de Pays Charentais.

Wine is one of the final products made from grapes. Vine reacts to numerous environmental factors and its behavior is directly modified by winegrower actions. Terroir expression in wines ensues from those interactions during both agronomical and enological process. To identify winegrowers’ agricultural, viticultural and enological practices and to classify their effects on wines in the French region of Anjou, UMT Vinitera suggested a method based on successive surveys. This paper aims at showing how the methodology submitted by UMT Vinitera team on Anjou Village Brissac (AVB) vineyard has been transferred to the Cognac area.
Actually, the Charentes vineyard is a huge Cognac firewater production area : almost 80000 hectares of vine among which only few plots (about 2000 hectares) are set aside for growing wine, named “Vin de Pays Charentais” (VPC). Technical itineraries specifically practiced on VPC vineyard had never been studied before and were quite little-known in this region.
First part of the work consisted in sampling 50 of nearly 800 farmers who are producing VPC in the Cognac vineyard. This wine is making barely always up a smaller part of the income than the Cognac eau-de-vie. Then a questionnaire was built to register the various cultural methods used to grow vine and wine (both for Cognac firewater and VPC) and also farmer motivations to produce specifically VPC in the area. Results of this first stage of surveys show that farm structure and grape harvest treatment are criteria that distinguish 3 groups of VPC winegrowers, with different level of technical influence on their vineyards and terroir.
In a second stage of surveys, each of these groups was addressed a specific questionnaire. The objective was to segregate agronomical practices used on one hand for the VPC and on the other hand for the Cognac firewater. Afterwards, by sensible series of closed questions (dichotomous process), farmers were lead to explain why their technical itineraries change from one product to the other and from one terroir to the other. This survey so allows us to understand how a winegrower builds the decision tree which defines his specific agronomical and enological actions for the VPC.

 

DOI:

Publication date: December 3, 2021

Issue: Terroir 2010

Type: Article

Authors

BERNARD F.M. (1), WINTERHOLER R. (1) & THIOLLET-SCHOLTUS M. (2)

(1) IFV, Institut Français de la Vigne et du vin, 15, Rue Pierre Viala, 16130, Segonzac, France
(2) INRA UEVV, UMT Vinitera, 42, Rue Georges Morel, BP 60057, 49071 Beaucouzé, France

Contact the author

Keywords

Vin de Pays Charentais, Itinéraire technique, Enquêtes, Processus dichotomique
Vin de Pays Charentais, Technical itinerary, Surveys, Dichotomous process

Tags

IVES Conference Series | Terroir 2010

Citation

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