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IVES 9 IVES Conference Series 9 Aptitude du cépage Chenin à l’élaboration de vins liquoreux en relation avec certaines unités terroirs de base de A.O.C. Coteaux du Layon

Aptitude du cépage Chenin à l’élaboration de vins liquoreux en relation avec certaines unités terroirs de base de A.O.C. Coteaux du Layon

Abstract

Le cépage Chenin constitue la base des A.O.C. de vins blancs en Moyenne Vallée de la Loire, région au contact du Massif Armoricain et des premières formations sédimentaires de l’auréole Ouest du Bassin Parisien. Si on le trouve dans le monde entier (Californie, Israël, Afrique du Sud), c’est bien dans cette région qu’il affirme le mieux son identité. C’est un des cépages les plus intéressants par la variété et la complexité des vins qu’il peut produire. Il peut donner des vins très secs ou très doux, tranquilles ou pétillants, frais dans leur jeunesse et sublimes au vieillissement, exprimant tout autant les caractéristiques de chaque millésime que celles du terroir. Le Chenin est un témoin fidèle de son environnement géographique, géologique, pédologique et climatique ; il est le faire-valoir du terroir. Il a de fortes aptitudes à la production de vins liquoreux conditionnés par des raisins surmûris souvent botrytisés dans l’A.O.C. Coteaux du Layon. La richesse et la noblesse des vins issus interpellent bon nombre de connaisseurs. Les vignerons de cette zone de production veulent préserver l’identité de ces vins conformément aux lois de la nature et dans le respect des traditions (Cellier, 1996). C’est dans ce sens qu’un programme de recherche/développement a été mis en place depuis quelques années, visant à caractériser les Unités Terroir de Base qui composent la zone de production, selon une méthodologie de caractérisation intégrée (Morlat, 1989, 1996) développée par l’Unité de Recherches Vigne et Vin du Centre INRA d’Angers et à la cartographier (Bolo et al., 1996). L’Appellation d’Origine Contrôlée Coteaux du Layon présente une grande diversité de terroirs parmi lesquels différentes variantes d’altération sur diverses catégories de schistes sont très représentées. Les indices bioclimatiques viticoles classent la région en limite septentrionale de la culture de la vigne. De ce fait, le potentiel des vendanges et des vins est influencé par le millésime. Les caractéristiques climatiques en interaction avec le terroir conditionnent, d’une part la stratégie que doit adapter le viticulteur pour une récolte réalisée par tries successives, et qui s’échelonne parfois sur plus d’un mois. D’autre part, le type de surmaturité en dépend, favorisant soit le développement de la pourriture noble, soit la concentration sur souche. C’est dans ce contexte qu’un réseau de parcelles expérimentales de Chenin a été mis en place sur certaines Unités Terroir de Base du vignoble. De ce fait, et dans ces conditions, l’étude vise à mettre en évidence les aptitudes de ce cépage à la production de vins liquoreux dans l’A.O.C. Coteaux du Layon.

DOI:

Publication date: March 25, 2022

Issue: Terroir 1996

Type : Poster

Authors

C. ASSELIN (1), R. MORLAT (1), P. CELLIER (2), MARIE-HELENE BOUVET (1), A. JACQUET (1), M. COSNEAU (1)

(1) INRA – UVV Centre de Recherches Angers – 42, rue Georges Morel, 49071 Beaucouzé
(2) INAO Angers – Hôtel des vins La Godeline, 73, rue plantagenêt, 49000 Angers 

Tags

IVES Conference Series | Terroir 1996

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