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IVES 9 IVES Conference Series 9 Flanan-3-ol compositional changes in red grape berries (Vitis vinifera L. cv Cabernet franc) from two terroirs of the Loire Valley (France)

Flanan-3-ol compositional changes in red grape berries (Vitis vinifera L. cv Cabernet franc) from two terroirs of the Loire Valley (France)

Abstract

[English version below]

La quantité et la qualité des flavonoïdes sont des éléments importants de la qualité de la baie. En particulier, les tannins contribuent de manière essentielle aux propriétés spécifiques des vins rouges telles que la couleur, l’astringence et l’amertume. Cependant, leur synthèse et leurs propriétés sont encore mal connues. Ainsi, la compréhension des relations qui existent entre, d’une part, le milieu et d’autre part la mise en place de ce pool tannique jusqu’à la vendange est insuffisante. La composition en tannins des pellicules est suivie depuis le milieu de la phase de croissance herbacée (30 jours après le début floraison) et jusqu’à une maturité normale, sur deux parcelles. L’étude considère un stade donné de développement et non pas la valeur moyenne des paramètres à la parcelle. Ainsi, l’apport d’une relation plus fonctionnelle entre composition et stade physiologique du raisin constitue un levier puissant d’interprétation. La composition en flavan-3-ols et en proanthocyanidines des pellicules est déterminée par HPLC-phase inverse et par histochimie. Le couplage de ces deux techniques permet d’associer des informations quantitatives et spatiales. Cette approche originale permet de mettre en évidence l’importance de la période pré-maturation, en relation avec l’avancement de la maturation mais également d’autres facteurs, comme le nombre de pépins. Qualitativement et quantitativement, les teneurs évoluent peu après véraison. Il est suggéré que le pool tannique est acquis avant véraison. D’autre part, il est montré une relation entre le nombre de pépins des baies et leur qualité.

The quantity and the quality of flavonoïds are important parts of the global quality of the grape berries. Especially, the tannins are responsible of some majors flavour properties of the red wines including colour, bitterness and astringency. Nevertheless, their synthesis and properties are still misunderstood. Thus, the comprehension of the relations between environment and setting of this tannic pool, up to the harvest of the grapes, is not sufficient. The tannin composition was monitored since the middle of the first growth period (30 days after the onset of flowering) to the average maturity, for two plots. The study the stage of the berries, and not the average value of the parameters. Thus, the contribution of a more functional relation between composition and physiological stage of the grape constitutes a powerful lever for interpretation. The composition in flavan-3-ols and in proanthocyanidins of skins were determined by HPLC reversed phase and by histochemistry. The linking of these two analytical techniques allowed the association of quantitative and spatial data. This original approach pointed out the importance of the period previous maturation in relation with the stage of maturation but also others factors, such as the number of seeds. There was little evolution of the tannins after veraison. It is suggested that the tannic pool is set before veraison. More, a relation between the number of seeds and the quality of the berries was shown.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

Y. Cadot (1), M.T. Miňana (1), R. Champenois (1), M. Chevalier (2) and G. Barbeau (1)

(1) Unité Vigne et Vin, Institut National de la Recherche Agronomique, Centre de Recherches d’Angers, 42 rue Georges Morel, 49071 Beaucouzé Cedex, France
(2) Unité Mixte de Recherche Génétique et Horticulture (GenHort), Institut National de la Recherche Agronomique, Centre de Recherches d’Angers, 42 rue Georges Morel, 49071 Beaucouzé Cedex, France

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Keywords

Tannins, maturation, Vitis vinifera var. cabernet franc, skin, seed, histochemistry

Tags

IVES Conference Series | Terroir 2004

Citation

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