Modulation of colour extraction in red wines by a combination of fermentation parameters: a multi-variety comparative study

Résumé fourni par la source

ABSTRACT: (250 mots) Colour is a key indicator of perceived quality and consumer acceptance of red wines. Anthocyanins, the principal pigments responsible for red wine colour, are selectively extracted during skin maceration, which occurs simultaneously with alcoholic fermentation in red winemaking and constitutes a heterogeneous multiphase process. This study aimed to evaluate whether the modulation of fermentation parameters influences the extraction of colouring compounds into the liquid phase and to determine the consistency of these effects across three interspecific hybrids and three Vitis vinifera . The experimental approach combined comparisons of maceration duration with a Doehlert experimental design investigating the effects of three factors: temperature, nitrogen supplementation, and addition of pectolytic enzymes. Overall, colour was not significantly affected by any of the tested parameters in Artaban, Prior (ΔE=0.33 and 0.41, respectively for maceration of 8 and 14 days), both hybrid varieties. In contrast, for one Bouquet variety G14 and Vitis vinifera , (Carignan, Syrah, Pinotage), both maceration time and temperature exerted a consistently positive effect on colour extraction across all varieties. The impact of pectolytic enzyme addition was highly dependent on must characteristics. Finally, nitrogen supplementation showed no effect on colour due to the limited supplementation (in the present work) and the same yeast used. These results indicate that colour extraction in red winemaking, occurring within a heterogeneous system, cannot be optimised using a universal, “one-size-fits-all” approach. Further investigation into interactions between grape cell wall polysaccharides and colouring compounds is required to better explain the observed variability in extraction.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.