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IVES 9 IVES Conference Series 9 WAC 9 WAC 2022 9 4 - WAC - Posters 9 Le cuivre sur raisins et moûts: dosage et intérêts de la mesure

Le cuivre sur raisins et moûts: dosage et intérêts de la mesure

Abstract

Avec l’accroissement des surfaces viticoles conduites en Bio, la question de l’impact de la présence de résidus de cuivre (seul anti fongique autorisé dans l’UE dans ce cadre Règlementaire) sur le déroulement des fermentations et sur les qualités œnologiques et organoleptiques des vins s’est révélée de plus en plus cruciale.

Afin de compléter les travaux déjà existants et de répondre aux préoccupations des vinificateurs, nous avons travaillé sur des méthodes d’analyses rapides sur moûts. Nos recherches nous ont confirmé qu’il était possible de développer dans les laboratoires d’œnologie un dosage colorimétrique automatisable sur un analyseur séquentiel. Son application sur moût permet de produire des analyses à faible coût et dans un délai le plus souvent compatible avec la prise de décision à l’échelle d’une unité de vinification. Grace à cette évolution, nous avons pu montrer que les limitations réglementaires de cuivre au vignoble (4 kg / ha et par an) permettent de limiter les teneurs dans les moûts, que l’évaluation à la parcelle peu avant la récolte permettait d’anticiper les valeurs sur les moûts issus du pressurage direct,  que le débourbage des jus blancs ou rosés avait des effets variables sur la teneur en cuivre avant levurage, que les fermentations alcoolique et malo – lactique n’étaient en général que très peu affectées du point de vue de leurs cinétiques (sauf dans le cas de co-inoculations sur mout blanc présentant des doses initiales importantes en cuivre) et que les effets sensoriels étaient significatifs mais impliquaient des mécanismes jusqu’alors non mis en évidence. Nos travaux ouvrent ainsi des perspectives pour une meilleure compréhension des conditions les plus favorables à l’obtention de vins aromatiques et intenses.

DOI:

Publication date: June 27, 2022

Issue: WAC 2022

Type: Article

Authors

Daniel, GRANES, Florent, DOUAL, Jacques, ROUSSEAU, Céline, RAYNAL, Magali, DELERIS

Presenting author

Daniel, GRANES – Groupe ICV

Groupe ICV, Lucile, PIC | Groupe ICV | Groupe ICV, Céline, RAYNAL | Lallemand | Lallemand

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Keywords

cuivre – analyse séquentielle – fermentation alcoolique – fermentation malolactique – arômes

Tags

IVES Conference Series | WAC 2022

Citation

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