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IVES 9 IVES Conference Series 9 OIV 9 OIV 2025 9 Adaptive and innovative technologies in sustainable oenology 9 Influence of maturity on grape tyrosinase activity

Influence of maturity on grape tyrosinase activity

Abstract

Enzymatic browning of grape must remains a major issue in winemaking, especially when grapes are affected by grey rot. This browning, caused mainly by the enzyme tyrosinase, leads to the formation of melanins that affects seriously the colour of white and red wines. Tyrosinase is known to oxidize ortho-diphenols into colorless ortho-diquinones that later polymerize into brown pigments. However, little recent research has been done on tyrosinase in grape must, and notably, no studies have yet investigated the effect of grape ripeness on tyrosinase activity. This study aims to fill that gap by analyzing how grape maturity influences the enzyme’s activity.

DOI:

Publication date: 22/09/2025

Issue: 46th World Congress of Vine and Wine

Type: Oral

Authors

Fernando Zamora1, Antoni Canalda1, Miriam Martínez-Guzmán1, Aitor García-Roldán1, Nadia Gregori1, Marco Bustamante1, Jordi Gombau1, José María Herás2, Nathalie Sieczkowski2, Francesca Fort1, Joan Miquel Canals1

1 Departament de Bioquímica i Biotecnologia, Facultat d’Enologia de Tarragona, Universitat Rovira i Virgili, C/Marcel.li Domingo 1, 43007 Tarragona, Spain
2 Lallemand Bio S.L. C/ Galileu 303. 1ª planta. 08028-Barcelona, Spain

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Tags

IVES Conference Series | OIV | OIV 2025

Citation

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