Enoforum 2021
IVES 9 IVES Conference Series 9 Enoforum Web 9 Enoforum Web Conference 2021 9 Freeze-thaw treatment to enhance phenolic ripening and tannin oxidation of seeds

Freeze-thaw treatment to enhance phenolic ripening and tannin oxidation of seeds

Abstract

Phenolic ripening represents a major interest for quality wine producers. Nevertheless, climatic or genotypical limitations can often prevent optimal maturation process. During winemaking seeds can be easily separated and technologically processed to improve their quality. Relying on the key role of oxidation for phenolic ripening, a freeze-thaw treatment was proposed to improve the fruit quality for potential use in challenging growing conditions. The experiment was carried on in two distinctive viticultural areas, Michigan and Italy. Five cultivars (Cabernet franc, Cabernet-Sauvignon, Merlot, Pinot noir and Chambourcin) and six cultivars (Cabernet-Sauvignon, Sangiovese, Syrah, Croatina, Barbera and Nebbiolo) were used in Michigan and Italy, respectively. Samples were collected at different phenological stages, to describe the natural ripening process and grape seeds were characterized before and after a freeze-thaw treatment. Colorimetric and spectrophotometric data highlighted similarities among natural and artificial seed ripening promising future applications for the wine industries.

DOI:

Publication date: April 23, 2021

Issue: Enoforum 2021

Type: Article

Authors

RUSTIONI Laura1*, COLA Gabriele2, VANDERWEIDE Josh3, MURAD Patrick3, FAILLA Osvaldo2, SABBATINI Paolo3

1 DiSTeBA – Università del Salento
2 DISAA – Universita’ Degli Studi di Milano
3 Department of Horticulture, Plant & Soil Sciences Building, Michigan State University

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Enoforum 2021 | IVES Conference Series

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