Inhibitory effect of fungoid chitosan in the generation of aldehydes relevant to photooxidative decay in a sulphite-free white wine

Antonio Castro Marin (1, 2) , Pierre Stocker (1) , Fabio Chinnici (2) , Mathieu Cassien (1, 3) , Sophie Thétiot-Laurent (1) , Nicolas Vidal (1, 3) , Claudio Riponi (2) , Bertrand Robillard (4) , Marcel Culcasi (1) , Sylvia Pietri (1)

1 ICR - Institut de Chimie Radicalaire
2 UNIBO - Alma Mater Studiorum Università di Bologna = University of Bologna
3 YELEN
4 Institut Oenologique de Champagne

The reaction pathways were investigated by which a fungoid chitosan (CsG) may protect against photooxidative decay of model solutions and a sulphite-free white wine. Samples containing CsG were dark incubated for 2 days before exposure to fluorescent lighting for up to 21 days in the presence of wine like (+)-catechin and/or iron doses. In both systems CsG at winemaking doses significantly reduced the photoproduction of acetaldeyde and, to a better extent, glyoxylic acid, two key reactive aldehydes implicated in wine oxidative spoilage. After 21 dayx, CsG was two-fold more effective than sulfur dioxide in preventing glyoxylic acid formation and minimizing the browning of white wine. Among the antioxidant mechanisms involved in CsG protective effect, iron chelation, and hydrogen peroxide quenching were demonstrated. Besides, the previously unreported tartrate displacement from the (iron(III)-tartrate) complex was revealed as an additional inhibitory mechanism of CsG under photo-Fenton oxidation conditions.

Mots clés: Chitosan; sulphite-free white wine; photo-Fenton oxidation; aldehydes; iron chelation; antioxidant; browning; iron-tartrate complex

Domaines: Chimie analytique

Antonio Castro Marin, Pierre Stocker, Fabio Chinnici, Mathieu Cassien, Sophie Thétiot-Laurent, et al.. Inhibitory effect of fungoid chitosan in the generation of aldehydes relevant to photooxidative decay in a sulphite-free white wine. Food Chemistry, 2021, ⟨10.1016/j.foodchem.2021.129222⟩. ⟨hal-03018950⟩