SO2 reaction with electrophilic species present in wine, including in particular carbonyl compounds, is responsible for the reduction of its protective effect during wine aging. In the present study, direct 1H NMR profiling was used to monitor the reactivity of SO2 with acetaldehyde under wine-like oxidation conditions. The dissociation of acetaldehyde bound SO2 was evidenced suggesting that released free SO2 can further act as an antioxidant. EPR and DPPH assays showed an increasing antioxidant capacity of wine with the increase in the concentration of acetaldehyde sulfonate. The presence of acetaldehyde sulfonate in wines was correlated with the overall antioxidant activity of wines. The first direct evidence of acetaldehyde bound SO2 dissociation provides a completely new representation of the long-term protection efficiency of SO2 during bottle aging.
Presenting author: Sofia Tachtalidou – UMR PAM Université de Bourgogne/Agro Sup Dijon, Institut Universitaire de la Vigne et du Vin, Jules Guyot, Dijon, France
Additionnal authors: Nicolas Sok | UMR PAM Université de Bourgogne/Agro Sup Dijon, France, Franck Denat | Institut de Chimie Moléculaire de l’Université de Bourgogne, UMR 6302, CNRS, Université Bourgogne Franche-Comté, 21078 Dijon, France, Laurence Noret | UMR PAM Université de Bourgogne/Agro Sup Dijon, Institut Universitaire de la Vigne et du Vin, Jules Guyot, Dijon, France, Philippe Schmit-Kopplin | Analytical BioGeoChemistry Research Unit, Helmholtz Zentrum München, and Technical University of Munich, Germany, Maria Nikolantonaki | UMR PAM Université de Bourgogne/Agro Sup Dijon, Institut Universitaire de la Vigne et du Vin, Jules Guyot, Dijon, France, Régis D. Gougeon | UMR PAM Université de Bourgogne/Agro Sup Dijon, Institut Universitaire de la Vigne et du Vin, Jules Guyot, Dijon, France
Email: sofia_tachtalidou@yahoo.fr
Keywords: antioxidant activity-white wine-oxidation-chardonnay-aldehydes