Quantification of the production of hydrogen peroxide H2O2 during accelerated wine oxidation.

Abstract Understanding how wines react towards oxidation is of primary importance. Here, a novel approach was developed based on the quantitative determination of the key intermediate H 2 O 2 produced during accelerated oxidation by ambient oxygen. The assay makes use of the conversion of the non-fluorescent Amplex Red substrate into a fluorescent product in presence of H 2 O 2 . The total production of H 2 O 2 during 30 min was quantified with low within-day and between-day variabilities. Polymerized pigments, but not total polyphenols, played a major role in the determination of H 2 O 2 levels, which were lower in white wines than red wines. H 2 O 2 amounts also increased with temperature and the addition of metal ions, but did not depend on the concentration of many other wine constituents such as SO 2 . H 2 O 2 levels did not correlate with anti-oxidant properties. We believe that this novel methodology might be generically used to decipher the oxidation mechanisms in wines and food products.