The role of polyphenols in oxygen consumption and in the accumulation of acetaldehyde and Strecker aldehydes during wine oxidation.

This study explores the role of polyphenols in preventing oxidative deterioration of wine aroma. Wine models containing polyphenols extracted from grapes were fortified with delphinidin-3G (DELF) or catechin (CAT), and oxidized. DELF increased oxygen consumption rates (OCRs) and reduced the Strecker aldehydes (SAs) formation, while CAT decreased OCRs and increased SAs. Further oxidation of models with individual polyphenols: coumaric acid (COU), caffeic acid (CAF), CAT, epigallocatechin (EPIG), malvidin-3G (MV), DELF, quercetin (QUER), and myricetin (MYR) revealed that most polyphenols, except anthocyanins, slowed initial OCRs. Anthocyanins and trihydroxylated polyphenols consumed all oxygen. DELF arises as the ideal sacrificial antioxidant, consuming O quickly and quantitatively, avoiding Fenton reaction and SAs accumulation. MV was similar but caused high SAs levels. EPIG and MYR prevented Fenton reaction but induced moderate SAs accumulation. COU hardly consumed O, but prevented Fenton reaction and did not induce SAs. These findings could help enhance wine quality and stability.