Influence de l'aération et du sulfitage sur l'évolution de la matière colorante des vins rouges au cours de la phase d'élevage

Abstract

Modifications of red wines colouring material during aging, in barrels or in vats, needs the presence of oxygen to induce a production of traces of acetaldehyde from joined oxidation between alcohol and phenolic compounds. Acetaldehyde makes possible a polymerization of anthocyanins ; other phenolics take place in this reaction. As consequence, colour is increased and stabilized in spite of a decrease of anthocyanin level. An excess of sulphur dioxide rnakes these essential reactions lower.