EVOLUTION OF PHENOLIC-COMPOUNDS IN RED WINEMAKING AS AFFECTED BY MUSTOXYGENATION

In a preliminary study we followed the evolution of anthocyanins and o ther phenolics during the fermentation of red Sangiovese grapes (no SO 2 added) which were treated with two different amounts of oxygen prior to fermentation. Musts to which oxygen had been added showed a consis tent decrease in red pigments, anthocyanins, hydroxycinnamyl tartaric acids and total phenolics during the skin contact compared to the not oxygenated control. After six months of storage, the oxygenated trials exhibited a lower content of tannins, catechins, and total anthocyani ns, a reduced color density and an higher percentage of polymeric pigm ent compared to the control wine. Significant sensory differences were found among wines; the most preferred wine was that obtained with lim ited oxygenation in the prefermentative phase (75 mL/kg) due to its lo w astringency and good balance.