Evolution of Phenolic Compounds in Red Winemaking as Affected by Must Oxygenation

Abstract

In a preliminary study we followed the evolution of anthocyanins and other phenolics during the fermentation of red Sangiovese grapes (no SO₂ added) which were treated with two different amounts of oxygen prior to fermentation. Musts to which oxygen had been added showed a consistent 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 anthocyanins, a reduced color density and an higher percentage of polymeric pigment compared to the control wine. Significant sensory differences were found among wines; the most preferred wine was that obtained with limited oxygenation in the prefermentative phase (75 mL/kg) due to its low astringency and good balance.