Effects of hyper-oxygenation and storage of Macabeo and Airén white wines on their phenolic and volatile composition

Abstract

The effects of hyper-oxygenation and storage period of Macabeo and Airen white wines on color characteristics, phenolic, and volatile composition have been evaluated. Hyper-oxygenation treatment provoked a significant decrease in virtually all individual phenolic compounds in must, young wine, and one-year-aged wines, above all hydroxycinnamic acid derivatives, flavonols, and the new GRP derivatives compounds (derived from 2-S-glutathionyl-caftaric acid or grape reaction product). Despite this fact, the contribution of the yellow color component (b*) of white wines derived from hyper-oxygenated musts was significantly higher in comparison with untreated ones, even after 1 year of bottle storage. On the other hand, the concentration of major volatile compounds and some alcohols (namely, C6 alcohols, terpenes, and lactones) was higher in wines derived from hyper-oxygenated musts, but the hyper-oxygenation effect on volatile profile deeply depended on the grape variety. After 1 year of bottle storage, the significant differences were maintained and the content of some long-chain esters increased as a consequence of oxygen addition.