New Insights into Intrinsic and Extrinsic Factors Triggering Premature Aging in White Wines

Two grape antioxidants, ascorbic acid and glutathione, and a flavan-3-ol, catechin, were analyzed and related to the production or depletion of volatile compounds (phenylacetaldehyde, methional, and sotolon) that act as markers of premature aging in dry white wines. This research assessed the impact of adding ascorbic acid (AA, 80 mg/L) and glutathione (GSH, 10 mg/L) to a Sauvignon Blanc wine sealed with two closures with different permeability to oxygen on wine flavor development over 10 years' bottle storage. A decrease in AA was correlated with the closure's oxygen permeability, while GSH depletion (90 % in 12 months) was associated with the dissolved oxygen content at bottling. Sensory analysis revealed significant differences in the development of wine oxidation flavors, correlated with the closure, as well as AA and GSH content. Wines spiked with AA and GSH at bottling were preferred by panelists to controls, without GSH. The sensory data were in complete agreement with analytical results, showing that these wines had the lowest sotolon content. We also demonstrated that, on the basis of analyzing the oxidation markers (sotolon, methional, and phenylacetaldehyde), high catechin levels in white wines contributed to their formation in a temperature-dependent manner.