Quantifying Cumulative Wine Oxidation via Acetaldehyde Condensation Reaction Products

In this project, we measured the extent that acetaldehyde reacted with several wine components, including water, ethanol, glycerol, catechin and glutathione. We also measured how fast those reactions were in the case of glycerol and catechin. These results addressed objectives 1 and 2 below. However, objective 3 was not covered. The importance of these experiments was that we now understand the fate of acetaldehyde as it is formed in wine during fermentation and later formed by oxidation. This data shows that a good fraction of the acetaldehyde is actually in bound forms with the substances studied above, but also including to SO2. This information shows that an analysis of acetaldehyde must take all these different forms into account, as well as the rate of formation of the various products. Most importantly, this data shows that some of the acetaldehyde products we thought were irreversible are in fact very reversible and that the ultimate fate of acetaldehyde will be found in different products.