Phenolic content in wine the ellagic and gallic acid found in the wood. In the vineyards, there is also a growing distinction being made between "ripe" and "unripe" tannins present in the grape. This "physiological ripeness", which is roughly determined by tasting the grapes off the vines, is being used along with sugar levels as a determination of when to harvest. The idea is that "riper" tannins will taste softer but still impart some of the texture components found favorable in wine. In winemaking, the amount of the time that the must spends in contact with the grape skins, stems and seeds will influence
Phenolic content in wine produce grapes with higher levels of resveratrol than warmer, drier wine regions such as California and Australia. Different grape varieties tend to have differing levels, with Muscadines and the Pinot family having high levels while the Cabernet family has lower levels of resveratrol. In the late 20th century interest in the possible health benefits of resveratrol in wine was spurred by discussion of the French paradox involving the health of wine drinkers in France. Piceatannol is also present in grape from where it can be extracted and found in red wine. Vanillin is a phenolic aldehyde most commonly associated with