Acids occur naturally in grapes. Additional acids are produced when wine grapes are fermented. Acids may also be added during fermentation, to help balance the character and flavors of a wine.
There are three primary acids associated with wines:
1. Citric acid
2. Malic acid
3. Tartaric acid
Acids are vital to wines, as they can directly affect the flavor, balance, tartness, and ‘liveliness’ of a wine.
Overall acidity varies with the type of grapes. Sweet wines typically contain more acid than dry wines.