What is tannin?
KZ: Tannin is a natural preservative that is found in foods like walnuts, tea and grapes. The tannins in wine derive primarily from grape skins but can also come from the oak barrels in which certain wines are aged (which is why even some white wines, which are made without grape skins, have tannins). Tannins, when balanced with fruit, leave a tactile sensation in your mouth that is felt in the middle of your tongue. As a wine gets older, its tannins mellow and become visible in the wine as sediment. Of course, tannins are just one component of a wine’s structure; the best wines have a balance of tannins, fruit and acids.