What is Tannin?
Tannin is a chemical compound that naturally occurs in certain food stuffs and are found in grape skins and pips. Practically all grape juice is clear and so to create red wine, the grapes are left with the skins for about 30 days so the juice can extract colour and flavour – this is called maceration. During this process, tannin is also extracted from the skins and pips.
Tannin gives a wine structure, acts as a natural preservative and its break down plays an important part in the maturation of wine. It has a drying effect in the mouth and high levels of tannin can cause a “fuzzy” feeling on the teeth and gums which is why thick skinned grapes with high tannin levels such as cabernet sauvignon are often blended with grapes like merlot that have softer tannins to lessen this tannic effect. Tannins are also present in wood and so oak aging (which involves putting wine into an oak barrel or cask for a period of time) will increase the tannin levels in the wine. Following time maturing in oak, a wine will then be lain down in the bottle. With age the high levels of tannin will break down and produce rich, smooth, vanilla flavours in the wine.
Because white wines do not go through the maceration process to extract colour from the skins, they generally do not contain tannins unless they have been aged in oak barrel or have had flavour added via the addition of oak chips.
Tannin produces a chemical reaction with protein transforming the dry, fuzzy feel into a silky smooth sensation, which is why wines with good tannins go so well with high protein foods such as cheese and red meats. In general, tannins tend to be more pronounced in European wines because these wines are, more often than not, intended to be accompanied with food.
