tannin

It is an astringent and antioxidant substance that exists in high concentration in grape skin and seeds.

Tannins are responsible for the ‘dryness’ flavour and astringency of some wines, but they are also very important in achieving a good structure, velvety body and complexity.

A good aging, in a red wine, is achieved with tannins, which round over time in oak barrels (with constant microoxygenation) and in the bottle.