🍷 Tannins

Tannins are substances found in the skins, seeds and stems of grapes, and in oak. They give wine a drying, grippy feel: the mouth feels dry, as after strong tea. They are an important part of the structure of red wines.

Tannins pass into wine during maceration, when the juice stays in contact with the skins. The longer the contact, the more tannin. Seeds give harsher, bitter tannins, so winemakers try not to crush them. Oak tannins are added during ageing in barrel. Tannins belong to a large group of compounds called polyphenols.

Tannins help wine keep for a long time, which is why firm red wines can age for years. With time they soften. White wines usually have little tannin unless they had skin contact. Knowing about tannins helps explain why one wine feels soft and another astringent.