Wine · Terminology

Tannin

The drying, grippy compounds from grape skins, seeds, stems and oak that give red wine its structure.

Tannin is the group of polyphenolic compounds that make a red wine feel drying, grippy and textured — the sensation of a tea bag left too long in the cup, or of a tiny leather jacket over the tongue. It is a tactile thing rather than a taste: tannin binds to the proteins in your saliva, which is why the mouth feels stripped rather than sour or bitter.

Most tannin comes from the grape skins, seeds and stems, extracted during maceration; some comes from oak during maturation. White wines have very little because the juice is normally pressed off the skins before fermentation.

In practice

  • More skin contact, warmer ferments and harder pressing all mean more tannin.
  • Ripeness changes the character: ripe tannins feel round and velvety; unripe ones feel green, hard and bitter.
  • Tannin polymerises with age — the molecules link into longer chains, drop out as sediment, and the wine softens.
  • Thick-skinned varieties give the most: Cabernet Sauvignon, Nebbiolo, Tannat, Syrah.

Where you'll meet it

  • Any structured red — most obviously Bordeaux and Barolo.
  • Orange and skin-contact whites, where white grapes are fermented on their skins.
  • In service: tannic young reds are the ones that benefit from decanting.

Judging tannin in a glass

Assess quantity and quality separately — exam mark schemes reward both.

Low Medium High
Feel Barely any grip Grip on the gums, fades Mouth-coating, drying, lingers
Typical wine Gamay, Pinot Noir Merlot, Sangiovese Nebbiolo, Cabernet Sauvignon, Tannat

Then ask what kind: fine-grained and silky (ripe fruit, gentle extraction), chalky (a common Sangiovese and Nebbiolo signature), or green and rasping (underripe fruit or stem inclusion).

Why it matters

  • Ageing. With acidity, tannin is the wine's skeleton; high-tannin reds are the ones built to be cellared.
  • Food. Tannin binds to protein and fat, which is why a tannic red and a rare steak flatter each other — and why tannin and chilli heat do not.
  • Winemaking. Everything from destemming to pressing pressure to cap management is a decision about how much tannin ends up in the bottle.

Browse the full wine terminology A–Z →