What Are Tannins in Wine?

Tannins are natural compounds from grape skins, seeds and stems — and from oak barrels — that make your mouth feel dry and grippy. They are the reason a big red leaves your gums feeling slightly furry, and the reason strong black tea does exactly the same thing.

Tannin is one of the handful of words that unlocks wine, because it describes a texture rather than a flavour. Once you can feel it, you can describe almost any red wine. Here is what tannins are, where they come from, and how to spot them in your glass tonight.

What tannins feel like (not taste like)

The first thing to know is that tannin is not a flavour. It is a sensation — specifically astringency, the drying, puckering, slightly rough feeling across your tongue, gums and the insides of your cheeks.

You already know it from outside wine. Stewed black tea left with the bag in too long. The skin of a walnut. Very dark chocolate. An unripe banana. All of these grip and dry the mouth in the same way, and all of them contain tannins.

Here is a test you can do tonight with a red wine: take a sip, swallow, then wait ten seconds and run your tongue over your front teeth and gums. If they feel dry, rough or slightly sticky rather than slippery, that is tannin. A high-tannin wine makes you want to take another sip just to restore the moisture — which, incidentally, is part of why tannic reds work so well with rich food.

Where tannins come from

Tannins are a family of compounds called polyphenols, and in wine they arrive from two places.

The grape itself — skins, seeds and sometimes stems. This is the main source, and it explains the single biggest pattern in wine: red wines are fermented with their skins, which is what gives them both their colour and their tannin. Most white wines are pressed off their skins before fermenting, so they have very little tannin at all.

That is also why orange wine tastes so unusual. It is made from white grapes fermented on their skins like a red, so it picks up genuine tannic grip — a white wine with a red wine's texture.

The barrel — oak contains its own tannins, and a wine aged in new oak barrels absorbs some of them, along with flavours like vanilla, toast and baking spice. This is why a heavily oaked wine can feel firmer and more structured than the grape alone would suggest.

Why tannins matter

Tannin does three useful jobs, which is why winemakers pay so much attention to it.

• Structure. Tannin gives a wine a frame to hang its fruit on. Without it, a big red would taste flabby and sweet-ish rather than serious.
• Ageing. Tannins act as a preservative and change over time. In a young wine they can feel harsh and separate; over years they gradually link up into larger molecules and the texture softens into something silky. This is a real part of why some wines genuinely improve with age — and why a famously tannic wine like Barolo is often described as needing time.
• Food. Tannin binds to protein and fat, which is why a tannic red and a fatty steak flatter each other. The food softens the grip; the wine cuts through the richness.

Which wines have the most tannin

Tannin levels vary enormously by grape. As a rough map:

If tannin is not for you, that is a completely legitimate preference and it points you straight at light reds, whites and rosé. Our guide to the types of wine maps out where each family sits.

Tannin, dryness and bitterness are three different things

These three get muddled constantly, and separating them is one of the fastest upgrades to your wine vocabulary.

Tannin is a texture — the drying grip. Dryness is the absence of sugar, which is a matter of taste rather than feel; almost all red wine is dry whether or not it is tannic, as our wine sweetness chart explains. Bitterness is a taste, like coffee or grapefruit pith, and while very tannic wines can seem bitter, plenty of grippy wines are not bitter at all.

A wine can be tannic and fruity. It can be dry and completely soft. Being able to say “I like dry reds but not very tannic ones” is a genuinely precise description — and it is exactly the kind of sentence that gets you a great recommendation when ordering wine at a restaurant.

How to soften tannins in a glass

If a red feels too grippy right now, three things genuinely help.

• Eat something with it. Protein and fat are the fastest fix — cheese, steak, a handful of nuts. The effect is immediate and dramatic.
• Give it air. Decanting or simply swirling in a big glass for twenty minutes lets a tight young red open and soften.
• Check the temperature. Serving a red too warm exaggerates alcohol and makes tannin feel harsher; too cold makes it feel tighter and more astringent. Our serving temperature chart gives the right window for each style.

And the simplest option of all: choose a lower-tannin wine next time. Noticing that you prefer silky reds to grippy ones is not a gap in your knowledge — it is the knowledge.