What Are Tannins in Wine?

Quick answer: what are tannins?

Tannins are a group of naturally occurring phenolic compounds. In grapes, they are found mainly in the skins and seeds, with stems also contributing when they are included during winemaking. Oak can add another source of tannin as wine matures in barrels or with other oak products.

When you drink a tannic wine, you may notice that your gums and the inside of your cheeks feel dry, grippy or slightly rough. This sensation is called astringency. It is often compared with the feeling left by strong black tea or the skin of an unripe fruit.

Tannin is not simply a flavour. It is mainly experienced as a mouthfeel or texture. A wine can also taste bitter, but bitterness and astringency are different sensations.

Red wines usually contain more noticeable tannin because their juice commonly ferments with grape skins, seeds and sometimes stems. White and rosé wines generally have less extracted grape tannin, but they are not automatically tannin-free.

Where does tannin come from?

Grape skins

Grape skins contain tannins and other phenolic compounds. During red-wine production, juice remains in contact with the skins during fermentation and maceration—the period when juice and grape solids interact. This contact can extract tannin as well as colour and other compounds.

Colour and tannin often develop together, but a deeply coloured wine is not necessarily more tannic.

Grape seeds

Grape seeds are another important source of tannin. Seed tannin can contribute bitterness or a more angular, drying sensation, although its effect depends on the grape, its ripeness, the winemaking and the rest of the wine. Seed tannin is not automatically harsh or undesirable.

Stems and stalks

Stems can contribute tannin when they are included during fermentation, as in some whole-bunch styles. The result depends on factors such as stem ripeness, the proportion used and how the wine is made.

Oak

Oak barrels and other oak products can contribute tannins, along with flavours and aromas such as vanilla, toast, spice or cedar. Oak-derived tannin is not exactly the same as grape-derived tannin, but both can influence a wine’s structure and texture.

Why do red wines usually have more tannin?

In many red wines, fermentation takes place with grape skins and other solids still present. This gives the juice more opportunity to extract phenolic compounds, including tannins.

The result is influenced by much more than contact time. Grape ripeness, fermentation conditions, temperature, pressing, alcohol development, seed and skin condition, stem inclusion and other winemaking decisions all matter.

White wine is commonly pressed and separated from skins and seeds earlier, so it generally has less noticeable grape tannin. Rosé usually has shorter skin contact than red wine, but its tannin level can vary. A rosé made with extended skin contact may feel more phenolic or grippy than a pale, briefly macerated style.

What does tannin feel like?

Try focusing on your gums and the inside of your cheeks after swallowing or spitting. Tannin may feel:

• drying;
• gripping;
• firm;
• rough;
• chalky or powdery;
• puckering;
• less smooth or lubricated.

The sensation may build for a few seconds after the sip. Tannin can feel silky and fine in one wine, or coarse and aggressive in another. These are descriptions of texture, not automatic judgements about quality.

Tannin versus bitterness

Astringency is the drying or gripping mouthfeel associated with tannin. Bitterness is a taste sensation. Tannin can contribute to bitterness in some circumstances, but tannin is not the same thing as bitterness.

Tannin versus dryness

A tannic wine can feel drying, but a dry wine generally means a wine with little or no perceptible sweetness. These are separate ideas.

A wine can be dry and tannic, dry and low in tannin, sweet and tannic, or sweet and low in tannin.

Tannin versus acidity

Acidity usually feels fresh, tart or mouth-watering. Tannin feels more like grip and drying texture. A wine can have both noticeable acidity and noticeable tannin; one is not the opposite of the other.

Tannin versus alcohol and body

Alcohol may feel warm or hot. Body describes the wine’s overall weight and fullness in the mouth. Tannin can contribute to structure and substance, but it is not body itself.

A light- or medium-bodied wine can still have noticeable tannin, while a full-bodied wine can have soft tannin.

What do tannins feel like in Australian wines?

Variety is a useful clue, not a guarantee.

Australian Shiraz—the common Australian label term for Syrah—can range from supple and medium-bodied to concentrated and firmly structured. Cabernet Sauvignon often provides a clear example of a wine with noticeable tannin and structure, but Australian Cabernet varies with region, vintage, ripeness and winemaking.

Pinot Noir is often less tannic in impression than Cabernet Sauvignon, but it can still have clearly perceptible tannin. Skin contact, stem inclusion, ripeness, extraction and oak all influence the result.

A grape variety or regional name cannot tell you everything about the tannin in an individual bottle. The wine’s vintage, growing conditions, winemaking and maturation also matter.

Do tannins soften with age?

Maturation can change the way tannin feels. Some wines become less aggressively astringent or seem more integrated with time, as tannins and other components undergo chemical changes.

However, tannins do not simply vanish, and ageing does not guarantee that every tannic wine will become softer or better. Tannin is one factor that can contribute to structure and ageing potential, alongside acidity, alcohol, fruit concentration, balance and storage conditions.

More tannin is not automatically a sign of higher quality.

A simple way to taste tannin

You can try this with a small sip of red wine:

1. Notice whether the wine is sweet or dry.
2. Pay attention to its acidity: does it feel fresh or mouth-watering?
3. Let the wine move naturally around your mouth.
4. Focus on your gums and inner cheeks.
5. Ask whether the wine feels smooth or drying, soft or gripping, silky or rough.
6. Separate that sensation from alcohol warmth and bitterness.
7. Compare the feeling with strong black tea if a reference helps.

You do not need to assign the wine a precise tannin level. The aim is simply to recognise the sensation.

Choosing a softer or more structured wine

Words such as soft, supple and silky often suggest a less aggressive tannin sensation. Words such as firm, structured, grippy and chewy suggest more noticeable tannin.

These descriptions are useful guides, not exact measurements. If you prefer less drying texture, ask a retailer or cellar-door host for a softer or more supple style. If you enjoy firmness and grip, ask for something more structured.

For a refresher on tasting wine, see How to taste wine. You can also explore examples through Shiraz, Pinot Noir and Cabernet Sauvignon.

Tannin FAQs

Are tannins only found in red wine?

No. Red wines usually show more noticeable tannin, but white and rosé wines can contain tannin from grape solids, skin contact, seed contact, oak or other winemaking choices.

Are tannins bitter?

Tannin can contribute bitterness, but its main beginner-facing sensation is usually astringency: drying, gripping or puckering mouthfeel.

How can I tell if a wine has tannin?

Notice whether the wine makes your gums and cheeks feel dry, rough or grippy after the sip. Strong black tea offers a useful sensory comparison.

Which Australian wines have the most tannin?

There is no reliable universal ranking. Australian Shiraz and Cabernet Sauvignon can show noticeable tannin, while Pinot Noir can also be tannic depending on the wine’s region, ripeness and winemaking.

Does more tannin mean better wine?

No. Tannin is a style and structural characteristic, not a score for quality. A wine can be enjoyable with firm tannin, soft tannin or very little noticeable tannin.