Tannin refers to a group of polyphenolic compounds that contribute bitterness and, especially, a drying or gripping sensation to wine. In red wine, tannins come mainly from grape skins, seeds and stems, and can also be extracted from oak barrels during maturation. Tannin contributes structure, texture and the potential for bottle development.
Skin contact during fermentation extracts tannins from grape skins and seeds. Whole-bunch or stem inclusion can contribute additional tannin and herbal character. Oak barrels can add their own tannins and influence the wine’s structure. The amount and character of tannin depend on grape variety, ripeness, extraction, fermentation and ageing.
Tannin is often described as soft, fine-grained, silky, firm, coarse or aggressive. It interacts with proteins in saliva and creates a drying or puckering sensation known as astringency. Tannin is not the same as acidity, bitterness or alcohol, although these elements can be perceived together.
Firm tannins can provide structure for wines that are intended to age, but tannin alone does not guarantee longevity. Fruit concentration, acidity, balance, producer, vintage and storage conditions also matter. During bottle ageing, tannins can change and some may precipitate as sediment.
Protein and fat can soften the perception of tannin, which is why structured reds often pair well with steak, lamb, game and aged hard cheeses. Very tannic wines can seem harsh with delicate fish or strongly spicy food.
Example: pair a young Cabernet Sauvignon with grilled ribeye, or serve Nebbiolo with braised beef and aged cheese.
Chef’s note: tannin is a structural component, not a measure of wine quality. Look for ripe, integrated tannins rather than simply high tannin levels.
This term is one of hundreds covered in depth across OCS courses, learning paths, and 1-on-1 coaching with Chef Eric.
