Tannins are natural phenolic compounds found in grapes and other plant materials. They are responsible for the sensation of "chew" or astringency that one can feel when drinking certain wines. Tannins are mainly found in grape skins, seeds and stems, but also in the wood of oak barrels used to age wine.
Here's how tannins affect wine:
1. Structure and Texture: Tannins provide structure and texture to the wine. They can give the wine a firm feeling in the mouth, contributing to its complexity and balance.
2. Astringency:Tannins are responsible for astringency in wine. Astringency creates a feeling of dryness in the mouth, similar to what one might feel when drinking strong tea. This is due to the ability of tannins to bind to proteins in saliva.
3. Aging:Tannins play an important role in the aging capacity of wine. Over time, tannins can polymerize, becoming less noticeable and contributing to the sweetness and complexity of aged wine.
4. Color:Tannins are also responsible for the color of wine, especially in the case of red wines. The more the skin of the grapes remains in contact with the must during vinification, the more the wine will be rich in tannins and will have an intense color.
5. Complementarity with Foods: Tannins can interact in interesting ways with foods. The tannins present in wine can soften the fat in meats, thus balancing the flavors when pairing food and wine.
It is important to note that the amount and type of tannins vary depending on the grape variety, the winemaking method and the aging in oak barrels. Tannins are a crucial element in wine tasting, contributing to its complexity and unique character.