Tannins are the phenolic compounds* in wines that leave a bitter, astringent, dry, and puckery feeling in the mouth.

Grape tannin comes from the skins, seeds, and stems of a grape. This is why red wines tend to have higher tannins than white wines, as red wine has extended contact with the grape skins, giving the tannins time to dissolve.

*phenolic compounds — natural compounds present in grape skins and seeds

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