Tannins, or tannic acid, are compounds found in several foods and herbs, and in wine and tea as well. They are astringents and are responsible for the puckering feeling you get when you bite into certain fruits or drink tea.
Tea and Tannins
Tea, both black and herbal, is a source of tannins. The amount of tannins in the particular tea will vary based on the amount in the leaves or bark from which the tea is brewed. Black tea contains more tannins than green tea, because of the longer fermentation time for black tea leaves.
Tannins in Wine
Tannins exist in grapes and thus end up in wine, where they are actually key in creating the particular flavor of the wine.
Chocolate Tannin Content
Chocolate is another source of tannins, making it one of the healthier sweets around. Dark chocolate contains more tannins than milk chocolate or white chocolate, according to a report from the American Culinary Federation.
Fruit and Tannins
Several types of fruits, including peaches, blackberries and cranberries, contain tannins. One of the main differences between two types of persimmon, the Hachiya and the Fuyu, is that the Hachiya is intensely bitter when unripe because of tannins.
Herbs and Tannins
Numerous herbs, both culinary and medicinal, contain tannins. These range from cinnamon and thyme to black cohosh and feverfew. If a tea is made from tannin-containing herbals, the tannins will be in that tea as well. A study in the August 2003 issue of "Life Sciences" reports that tannins found in traditional Chinese herbs have blood-pressure lowering effects.