Pucker up for tannins

What do tea and wine have in common?
More than you might think. Both contain tannins, which also occur naturally in the bark of many plants and trees, as well as in coffee, walnuts and more. Tannins are largely responsible for the flavor of red wine. They also help preserve wine, but too much tannin can be too much of a good thing. Wine that has too much tannin tastes bitter enough to cause your mouth to pucker.

Although tannins come from grape seeds and stems (also from the casks in which wine is stored), the main source is the skin of the grape. That's why red wines have much higher tannin content than white wines. It's the skin, after all, and not the color of the grape that determines the color of wine.

The juice of all grapes, with rare exception, is colorless. When making white wine, which is often made from red grapes, the skins are removed early in the process. When making red wine, the skins are left on. They dye the wine red.

The type of grape also affects the amount of tannins in the wine. For example, cabernet sauvignon grapes have more tannin than pinot noir grapes.

Tannins are especially desirable in wines that are meant to age. Because of tannin, red wines can be aged far longer that whites. Tannins mellow with age and, over time, add to the complexity of wine. But for wines that are to be consumed without aging, too much tannin can be harsh.

If a wine has high tannin content, nibbling on cheese can balance the taste, which is why wine and cheese go together so nicely. For the same reason, tea drinkers add milk to their tea. You might think twice about adding milk to your wine, but, believe it or not, wine makers sometimes cut the bitterness of tannins by adding malolactic acid, which is a milk derivative.

In addition to adding to the flavor and helping to preserve wine, tannin is used to tan animal skins to make leather, to manufacture ink and to treat burns. All in all, tannins are worth toasting.

Madeleine Ahlquist is co-owner of One Eleven Chop House and The Sole Proprietor in Worcester, both of which are frequent winners of Wine Spectator's "Award of Excellence." Comments? E-mail editorial@worcestermag.com.