Wine Tip: Tannins in Wine – How it Feels

(Hottytoddy) - Two readers wrote last week to ask: “What are tannins in wine?” And “Is there such a thing as ‘soft’ tannin, since tannin is an acid?”

Although referred to as “tannic acid” by some writers, tannin is not really an acid at all, but an organic compound called a phenol. If that sounds too complicated, it is the puckery stuffer in strong tea that makes you want to put sugar or milk in it as the English do. Tannin in nuts also makes your mouth puckery if the nuts are too green. The same goes for wine.

Tannin is natural in wines; it’s present in grape skins, grape seeds, and grape stems, and even in the oak barrels, where wine is made and aged. Red wines have much more tannin than white wines because they are left on the skins longer during fermentation to obtain color. The color in red wines also comes from phenols in the skins, unlike “white” wines, which get their light yellow color from the juice rather than skin pigments.

The relation between tannin and color remains with wines as they age – old red wines get lighter as they age. And tannins separate from wines and fall to the bottom of the bottles just like the coloring agents do. In this sense tannins, like colors, do  not do not really soften, they just fall out. Lost tannin is a major reason why an old red wine often tastes better than a young one.

There is some dispute among oenologists and wine chemists, but most agree that some tannins start out softer than others. All plants have tannins, but those in persimmons are a lot more biting than those in grape skins.