volatile acidity
Also called simply VA, volatile acidity is as much a part of wine as body temperature is in a human. A balanced amount of VA is necessary for aroma and flavor but, just as a fever indicates a problem in man, excess volatile acidity in wine signals trouble. VA can be caused by several acids, even though its primary source is acetic acid (see acids) and is the result of bacteriological infection through oxidation during winemaking. In quantities of less than 0.05 percent, volatile acidity doesn’t affect a wine’s quality. At higher levels, however, VA can give wine a sharp, vinegary tactile sensation, which is caused by acetic acid. In wines with excessive volatile acidity, the acetic acid is accompanied by ethyl acetate, which contributes a sweet, vinegary smell. Extreme volatile acidity signifies a seriously flawed wine. Such a wine can be referred to as volatile. See also volatile .
The New Wine Lovers Companion, 2nd Edition, by Ron Herbst and Sharon Tyler Herbst. Copyright © (1) 2003, 1995 by Ron Herbst and Sharon Tyler Herbst. Reprinted by arrangement with Barron's Educational Series, Inc.