The explosion of interest comes in part from changing tastes. "We're seeing the maturation of the American palate," says Michael Whiteman, president of Joseph Baum & Michael Whiteman Co., a restaurant consultant in New York. "It's a shift from sweet, salty, and fat, which is what most Americans have been brought up on, to bitter and tart, more European." Dan Barber, chef and co-owner of Blue Hill at Stone Barns in Pocantico Hills, N.Y., livens up almost all of his dishes with a vinaigrette. It cuts fat and "gives a cleanliness and purity to food and flavors that's hard to come by without it," he says. Other chefs are dusting food with powdered vinegars to add tang. Says James Beard Award winner Rozanne Gold, best known for her 1-2-3 cookbook series: "Acidity may be the most important quality in dishes today."
A primer is in order: Vinegar is usually made from fruit or grains and aged in wooden barrels or steel vats. Its strength is measured by its percentage of acetic acid. Each batch has a starter or "mother" vinegar, a carbohydrate produced by vinegar bacteria. How the vinegar is aged, and for how long, affects its taste.
High-quality artisanal vinegars are crafted in barrels, something always noted on their labels. The aging process can take months, or, in the case of some traditionale balsamics, decades. These are made according to standards set by the Consortium of Producers of Traditional Balsamic Vinegar of Modena. Made from grapes that first have been cooked down, these vinegars are dark, syrupy, sweet—and often pricey. A 25- to 35-year-old Giuseppe Giusti is $129.99 for 100 milliliters at DiPalo's, a cheese and specialty foods store in New York. "That's why you want to taste it first," says co-owner Sal DiPalo, who keeps 10 varieties open for customers to sample. Most artisanal infused vinegars run from $8 to $15 a bottle.
Maggie Green, an editor of the 2006 edition of The Joy of Cooking, says every cook should have three basic vinegars on hand: red wine, balsamic, and rice vinegar. All are easy to find in supermarkets. Green suggests avoiding those with additives such as sugar, which often mask inferior taste.
When tasting at home, use a small plastic cup or spoon. DiPalo suggests drinking water and eating a breadstick between spoonfuls. Better, visit a gourmet store that has bottles open for customers to sample. Zingerman's in Ann Arbor, Mich., stocks 25 vinegar selections, all available for tasting.
Vinegar lovers say part of the fun is discovering a new favorite, such as the Sanchez Romate sherry vinegar preferred by Zingerman's retail sales taster Solomon James, or Minus 8, an ice wine vinegar that Patrick Feury, executive chef at the Berwyn (Pa.) restaurant Nectar, uses in an Asian-inspired tuna dish. Of course, you don't need to be a chef to find your own favorite—just willing to take a new look down the specialty foods aisle. By Roberta Bernstein