PRETTY MUCH EVERYONE

has one tequila story that they'd like to forget.

But tequila can be more than just the shot of choice for rowdy frat boys. Premium and super-premium tequilas which are sipped like fine scotch, not drowned in margarita mix are on the rise, says Jerald O'Kennard, editor in chief of The Beverage Testing Institute, a wine, beer and spirits review guide. More than 30 new brands of premium tequila have hit the U.S. market this year alone. And sales are booming. In 2006, tequila sales increased 12.5%, according to AC Nielsen Enhanced Liquor Track, a market research group. "It's a cultural shift," he says. "Consumers are very interested in premium and super-premium liquors. They're drinking more and drinking better."

What Is Tequila?

For the uninitiated, tequila is a type of mezcal a liquor that has been distilled from the juices of the more than 200 varieties of agave plant. "All tequilas are mezcal, but not all mezcal meets the rigid standards to be called tequila," explains Matt Carroll, a spokesman for Patr n, a tequila brand. Per regulations, the only brews that can be labeled tequila are those made solely from blue agave and distilled in the Mexican state of Jalisco. Premium tequilas are further restricted to those bottled in Jalisco, and made from and labeled as "100% Blue Agave."

In other words, the cheap stuff you down as tequila shots at your local bar is likely a blend composed of, at most, just 51% agave liquor, says Alexander P rez, editor of Tequila Aficionado magazine. The rest is sugar, water and cane- or grain-based spirits (i.e., rum or vodka). It's that extra sugar that gets you drunk faster and creates a hangover you'll never forget, he says. Premium tequila won't have that effect.

Chasing Tequila

As tequila's popularity soars, so has its prices, says O'Kennard. Expect to spend at least $25 for a quality bottle of tequila blanco, the least expensive of the four varieties. Looking for aged tequila? The cheapest extra a ejos (which means extra aged) run $250 a bottle.

But don't trust that the price on the shelf is an accurate measure of the tequila's worth, he cautions. "Because tequila is an explosive liquor category, you will find price-gouging shenanigans going on," he says. To get the best deal on a bottle of your liking, consider these nine factors before heading to the store:

Category
Quality tequila that made from 100% blue agave comes in four types: blanco (silver), reposado (rested), a ejo (aged) and extra-a ejo (extra aged). "Technically speaking, the juice is the same, the production technique is the same," says Valdemar Cantu, brand manager for Herradura. "The only difference is how long it's aged." The older the tequila, the less common it is, and the higher its price. But unlike other spirits, it doesn't follow that older tequila is better. "Connoisseurs almost universally favor blancos," says O'Kennard. "It's the most expressive of the agave."

Blancos

, the most common and least expensive category, are bottled immediately after distilling.

Reposados

are aged for between two months and one year in an oak cask.

A ejos

age for one to three years in an oak cask.

Extra a ejos

, which are aged for a minimum three years, are the least common tequilas. There are so few tequilas aged that long that the Tequila Regulatory Council just approved extra a ejo as separate category in March 2006. As a result of their relative rarity, extra a ejos are also the most expensive tequilas.

Aging
Knowing the tequila's category doesn't tell you enough about what to expect from the finished product, says Cantu. A reposado aged for two months, for example, will taste markedly different (and will be slightly cheaper) than one aged for 11 months. "The older you go in tequila, the sweeter the juice becomes; the more mellow the agave essence," he says. Look for a specific number of months and/or years on the label.

It's also worth knowing what kind of casks your tequila has been aged in. Most use Scotch whisky or bourbon casks. Expect to pay more for tequilas aged in less-common casks, such as Bordeaux.

Flavor
"It's important to taste the product before you buy," says P rez. Individual tequilas vary widely in flavor due to type, age, region, brand and distillation process. "You don't want to buy a $50 bottle of tequila and be disappointed." Look to your local liquor store for tasting seminars, or better yet, head to your nearest swanky Mexican restaurant or bar.

Eben Klemm, who put together the extensive selection of more than 100 tequilas offered at New York City's popular Dos Caminos restaurants, suggests you start your tasting with blancos, and end with a ejos:

"

Blancos

are the fieriest," Klemm says. "You get more character from the agave." Expect bold citrus (particularly lime), herbal and flowery notes. "In some of the lowland tequilas, you'll also get some minerality clay, chalk," he says. If you like vodka, a blanco will probably be more to your tastes.

Reposados

are somewhat sweeter and mellower, with hints of oak, smoke and caramel amid the still-strong citrus and flowers of the agave.

"

A ejos

, you're increasing that oak intensity," he says. The abundant smoke and vanilla impart a sweeter, smoother taste, akin to a cognac. If you're a Scotch drinker, a ejos may be more your style.

Vintage
OK, this one's a nonfactor. Because agave is harvested year-round and doesn't depend on a single season's harvest, tequila is the only spirit that doesn't have vintage bottles. Don't waste your time looking for them.

Production
"I've been to distilleries where there are donkeys pulling the wheels that crush the blue agave," says O'Kennard. "These can be very, very handmade products." The less industrial the production, the more expensive the resulting tequila.

Making the Most of Your Tequila

Forget the tequila shots. Once you've purchased a quality bottle, here's how to savor it: Storage: Tequila is hardy. Simply store upright in a cool, dark place. Serving: To maximize flavor and aromatics, serve your tequila at room temperature, says O'Kennard. "Chill clamps down on the aromatics," he says the tequila just won't smell or taste as good. Use barware that properly funnels the aromas. For blancos and reposados, that's a tequila glass, or in a pinch, a Champagne flute. (Both have similar shapes.) Serve a ejos in a brandy snifter. Mixing: Blancos are best for mixing in cocktails; a ejos and extra a ejos for sipping straight up, says Carroll. Reposados can be used in either way. Accoutrements: Try the tequila neat first, urges O'Kennard. But it's acceptable to have what bars call "training wheels" a lick of salt before a sip of tequila, chased by sucking out the juice from a wedge of lime. In Mexico, tequila is traditionally chased by a sip of sangrita, an orange- or tomato-juice base mixed with chopped chile peppers. Both options cleanse your palate, keeping each sip as interesting as the first.

Color
The wood naturally lends a golden tone to tequila; the more aged the spirit, the deeper its color. But there are exceptions: Don Eduardo a jeo, though aged two years, is still a very light gold, while AsomBroso La Rosa is a vivid pink.

Composition
Just because a tequila is labeled "100% Blue Agave" doesn't mean it's free of additives, says P rez although the best tequilas are. Check the ingredients label before you buy. Some tequilas, notably those marketed as "Gold," contain caramel to add color, as well as concentrates of sherry, prune or coconut to balance out the flavor. These extras add an artificial "perfume-y" note to the smell and taste, and should be avoided at all costs, he says.

Region

What About the Worm? "If you find a worm in 'tequila,' it's not really tequila," warns P rez. "That's a big no-no." Worms are found solely in mezcals, and only inexpensive ones at that, he says. "More than anything, it's a marketing gimmick." There's some indication that a worm in the mezcal bottle is a good indication of the brew's proof or alcohol content. Intact, it's fit to drink. Disintegrating? Let the drinker beware.

Soil, weather and other environmental factors have an impact on the flavor of the agave, and of the resulting tequila, says Carroll. It's tough to taste the difference without an experienced palate, but it's worth knowing that the tequilas with the most desirable flavors come from the highlands surrounding Guadalajara.

Brands
You don't need to be a tequila aficionado to recognize the big names in the industry among them, Patr n, Don Julio, Cuervo and Herradura. But Mexico's tequila region is home to more than 100 distilleries that produce 600-plus brands, each with its own style. "Go out and explore," says P rez. "There are a lot of very good tequilas out there that don't have that big corporate backing." Boutique tequilas also tend to be less expensive.