Beer has come a long way since the Bavarian beer purity law established the four basic ingredients of beer. Nowadays, anything goes: pumpkin, cherry, chocolate, even chipotle chili peppers have found their way into bottles of our favorite adult beverage.

This summer, brewers have pushed the envelope even further. Beer shelves have welcomed new brews with flavors of lime, banana, blueberry and, strangely enough, crème brulee.

Part of the explosion in new flavors is due simply to experimentation by no-holds-barred craft brewers whose first instinct is to push the envelope on traditional beer styles. With hops prices going through the roof, some of them are turning to other ingredients - fruit and spices - for added kick.

More notably, though, America's big guys are dabbling like mad scientists, too. They've learned that many of their potential customers - especially women - are no longer satisfied with the flavor of mainstream American lager.

Like 'em or lump 'em, this new generation of flavors is part of a remarkable evolution that, in just a few short years, has redefined what a beer can be. Here's a sampling:

Bud Light Lime. This is Anheuser-Busch's answer to Miller Chill, which was basically Miller's answer to all those Corona bottles with a lime wedged into the neck. It's reportedly A-B's most popular new beer since Michelob Ultra.

It has a bigger lime flavor than Chill, with a tingly fizz that's geared to the soda pop set.

Budweiser Chelada with Clamato. You know how, on the morning after, your second Bloody Mary just sits there for an hour, melting the ice? It seemed like a good idea at the time, but by now it's 1 in the afternoon, your headache is mostly gone, the Phillies are on the tube and you're ready for a beer. You suck on the cocktail straw one last time and your mouth fills with a watery, lightly alcoholic version of V-8.

That's what Bud Clam tastes like.

Next time, I'll kick it up a notch with Tabasco and try it without the hangover.

Southern Tier Crème Brulee Stout. Pour a glass of this imperial milk stout, and you know what's coming before your first sip. You're swamped by a HUGE waft of vanilla, immediately sending you back to that afternoon you swiped a sip from mom's bottle of (70 proof) vanilla extract.

Besides all that vanilla, it's made with lactose sugar, crystal malt and candy sugar, which gives it that crackling, bitter burn caramel taste you enjoy in a perfectly torched crème brulee.

Unfortunately, this is beer, not dessert, and I couldn't swallow more than three or four sips. Southern Tier brewer Phin DeMink warned me, "It's the kind of beer you should share with a couple of friends over dessert."

I took him literally. I poured the rest of the bottle into a pan, reduced it over a low flame and ladled it onto a dish of bananas and pineapple.

Wild Blue. Most blueberry beers offer only a slight hint of fruit - a fresh, mellow aroma to remind you of ripe berries. This lager grabs you by the neck and forces you headfirst into a vat of smashed fruit and won't let you up till you're blue in the face.

It reminded me of a melted grape Popsicle.

Made by Blue Dawg Brewing of Baldwinsville, N.Y., Wild Blue is actually a stealth label from Anheuser-Busch. At 8 percent alcohol, it's as strong as A-B's Hurricane High Gravity malt liquor.

Bananatana. Made with bananas and sultana grapes by Holland's Brouwerij Drie Horne, it sounds like a Martha Stewart kitchen disaster. I mean, bananas in beer?

But think again. Think about that German hefeweizen that you like so much, with its hallmark banana aroma produced by yeast fermentation.

Here, the brewer uses real bananas, and the flavor is in the finish, delicate and not overwhelming. It reminded me of a fine saison whose peppery bite had been replaced by a peeling fruit.

Congrats to Fred Kline of Coatesville, who brought home a silver medal from the American Homebrewers Association national homebrew competition, the largest in the world. Kline, the sole medalist from Pennsylvania, won for his homemade weizen beer.

The Phils are on the road this weekend, but the suds will be flowing during the first ever Beer Fest at the Ballpark tomorrow. The event, with 18 local breweries, features a bizarre keg pyramid contest in which the winner will be served at McFadden's at Citizens Bank Park for the rest of the season.

Tix: $30/$40 door. 3-7 p.m. Info: www.mcfaddensballpark.

com. *

Joe Sixpack by Don Russell appears weekly in Big Fat Friday. For more on the beer scene in Philly and beyond, visit www.joesixpack.net. Send e-mail to joesixpack@phillynews.com.