It's IPA Day - get hoppin'

TODAY IS IPA Day, or — since it's mainly a social-media phenomenon — #IPADay.

Which is to say it's an occasion to drain a pint or three of India pale ale, then tell the world all about it. Right now, there are thousands of beer drinkers at IPA tap takeovers and other events across the country, entertaining themselves by taking photographs of foam-filled glassware.

It sounds silly, especially when you consider that, according to the Brewers Association, last year's inaugural event generated roughly 10,000 tweets with the official #IPADay hashtag.

I'll admit I'm not entirely up to speed on Twitter, but I do understand what makes IPAs so popular: hops, baby — plenty of 'em.

Humulus lupulus, the plant that provides the necessary bitterness in beer, is the signature ingredient of India pale ale, a 200-year-old British style that grew out of the nation's colonization of India. The style was never particularly popular in America, especially after World War II, when brewers aggressively toned down the bitterness of their mainstream products. By the 1960s, they were boasting about their "smoother" flavor. In the '90s, Keystone Light was bashing "ewww … bitter beer face!"

In retrospect, it's not surprising that hops would come to embody the entire craft-beer renaissance.

Microbrewing was a revolution led largely by counterculture types whose products were the opposite of mainstream beer. Where BudMillerCoors was innocuous, Sierra Nevada Pale Ale was assertive.

Where the big guys used hops almost anonymously to balance the sweetness of malt, these new brewers celebrated the flower's essential oils and resins. They experimented with bold types (Cascades, Chinook, Nugget) to enhance aroma and flavor and, importantly, that bitter snap. We started to hear terms like the "hop back," which infuses oils into the hot wort, and "dry-hopping," the post-fermentation addition of aroma hops.

Shortly, our palates were transformed.

Where simple pale ale once seemed sufficiently challenging, we soon demanded stronger and more bitter India pale ale — an Americanized version that relied less on a solid malt body, and more on an increasing variety of hops: Simcoe, Amarillo and the current darling, Citra.

We guzzled, and brewers responded with even more hops: the imperial or double IPA.

IBUs — international bitterness units — became part of the lingo, with brewers outdoing each other for bragging rights. Dogfish Head Brewery came up with Randall the Enamel Animal, a hop-filled cylinder connected to a draft line, to add even more flavor.

The triple IPA was inevitable.

What I didn't see coming was how brewers would eventually regard IPA as a mere starting point in their recipes. Sure, it happened before, when porter and stout were transformed with the addition of flavorings or fruit or smoked malt or barrel aging. But IPA? I never thought those distinctive hops could make room for other flavors.

Yet the Brewers Association now says IPA "represents the pinnacle of brewing innovation with its broad spectrum of diverse brands, subcategories, and regional flavor variations."

Traditionalists argue that many of these variations aren't really India pale ale. But that train already left the station. Today, beer drinkers will celebrate #IPADay with black IPAs, white IPAs, rye IPAs, Belgian IPAs and even fruit IPAs.Grab your smartphone and try 'em.

Traditional English: The classic, malt-forward IPA is as subdued as Queen Elizabeth. Try Meantime India Pale Ale, worth a couple of extra bucks in a large bottle.

American: As assertive and bitter as Newt Gingrich when he's not on his meds. Try Weyerbacher Last Chance IPA, completely unbalanced with huge aroma of grapefruit.

Double or imperial: Bigger is better, baby. Try Stone Ruination Tenth Anniversary IPA, a one-off that's about 50 percent stronger than normal Ruination, in bombers that proclaim, "Ruining palates for ten years."

Triple: Even bigger is even better. Try Founders Devil Dancer, with 12 percent alcohol by volume and 112 IBUs.

Belgian: Tropical yeast flavor plays off the citric quality of the hops. Try Manayunk St. Alpha, with the aroma of apricot and banana.

Black: It looks like a stout, but without the heavy body or malt-forward flavor. Try Southern Tier Iniquity, now available with two other IPAs (2XIPA and Unearthly) in a new SuperPack variety case.

White: Essentially an over-hopped Belgian-style witbier. Try Blue Point White IPA, especially refreshing in ice-cold cans.

Rye: Barley is supplemented with rye, for a peppery bite. Try Hoppin' Frog Hopped-Up Goose Juice, which is not, in fact, brewed with foie gras.

Sour: Fermented with Brettanomyces yeast for added funk. Try Green Flash Rayon Vert (if you read French, that's a redundancy), reminiscent of Belgium's Orval Trappist Ale.

Fruit: Think tart, not sweet. Try Boxcar Mango Ginger India Pale Ale, a West Chester brew now available in bottles.

Anything goes: You name it, somebody is adding it to an IPA. Try Sierra Nevada Flora IPA, brewed with rose petals, in the just-released Beer Camp variety case.