Pucker up to the bar

Sour beers, the funky final frontier

A golden sour beer aged in oak barrels with black currants from all-sour brewery, The Rare Barrel, in Berkeley.

A golden sour beer aged in oak barrels with black currants from all-sour brewery, The Rare Barrel, in Berkeley.

PHOTO courtesy of the rare barrel

Bitter and sweet have been the essence of most beers for centuries. Still, these basics of the flavor spectrum weren’t enough for some craft brewers, who in the past decade have introduced to the American beer market a curious style of beer called a “sour.” These brews have bitter hops, and they have sweet malt, but the dominating flavor, thanks to a living consortium of bacteria cultured in the aging beer, is tart, acidic sourness.

Russian River Brewing Co., in Sonoma County, is widely credited as a leader in the sour-beer revolution. Here, brewer Vinnie Cilurzo has brought us renowned sour ales like Supplication and Consecration. But other breweries have become almost equally reputed for making beers tart enough to pucker the faces of the most seasoned beer drinkers. There is The Rare Barrel, in Berkeley, which makes all sours. Almanac Beer Co., in San Francisco, also focuses on sour beers. Nationwide, and in Europe, the style is now well-recognized as its own category in specialty beer aisles.

Although you may never have tasted one, sour beers are not a new concept. Rediscovered in the current century, sour styles such as lambic, kriek and gueze were first made in Belgium ages ago—and probably initially by accident. The style owes itself to bacteria in the genera Lactobacillus and Pediococcus, as well as yeast in the genus Brettanomyces. All of these microbes produce flavors ranging from funky to downright sour. Winemakers, in fact, often fear these critters, which can create ruinous off-flavors in a wine. Worse, they can easily infect the porous wood of barrels, rafters and walls and become long-term residents of a facility. Eliminating these organisms may be impossible short of burning the place down.

Chico’s Sierra Nevada Brewing Co. has been reluctant to experiment too earnestly in the sour beer style due to the risk of contaminating the brewery, according to communications manager Ryan Arnold. While a limited release of a sour beer could be possible someday, he says, the risks of making funky beers, and of a bacterial outbreak infecting other beers, are too high.

Bill Manley, another rep with Sierra Nevada, aptly summed up the hazards: “Any time beers using traditional brewer’s yeast are made side-by-side with beers using other yeasts [like Brettanomyces] or bacterial strains, extreme caution must be taken to prevent cross-contamination. Any porous materials can become impregnated with the bacteria or foreign yeasts, which can infect or out-compete the traditional brewer’s strains.”

Making these beers on a regular and large-scale basis can be done, he says (and Sierra Nevada did brew a very tightly controlled one-off collaboration with Russian River a couple of years ago called BRUX, a wild ale using Brettanomyces yeast). “It is a gamble, though, and a small error can lead to a very large problem that is difficult to fix,” Manley says.

At Russian River, on the other hand, Cilurzo has made sour beers a main part of his business, and with no second facility to accommodate them. Some are so tart that newbies to the style might cringe at first taste. Cilurzo also brews acclaimed IPAs and other conventional styles that, if a wayward microbe found its way in, would be ruined by sourness.

“We have a lot of systems in place to keep funky and nonfunky beers separated,” he explained in an email. Color-coded tools and equipment are reserved for either sour or nonsour beers. “There are [also] rules that all the brewers follow when they are working with barrels. Once they touch something funky they are not allowed into the main cellar. We also never do funky work on bottling days. I even go as far as to have separate shoes and boots.”

At The Winchester Goose bar in Chico, owner Rob Rasner always keeps at least a handful of sour beers on tap and a dozen or more in bottles.

“Most people are skeptical at first of the style, but it’s surprising how many palates this flavor profile fits,” Rasner says. He notes that while Pediococcus and Lactobacillus bacteria create very sour flavors, the qualities of a Brettanomyces beer are simply “funky,” comparable to horse blanket, hay and barn. A good beer to start with for newbies might be Evil Twin’s Femme Fatale Brett, a funky Belgian-style IPA. You also can find many sours, including occasionally some from Almanac, at Spike’s Bottle Shop.

Want a real face-turner? Then try Rodenbach’s Grand Cru, a Belgian red ale aged in oak vats. The beer is affected by Brett yeast, as well as bacteria—and it’s really, really sour.