By Eric Gorski
The Denver Post
GOLDEN, Colo. - In a corner of the Coors empire, in what used to be a storage room for bags of malt, a group of brewers is experimenting with beer that never will be advertised in a Super Bowl commercial.
Oak barrels that once held wine are stacked on racks. Look closely at one, and you’ll notice a sticker from the Belgian brewer Cantillon, a source of inspiration. The humming sound is from exhaust fans partly reponsible for bringing Coors Light to the masses.
The beers slowly aging in the barrels are funky second cousins to the Silver Bullet - part of a wave of mouth-puckering yet drinkable sour beers capturing the interest of American craft brewers and drinkers.
Consumers are about to get their first taste of the efforts at AC Golden, the MillerCoors craft beer incubator best known for Colorado Native lager.
Limited quantities of three sours - an apricot, cherry and peach - will be available in 750-milliliter bottles exclusively at Mile High Wine and Spirits in Lakewood later this month for about $21.99 each.
”The biggest reason we are doing this is we like to drink these,” said AC Golden brewer Troy Casey, 28, part of a younger generation of Colorado brewers making well-received wild and sour beers.
”We’re doing it to experiment, to learn what drinkers like. This is a high price point. Is it going to sell quickly or just sit on the shelf?”
The brewery acquired its first barrels three years ago and kept its work quiet - one reason it became known as the Hidden Barrel Project.
”We didn’t want everyone knowing what we were doing out here,” Casey said. ”But probably the biggest reason was that we didn’t know if we were going to make a drinkable product.”
Sours encompass a family of beers, fermented with unpredictable wild yeast and bacteria, that are expensive and time-consuming to brew.
The Boulder-based Brewers Association recognizes 13 variations of American-style sours. A whiff of a sour beer inspires descriptions such as barnyard, funky, horsey - and, yes, baby vomit.
And this is supposed taste good? Yes, that is the point, Casey said: to create enjoyable sours.
To brew the Apricot, AC Golden starts by fermenting a ”base beer” in stainless steel tanks - a low-alcohol neutral beer Casey likens to a blank canvas. Next, the beer is moved into the barrels.
The brewers then add the co-conspirators: multiple strains of the wild yeast brettanoymces and various Lactobacillus, an acidifying bacteria that produces the sour character.
Therein lies a big risk to brewing sours: If cultures and bacteria contaminate other equipment, untold volumes of other beer could be lost.
After eight to 10 months in the oak, brewers shovel in 120 pounds of Palisade apricots per oak barrel, displacing a lot of beer.
About three months later, what emerges is a super-dry, slightly hazy, balanced not overwhelmingly fruity beer that is only 5.5 percent alcohol by volume, very drinkable for being so complex.
Casey said AC Golden’s decision to brew fruit-based sours was in keeping with the brewery’s emphasis on local ingredients. The Kriek, for instance, features Montmorency cherries from Hotchkiss.
Other sours maturing in the barrel room - including a dark sour and aged saison - may get a special release in bottles or go to local beer bars, said Aimee Valdez, an AC Golden spokeswoman.
The American sour beer renaissance can be traced to the California brewers Russian River and Lost Abbey, as well as New Belgium in Fort Collins, which introduced its Flanders red ale, La Folie, in 1999.
There are now sour-specialty breweries such as Jolly Pumpkin in Michigan and Cascade Brewing in Portland, Ore. In Colorado, Trinity Brewing, Odell Brewing and others brew fine sours.
Yet sours are unlikely to break through on the scale of, say, India Pale Ales because of their high cost, limited quantities and acquired taste.
”If a lot of people are doing it in small quantities, there might be a good variety of sours. But they’re always going to be expensive and in limited supply,” said Kevin DeLange of Dry Dock Brewing in Aurora, which is aging a sour apricot in chardonnay barrels.
Casey has another motivation: to shed AC Golden’s stigma ”of just being part of MillerCoors.”
The son of Coors’ manager of applied brewing technology, Casey started as a Coors tour guide at 20, earned an undergraduate degree in chemistry but ”didn’t know what I was going to do with it.”
He caught the brewing bug, apprenticed at Bristol Brewing in Colorado Springs, earned a master’s in food science at the University of California, Davis, and worked briefly for Anheuser-Busch before returning home and joining AC Golden.
”His beers are extremely authentic - very, very Belgian in character,” said Jason Yester of Trinity Brewing in Colorado Springs. ”I heard a lot of criticism. ‘It’s just going to be another Blue Moon, a dumbed-down version of a white beer.’ That’s completely not true.”
No, Casey and his AC Golden colleagues are making true Belgian-inspired sour beers using wild yeast, bacteria and Colorado fruit, all from a room in the Coors brewery that is not so hidden anymore.