(WASHINGTON POST) - To a mainstream beer drinker, the list of featured beers at a recent Washington-area festival might sound like a truly weird beer geek's Christmas list: a crisp, briny gose that gets its flavour from local oyster liquor - the liquid you slurp from the half shell - and is fermented with yeast cultured from the shells of oysters; tart Berliner weisse-style beers brewed with blood orange, mango and passion fruit, or a mix of cucumber and mint, that taste more like juice bar treats; and a sour Beligan-style brown ale with half the spices in your local supermarket, including star anise, ginger and grains of paradise.
Yet hundreds of people paid US$60 (S$81) to US$75 each to wander around the Make It Funky Festival, an annual festival at Denizens' Silver Spring, Maryland brewery and beer garden, on Sept 30, sampling almost 100 wild-fermented and sour beers from 36 breweries, including Free Will's 2014 Kriek Sour, a wild ale with notes of sour cherry pie, and Allagash's Hive 56, which spends 18 months in large oak vessels called foeders with Brettanomyces yeast and the brewery's own honey, and tastes of fig, strawberry and a hint of vinegar.
The popularity of this event is a sign of the growing power of the sour, which remains a niche style in terms of overall beer consumption but is of increasing importance to brewers who are trying to differentiate themselves in a marketplace swamped by a continuing tide of (India pale ale) IPA and golden ale. It's a way for American breweries to put their own stamp on venerable European styles and open their audience's minds to a new range of experiences. And as sours find more devotees and space in taprooms, the variety of styles is also helping to expand craft beer's consumer base beyond stereotypical hopheads: According to a 2016 Nielsen survey of craft beer consumers, women are 75 per cent more likely to prefer sour ale than men.
It's the spectrum of flavours that appeals to beer fans such as Jen Murphy, 35, of Silver Spring, who attended her second Make It Funky festival with her husband, Brian, 34. Jen first fell in love with lambic beers from Belgium at a bar in New York City, but, she says, "I really like the diversity of beers at the festival: dark, light, fruity, barrel-aged." Her favorites included Union's Old Pro Tea Time Tangerine, a gose infused with tangerine, and Bluejacket's Blue Highway, a blend of barrel-aged saison and wild-fermented ale that was aged on fresh Virginia blueberries. "I tend to order the fruity sours, but I really like any beer that hits you in the jaw on the first sip."
"Jen got me into sour beers," says Brian, whose beer of choice is a hoppy IPA. "To be honest, I was not a fan when I first tried them. . . . But I started trying more and more funky beers and started finding those I liked. I think the gateway to more of this style was Union's Old Pro Gose or the Brett IPAs where you get the funkiness but some good aroma hops." (His favorite, like hers, was the Old Pro.)
Sour beers are one of the most unlikely success stories in the current American craft scene. Traditional German and Belgian styles, such as gose and lambics, are centuries old. Their trademark sharp, acidic flavours come from the presence of lactic bacteria, including Lactobacillus, Brettanomyces and Pediococcus, during fermentation.
Modern brewers approach the creation of these beers in different ways: Some allow wild yeast and bacteria to enter the wort, a process known as spontaneous fermentation, while others carefully control the yeasts that find their way into the brew. Some brewers make sour beers with these wild organisms only in the brew kettle, while others prefer to leave fermenting beer in tanks or wooden vessels for months while nature takes its course.
Hannah Gohde, a brewer at Free Will Brewing in Perkasie, Pennsylvania, remembers her first taste of oud bruin, a tart brown ale from Flanders, when she was in graduate school. "At first I was like, 'I'm not so sure about this,' and then I took another sip, and I was like, 'Yeah, this is so cool.'"
When Free Will began brewing sours a few years ago, Gohde says, it was "from a selfish standpoint. It was hard to find a great sour that was available for a decent price on the market." But more than that, she enjoys the process. "I like the creativity that goes into sours," Gohde says. "It's more of an art form than a science. You have all of these barrels and vessels and various styles of aging, and it's up to you to come up with a blend that fits into your vision."
Free Will now has "about 450 wooden vessels of various kinds" to age beer in a 1,579-sq m cellar, with beers ranging from traditional kriek lambics with cherries to key-lime sours aged in tequila barrels. Five times a year, Free Will hosts events dubbed Sour Sunday, putting at least 10 sours or wild ales on the brewery's 15 draft lines. (The next one is Oct 29.) "We get 600 or 700 people over the course of the day," Gohde says, with some driving for three or four hours for samplings.
Jun Rossetti admits she didn't know what sour beer was when she first visited Denizens a few years ago. "I don't keep up to industry trends," the Silver Spring researcher says. But after she told a bartender about her love of vinegar and citrus flavours, he steered her toward a sour ale. Now she's spreading the gospel: "My husband doesn't like sour beer - he's a hoppy IPA guy. He didn't get why I like it. He came (to the Make It Funky festival) last year and tried some beers and said, 'I get it now.'"
One barrier to entry might be the terminology: "Sour" is not always a positive descriptor for beverages, outside of certain cocktails. And so many different styles now fall under the umbrella of sour that it's hard to know what's meant without context: A tart gose, made refreshing by the addition of coriander and sea salt? A lemony, face-puckering Berliner weisse?
The bright, acidic funk of a traditional gueuze? The sweet, woody tartness of barrel-aged blond Belgian ale? Or something else entirely?"I think it's a challenge with all the terms," says Allagash brewmaster Jason Perkins.
The Maine brewery has made some of the more interesting wild ales in the United States and was the first on this side of the Atlantic to use a large, open pan called a coolship to brew tart, complex Belgian-style ales through spontaneous fermentation.
"I think it's a confusing thing for the consumer. But I wouldn't want to tell a brewer, 'If you want to call it this, it has to go into one of these boxes.' That goes against craft brewing, frankly." At the same time, "I don't love the term 'sour beer,'" Perkins says. For some beers, especially those with what he perceives as "more nuanced" acidity, "to say, 'That's a sour beer,' it doesn't really describe that beer, it doesn't do that beer justice."
Whatever you call them, supermarket sales of sour beers tripled between 2015 and 2016, according to market research firm IRI, and are up an additional 9 per cent through August, says Bart Watson, the economist for the Brewers Association trade group. He thinks that is probably underselling the style's popularity because many sours are still most popular in brewery taprooms and others are counted in overall sales numbers in different categories: A summer-only gose might be counted as a seasonal rather than a sour, for instance.
Still, some larger breweries have found success with more sour styles: Sierra Nevada's Otra Vez Gose was the fourth-best-selling new craft beer brand in supermarkets in 2016, according to IRI, and New Belgium's new Wood Cellar Reserve series of sour and wild ales has been gaining buzz in beer circles.
Sours are still a niche, Watson says, "but a fast-growing style and one that a lot of brewers think is going to be important in the future."
Melissa Reitkopp of Silver Spring got into beer by traveling to breweries across the country with her husband, Jeff Peters. She started drinking Belgian ales and then moved into Flanders red ales - "the more sophisticated ones hit your tongue in three or four different places," she explains.
Reitkopp and her husband attended their second Make It Funky this year and she wasn't surprised that the festival was more crowded. "People are getting more adventurous," she says. "I think sours bring in a segment of the population who aren't big beer fans. For friends who don't drink beer, sours are an interesting way to get people into beer."