Aug. 18, 2014 4:45 p.m. ET
Owner Matthias Neidhart holds a glass of Zymatore beer and a glass of the beer in its original format. Andrew Hinderaker for The Wall Street Journal
With its barn, greenhouse and bucolic fields of camomile and berries, B United International Inc., from the outside, doesn’t look like a typical warehouse beer distributorship.
And inside the Oxford, Conn., facility, there is another anomaly: a room where beer is being aged not in huge industrial steel tanks, but in hundreds of hand-me-down wooden barrels. That is where B United, which distributes aficionado brands like Germany’s Schneider Weisse and Japan’s Hitachino, is giving some of its clients’ brew a secondary round of aging—in containers that formerly held wine, whiskey and other alcoholic beverages.
The Zymatore room at B.United International. Andrew Hinderaker for The Wall Street Journal
“Select beers can actually soak up the flavors and aromas of the spirit previously housed in the wooden barrel in a way that…makes it highly interesting,” said Matthias Neidhart, founder and owner of B United.
Mr. Neidhart is among a small, but growing cadre of respected artisan brewers using pre-used wooden barrels, in the belief that the residual flavors and lingering microflora from whatever liquid they previously held can enhance a beer’s aroma and taste.
Those elements don’t transfer from wood to beer automatically, brewers said, but are teased out during a secondary fermentation process involving wild yeast.
“Barrels that once stored a Syrah or Chardonnay to maturity can bring out so many more complexities in flavor,” said Zach Mack, co-owner of the Alphabet City Beer Co., an East Village bar that offers more than 350 varieties of craft brew.
The enthusiasm for barrel aging was first rekindled nearly a decade ago, when brewers discovered that aging beer in bourbon barrels could add tasty vanilla overtones to their porters and stouts. More recently, some have begun expanding their container repertoire, using barrels that have held everything from Sauternes and Scotch to brandy and rum, seeking flavor notes that range from sour to tannic.
New York area brewers are among the leading-edge wood-barrel users.
Garrett Oliver, brew master of the Brooklyn Brewery and editor of “The Oxford Companion to Beer,” said he is partial to bourbon barrels, which are typically made of virgin American oak and used only once before being sold. His brewery’s facility in the Brooklyn Navy Yard currently houses more than 2,000 wooden barrels for aging beer.
“Bourbon wood is quintessentially American, and that’s a big appeal for me,” said Mr. Oliver.
Brewmaster Ben Neidhart in the Zymatore room with barrels used to age beer. Andrew Hinderaker for The Wall Street Journal
Matt Monahan, co-owner of Other Half Brewing Co., which opened in January in Gowanus, prefers wine barrels. “If you age a beer in a bourbon barrel, it tastes like bourbon,” he said. Other Half is currently using barrels that once housed Zinfandel, Sauternes and even the cult California Cabernet Opus One.
Wooden barrels aren’t exactly new; for centuries, beer was stored and aged in them. But after Prohibition, the American brewery industry dramatically consolidated, and growing companies seeking larger-capacity storage with greater sterility turned to massive stainless steel tanks.
The return to wood-barrel use comes at a time of greater experimentation among craft brewers with more traditional, less industrialized materials and techniques. Some Pale Ale makers, for example, are using techniques like “dry hopping,” popular in the 19th century as a way to stabilize beer and enhance its flavor, by adding hops during the beer’s secondary fermentation.
Wooden barrels usually slow down the aging process. Basil Lee, co-owner of Finback Brewery, which opened in January in Queens, said his company ages beer in both bourbon and wine barrels and chose its 13,000-square-foot space because it had room for longer-term brewing projects.
“I have tasted beers where you wished that they had aged more,” he said. “We sought out a space that would enable us the freedom to age beers for a year or two if necessary.”
Many large-production commercial beers typically age for one month; some lagers take up to four, experts say.
Mr. Neidhart of B United said slower barrel aging allows natural processes to take their course, rather than artificially helping them along with, say, rigorous climate control.
“Conventional brewing is all about controlling the process,” said Mr. Neidhart. “We are trying to return the control to nature.” He ages some of his clients’ beers for two or three years.
“Clients ask us when their beer will be ready and we tell them we don’t know,” he said.
Owner Matthias Neidhart holds two bottles of Zymatore beer. Andrew Hinderaker for The Wall Street Journal
For all the effort, Mr. Neidhart said his barrel-aging program accounts for just 2% of his business, moving over 400,000 case-equivalents of beer annually.
And to be sure, barrel-aged beers are still a niche part of the $14.3 billion annual U.S. craft beer market. But their influence is spreading nationally. California craft breweries like The Bruery and Firestone Walker Brewing Co., for example, have recently launched extensive barrel-aging programs.
In New York, drinkers can find them in beer bars like Proletariat, Terroir and Owl Farm.
And some are beginning to show up in local restaurants. Other Half, for example, is brewing several barrel-aged beers exclusively for Roberta’s, a popular Williamsburg eatery. That is because barrel aging not only adds to overall complexity, said Mr. Monahan, but also tends to soften a beer’s finish over time, helping raise its food-friendly quotient.