Conventional wisdom dictates that lagers are clean and crisp, nearly devoid of yeast-derived flavors. Beers fermented with Brettanomyces, on the other hand, are all about what the yeast can do: fruit and funk and farmhouse flavors.
So how could the two ever coexist? What seems like an oxymoron actually isn’t, nor is it anything new. Both of New Belgium’s base beers for its wood cellar program, Felix and Oscar, begin with lager yeast, and rumor has it that a lot of the saccharomyces (brewer’s yeast) strains present in Cantillon bottles are actually lager strains. So while this practice is nothing new, the resulting beers are more recently being labeled as Brett or farmhouse lagers.
Take three examples from the past year: GoodLife and Ale Apothecary’s collaboration Brett Lager; Arizona Wilderness’ Blanc Farmhouse Pilsner; and Creature Comforts and Jester King’s collaboration Mutualism Southern-style Farmhouse Lager.
All begin as one style or another of lager. Brett Lager was born as a Dortmunder; Blanc as a straight-forward pilsner; Mutualism as a pilsner brewed with locally grown wheat and grits. All three beers could have ended their fermentation journeys after the lagering process (in fact, Creature Comforts kegged off some of the base Mutualism pilsner and the staff of both Creature Comforts and Jester King drank through it as-is). Not stopping there, the brewers decided to add Brettanomyces, and in some cases additional wild/souring bacteria, to further ferment the beer.
“Who the heck Brett ages a lager? Let’s take a long beer and make it even longer,” jokes Ty Barnett, GoodLife’s owner.
The goal of initial lager fermentation, says Creature Comforts’ wood cellar and specialty brand manager Blake Tyers, is to create a neutral palette on which the Brett can express itself. Because lagers ferment cleanly, without an ale yeast’s phenol and ester by-products, flavors produced by the Brett really shine through.
“We looked at a paper from Chad Yakobson [founder of Crooked Stave and formerly the author of the Brettanomyces Project], his early stuff was theorizing on how if you had less esters and phenols, then the secondary fermentation, once the Brett got involved, it would show more mature flavors more quickly,” Tyers says. “That was originally our intent, that the Brett would show its own characteristics more clearly.”
Arizona Wilderness founder Jonathan Buford found a similar result with Blanc.
“Dosing the bottles with Brett was unique because this was an already dry beer,” he says. “We needed Brett to eat dextrins as there were very little sugars left from the initial fermentation. This stresses the Brett out and it funk-ified the beer rather quickly, which was the biggest surprise.”
If Brettanomyces flavors (and some acidity, in Mutualism and Brett Lager) dominate the three beers, why even use the word lagers to describe them at all?
“It was to initiate a conversation with the consumer so they can learn more about the process of these beers. [With our] mixed culture program, we only roll out a handful of bottles every year and each one is kind of a chance to talk to people about different processes,” Tyers says. “The name was basically to get a conversation started. And to show people that it’s not just some infected batch of beer that turned out this way.”