Boom Island Brewing Company
The first beers ever made on earth were spontaneously fermented. Long before humans discovered that microscopic bacteria and yeast were responsible for alcohol, they knew that some ambient force was turning their sugary grain water into delicious ale. Even now, brewers of Belgian lambics rely on the native microflora of the Zenne valley to inoculate their beer.
Boom Island Brewing’s Oude Funk, the first in the brewery’s Spontaneous Series released back in September of 2015, was reverent (though not beholden) to that tradition, using an abbreviated open-fermentation with two different “cocktails” of yeast and bacteria, including one that head brewer Kevin Welch cultured from the yeasts native to his neighborhood in Minneapolis.
“Day two, day three, the fermenter’s left wide open so it does experience an open-fermentation because it didn’t necessarily get that in a coolship,” Welch explains, of the method for Oude Funk. “Open-fermentation is about four days and then it went into the barrel from there and that’s really where the important part of fermentation goes.”
Oude Funk is not a Lambic—for one, it’s not made in Belgium, but it also uses prepared cultures instead of ambient microflora. Still, his process would be familiar to a Lambic- or gueuze-maker. Oude Funk is a blend of three-, two-, and one-year-old oak-aged beers. The porous surface of oak helps the microbes strike a perfect, if precarious, balance. It gives the microflora a surface to burrow into and just enough oxygen to help them breathe.
“It for sure does continue to mature in the bottle because there are still living microbes in there,” Welch says. “In fact, the regular brewer’s yeast that was used for the re-fermentation in the bottle, what will happen is that yeast will autolyze and it will decay, and then the bacteria will start to eat that yeast.”
Boom Island released the second beer in the Spontaneous Series, Triple Brett, in May 2016. As the name implies, Triple Brett was fermented simultaneously with three different strains of Brettanomyces yeast, then aged for 10 weeks in French oak red wine barrels. As noted in our first taste of Triple Brett, the flavor is mild and mellow, with a deep mahogany color and a sip full of dark fruit and floral notes that finishes dry and clean.
Oakhold Farmhouse Brewery
It might be tempting to call the upcoming beers at Oakhold Farmhouse Brewery “wild” ales, but as we’ve learned, the terminology in this area doesn’t tell the whole story. “Wild” implies that you don’t know what you’re getting. At Oakhold, it’s a little more precise than that.
“It’s not magic, it’s truly not. It’s about figuring out the organisms,” says Caleb Levar, Oakhold co-founder. “The magic of yesterday is the science of today. I don’t want to give the false impression that we understand it all, or that there’s never bad batches. But instead of throwing up your hands and hoping, you try to understand the variables better in the pursuit of making better beer.”
Levi Loesch brewed his first beer, an oatmeal stout, with his dad for a 21st birthday present. He met Caleb Levar through a mutual friend a few years later, and a couple of Levi’s fruit-based sour beers made it to a tasting at Caleb’s apartment.
“I was under the impression that only Russian River and Allagash can do these well,” he recalls. “This idea that you can do it well as a homebrewer was amazing.” Caleb graduated with a microbiology degree (perfect for culturing and understanding those bacteria) and has gone on to assistant brewership at Fair State Brewing.
Oakhold is in the process of building an entirely mixed-fermentation brewery in Northern Minnesota (check out their first journal entry on the subject). Their goal is to strike a middle-ground between the terribly funky sours and the clean, approachable kettle sours. Their normal process will involve a primary fermentation with standard brewer’s yeast (Saccharomyces), and then barreling in American oak with a wide range of other funky microbes. A rye saison will be their primary brew to begin with, because of its potential for variation.
Oakhold will be growing wheat and barley on their property, eventually planning on making an “estate” beer, probably in the Lambic style. They’re also growing apricot, raspberry, plum, pears, cherries, and strawberries on the property to experiment with as well.