Walking around the large barrel cellar at Wild Mind Artisan Ales with brewer Mat Waddell, it’s clear to see he’s having a hell of a lot of fun. The room is filled with equipment for experimentation: hundreds of oak barrels, six large foeders, a custom-built coolship, and a blending tank. Mat pinballs around the room, sliding his slender frame through the stacks of barrels, listing off the contents of what’s inside.
There’s barleywine in rum barrels; stout in whiskey barrels; lambic-style ale in red wine barrels; golden sour in a giant foeder; a dark sour in the blending tank with raspberry puree, ancho chiles, and cocoa nibs; the brewery’s very first barrel that holds saison from the summer of 2016. He explains the beers with excitement, and has great stories for each brew. In this room, every beer is on its own journey.
In the taproom, Mat and I talk over a collection of beer samples—from super tart, light-colored wild beer to a dark, complex farmhouse ale. He speaks quickly, bounding from point to point, describing his process as “a half-scientific, half-artistic/rustic brew approach to brewing beer.” Many of the beers have been allowed to spontaneously ferment with naturally occurring yeast. Others have fermented with one of Mat’s several house blends of yeast, most of which contain a percentage of wild yeast that he captured and cultivated.
Mat’s obsession with yeast does not come from academia. He didn’t study microbiology or food science in school; his degrees are in mechanical engineering. But as a homebrewer, Mat was interested in experimentation and eccentric ideas from his first batches. Amazed by the mutations of yeast over generations, he started learning more about yeast collection and propagation. “The first time I cultivated wild yeast—about five years ago—it was from a raspberry bush in my backyard. I used that yeast to ferment a beer, and it turned out beautiful the first time. I kept the culture going and it lives on today in all of these beers.”
It’s with a devilish grin and an air of pride that Mat tells me the things that he does in the brewery would probably appall a lot of other brewers—starting with the yeast and how it’s pitched. “Sometimes I just open up barrels with my different vials of yeast; I’ll pitch a bit of this one in this barrel, and a bit of that one into another barrel. Other breweries may go for an exact volume at an exact temperature, and then get rid of yeast after a few generations,” he says. “Don’t get me wrong. We still put the yeast under a microscope to check for viability and health, and I do go for certain pitch quantity. It’s not likely we’re just shooting in the dark here, but we certainly are not afraid to see new beers come from keeping it loose.” It’s this careful chaos in fermenting that yields the variety of beers in Wild Mind’s taproom.
The thing that sets Wild Mind apart from other Minnesota breweries, and a personal point of pride for Mat, is the coolship. Coolships are not common in American breweries, although they have been used for production of Belgian lambic beers for centuries. Wild Mind’s coolship looks like an oversized steel bathtub and holds 310 gallons, or one full brew from the brewhouse. After being boiled in the kettle, scalding hot wort is transferred directly into the coolship where it rests to cool overnight, exposed to all the natural yeast and bacteria in the room. Once cooled, the beer can be transferred directly into barrels to ferment under the influence of the microbes it’s collected (plus whatever microbes might be in the barrels). Or, it can be transferred into stainless steel fermentors to ferment with its ambient yeasts or with one of Mat’s house blends.
Mat has added another untraditional layer to the uncommon use of the coolship, sometimes choosing to transfer the boiling hot wort directly onto other ingredients such as fresh hops for a long cooling steep. Last Halloween, he coolshipped a traditional barleywine over farm fresh pie pumpkins and spaghetti squash that had been split open.
“After cooling overnight with the pumpkins, we racked it back into stainless and pitched our house sour ale blend of yeast,” says Mat. “In this case, I didn’t want it to 100 percent spontaneously ferment, I didn’t want it to be insane funky—and I wanted a fairly quick turnaround.” Fairly quick, in this case, meaning one year; he hopes to release it for Halloween 2018. Not exactly what most brewers would think of as quick.
Patience is a necessity for Mat’s style of brewing. There is still beer in barrels from when Wild Mind first opened nearly 18 months ago that potentially won’t be ready for another 18 months. Once a month, he and Wild Mind staff go through the entire wood cellar, not only tasting each barrel to gauge its progress but also testing the pH and gravity.
“You start to predict where it’s going to go,” Mat said. “It’s not like the whiskey industry, where they know they can put it into barrels for 35 years and it will be epically awesome. With sour beer, after a year, it could get very vinegar-like. You have to keep checking and decide when that perfect moment has been reached.”
Mat’s mechanical engineering background kicks in when barrels are ready to be emptied and packaged. “Right now we brew three or four times a week. One—because we have a busy taproom. And two—we have this really big wood cellar and we have to keep full. With my engineering brain, I get this sense of satisfaction and completeness when every barrel is full and everything is status quo. Then the next day, everything gets fucked up—we need to empty this barrel, we need to fruit this beer, we need to get that beer on tap. It’s at that point that we need to figure out how to get the room back to status quo again.”
Mat knows that the majority of people that come to their taproom are not aware of—and may not even care about—the science and technique at play inside the brewery; they just enjoy the beer, which is, of course, job number one. However, he specifically built out the brewery in a way that he hopes invites curiosity—the wood cellar is viewable from a wall-sized window, the brewhouse and packaging area can be seen from smaller windows in the taproom—and encourages education on advanced and less common brewing topics like spontaneous fermentation, turbid mash, and use of aged hops. “I chat with my team weekly about certain topics,” says Mat, “so they can have one-on-one conversations with our guests. Most people are perplexed about what we are doing and are in shock when they learn.”
What makes his work at Wild Mind all the more meaningful to Mat is a family connection he feels to the process, particularly when it comes to the coolship beers. To him, the coolship pays homage to his great-grandparents and how they used to ferment things at their Minnesota farmhouse. “Back in the 1920s, granny would make wines with whatever she could get her hands on. Great-grandpa would ferment in a bucket with a towel over it. My dad and my aunt like to tell me, ‘Your granny would be so proud of you.’”