Marco Zappia ducks as he crosses the slightly-too-short threshold into the sauna in his office. A lanky 6-foot-2, he has to watch his head.
Having round-the-clock access to one of those build-your-own sauna kits that became so popular during the pandemic isn't just a perk of the job. Zappia, 30, and his team, 3leche, retrofitted the cedar cube into a kind of thermal cave, with 70% humidity and three heat zones that nudge along the careful cultivation of one very special kind of mold called koji.
Koji is the key ingredient in many of the food and drink experiments taking place inside the new 3leche Fermentation Lab in northeast Minneapolis' Food Building. Adding the fungus, which grows on starches, to raw ingredients and giving the mixture the time and space to ferment — that is, to undergo a chemical change — yields entirely new foods packed with depth, with umami, with funk. With koji's help, plain old soybeans, rice and wheat become mouthwatering miso, sake and soy sauce.
Employing a centuries-old Japanese technique for food transformation and preservation to make, say, an ancient Roman recipe for garum, a fish sauce-like condiment — and using only Minnesota-made ingredients — is one of the multifaceted ways 3leche's lab is breaking new, hyperlocal ground in an age-old tradition.
With the lab's opening this past winter, along with other efforts by area food and beverage experts, the Twin Cities is witnessing a 21st-century fermentation renaissance. After a processed-food-induced lull in the United States, practitioners, hobbyists and researchers are noticing increased consumer interest in fermented foods, whether because of the health or environmental benefits, or because, as Zappia says, "it's just deliciousness."
Fermentation involves adding a starter culture of living organisms — bacteria, yeast or mold — to foods. Those microbes find fuel there. They feed off the sugars and starches in the food, breaking them down into alcohols and acids that chemically alter the food's entire identity. Milk turns to yogurt, grapes to wine.
It's a complete reinvention. The process can be tumultuous, almost violent, at the micro level. Under an airtight seal, there could be foaming and bubbling and frothing. When making sake, for example, one stage of the conversion looks like rocks are tumbling in the tank.
Changing foods' chemical properties can be just as challenging as changing minds. "Instead of looking at mold as something to be scared of," Zappia says, "you can look at it like this has been happening for centuries."