Acidic

isolated airborne yeast during Superstorm Sandy. “We have a multitude of organisms in that stew, and we’ve also added some lab culture to it. Now it’s a combination of something we caught airborne and some cultures that we purposefully added,” Markowski says. “It’s taken on a life of its own.”

This stew was used to ferment Two Roads’ award-winning Urban Funk sour ale that aged in stainless steel for a year before its debut in 2013.

Another noteworthy house microbe blend was cultivated by Jesse Friedman, the cofounder and brewmaster at Almanac Beer Company in San Francisco, California, with a combination of dregs from favorite sour beers. “We threw a party, and everyone brought their favorites. We cultured the dregs from those bottles and added commercial bugs as well. There are too many beers to name—of course, there was beer from Russian River, Orval, Cantillon ... at least a dozen or two.”