As craft beer continues its unprecedented growth, “firsts” are becoming increasingly hard to come by. This Friday, however, Waconia’s Schram Vineyards Winery & Brewery will become the first modern brewery in Minnesota to release a beer aged in a concrete fermenter.
A few years ago, Aaron Schram was on a trip to California and visited a couple wineries using concrete vessels to age wine. He thought the mineral qualities the vessels imparted to wine might work well with Minnesota grapes, so he decided to build one of his own. But before he had the chance to put his theory to the test, it occurred to him that few brewers were experimenting with concrete fermentation, so he decided to give that a try first. The lack of information he was able to find online backed up his suspicion.
Schram worked with Cemstone to build the vessel, and they consulted with a California cement company to get the specs just right. The fermenter was constructed with fine granite sand instead of the standard concrete mix that includes larger pieces of gravel.
Schram’s concrete fermenter is jacketed with glycol lines so they can control the fermentation temperature. Even standard jacketed stainless steel fermenters have hot and cool spots, Aaron said, and one of the benefits of the concrete tank is that it keeps a consistent temperature throughout. It has a removable cover, making wild, spontaneous fermentation an option for the future.
Aaron said he wan’t exactly sure what to expect out of their first test batch. Not surprisingly, though, he said the aromatics of the beer were noticeably changed, and the mineral qualities from the tank came through so strongly they opted not to release that first batch. Despite the finer concrete mix, about one-third of the test batch was absorbed into the walls of the tank. The second time around, they filled it with water first to hydrate the vessel before draining the water and transferring beer into it.
Armed with some lessons learned, the next beer Schram put into the fermenter is the one that will be released on Friday. Concrete IPA, as they’re calling it, is a 7.5% ABV, 90 IBU IPA brewed with Chinook, Cascade, and Centennial hops. It spent a little over two weeks fermenting and Schram’s tasting notes for the beer read, “Rich caramel in color, this is a medium to darker bodied IPA. A fresh citrus aroma hits the nose right away, which gives way to earthy mineral tones upon first sip. Drier on the finish.” The beer will be available on draft and in growlers at Schram’s taproom beginning this Friday, July 21.
As for what beer the concrete container might see next, Aaron said he’d like to try a saison. And taking advantage of the open-topped vessel, perhaps a spontaneously fermented beer will be in the works further down the line.