Sours are arguably the hottest field in craft beer today—in fact, I daresay you wouldn’t get much argument to the contrary from any beer geek with his or her ear to the ground. Just about every brewery with the capability is trying to get its hands on used wine barrels and unused oak casks for the purpose of inoculating their ales with lactobacillus, brettanomyces and all manner of wild yeast. But even with so many new tart beers hitting the market, it’s rather easy to forget how wide the range of flavor profiles the broad term of “sours” actually implies.
In short, just because it’s tart, that doesn’t mean it’s going to be reminiscent of all or even most other beer soured with the same bacteria. The range of tartness alone can vary from barely perceptible to face-puckeringly sour, depending on the time that bacteria is given to work its magic. Even the grape varietal formerly contained in a wine barrel makes a difference and imparts some of its own character.
Illinois’ Two Brothers Brewing has been around for almost 20 years now, but they’re still relative newcomers to the sour game. Putting their jumbo-sized oak foudres to work in recent years, they’ve slowly matured several beers in “Project Opus,” a sour series that began with Tangent, a dark sour. Newest is Fathom, simply labeled “sour ale,” a golden-orange wild ale that has spent two years in the foudres.