Julian Shrago is behind the bar at Beachwood & Brewing, a pub in Long Beach where he makes some of the most sought-after beers in the West. He leads me out back, down a side street, and into another alley, to a space that he and his business partner, Gabe Gordon, the chef at Beachwood, built for this new experiment: the Blendery, a 4,500-square-foot brick-and-wood-beamed warehouse devoted to the making and study of sour beer.