On tap at Ambulance, sour tripel collaboration (fusing Jolly Pumpkin’s La Roja Amber Ale to Bastone’s Nectar Des Deux Tripel) utilizes banana-clove-sweetened tripel yeast to contrast dry oak barrel-aged lactic acidity. Sour lemon rot, oaken cherry tartness and green grape esters hover above musty earthen grains as well.