perpetua sour coolship beer from 100% spontaneous fermentations, aged 1 month on fresh Tuscan citrus zests (orange, lemon, grapefruit, citron) of local ancient varieties. Ka is our perpetua: worts from different coolship are added to the perpetua (a kind of solera) one after another, and spontaneously fermented thank to the resident microflora. raw materials: local organic barley malt, local organic wheats of evolutionary populations, aged hops, local citrus. no sour pitch, nor yeast, nor brett, nor bacteria were added