Flanders Red Ale This beer is from the evil brewer who likes to walk on the dark side and embrace wild yeast and bacteria. Ketser is a deep red ale fermented with Brettanomyces, Lactobacillus, and Pediococcus. The result is a sour and tartly acidic beer with fruit flavors of dark cherry, plum and currant. It offers a refreshing mouthfeel with a deeply complex character. Welcome to the dark side.