Vegetarianism and beer a yeasty flavour. Finings are used to clear the beer of yeast – there are a variety of agents used as finings, including silicon dioxide, gelatin, polyclar, and isinglass. Isinglass is the most common fining used to clear cask ale. Isinglass is produced from the swim bladders of fish, usually sturgeon, though also those in the polynemidae, sciaenidae and siluridae families; as it is an animal product, cask ale cleared with isinglass is not considered vegetarian. A brewer may also use some form of animal product in the later stages of beer processing, such as glycerol monostearate, which is used
Country Joe and the Fish was responsible for coining the group's name—a reference to Josef Stalin and to Mao Zedong's description of revolutionaries as "the fish who swim in the sea of the people". McDonald, who had recording experience, began utilizing Arhoolie Recording Studios to record four songs split equally between the band and a local folk musician, Peter Krug. It was during this time at Arhoolie Records that Country Joe and the Fish's folk sound and political protest prowess—an amalgam of their own Guthrie-influenced material and their folk music roots—began to emerge. The band's side of the EP featured two originals by McDonald, an