Isinglass Isinglass Isinglass () is a substance obtained from the dried swim bladders of fish. It is a form of collagen used mainly for the clarification or fining of some beer and wine. It can also be cooked into a paste for specialised gluing purposes. Its origin is from the obsolete Dutch "huizenblaas" – "huizen" is a kind of sturgeon, and "blaas" is a bladder, or German "hausen blas", meaning essentially the same. Although originally made exclusively from sturgeon, especially beluga, in 1795 an invention by William Murdoch facilitated a cheap substitute using cod. This was extensively used in Britain in
Trub (brewing) fermentation. It is composed mainly of heavy fats, coagulated proteins, and (when in fermenter) inactive yeast. The term has its origins in the German word "trübe" (also "trüb"), which means "cloudy", via the brewing and winemaking terms "Trubstoff" ("cloudy" + "material") and "Weintrub" ("wine" + "cloudy"). Trub (brewing) In the process of brewing beer, trub is the term used for the material, along with hop debris, left in the whirlpool or hopback after the wort has been boiled then transferred and cooled. Brewers generally prefer that the bulk of the trub be left in the whirlpool rather than stay in