Cryofine is purified isinglass in a convenient powder form. It is added to beer at the end of fermentation to speed maturation, and improve filtration and clarity by fining out yeasts and protein particulate. For the purposes of rapid dissolution, enhanced performance, and long shelf life, the isinglass in Cryofine has been pre-hydrolyzed and freeze-dried. CRY 151 also contributes to the actions of both silica gels and PVPP. It is regularly used in cask conditioned beers as auxiliary finings for solids settling and clarification.