Alias: Polyvinylpyrrolidone crosslinked, PVPP CAS number: 25249-54-1 Properties: White or slightly yellow powder with easy flow and hygroscopic properties. Molecular formula (C6H9NO)n Introduction to cross-linked POvidone PVPP Pvp-p, which is a polymer of the soluble compound PVP (polyvinylpyrrolidone) with insoluble versions of water and beer, PVPP is an amide polymer that binds to polyphenol compounds with a higher affinity than the proteins present in beer, which gives PVPP excellent properties as a chemical stabilizer for beer. If finely granular, high surface area PVPP is dispersed in beer, a large proportion of the dissolved polyphenols in beer will bind to the PVPP particles and subsequently be filtered out. Brewers want to remove these polyphenols because they react with beer proteins over time to form insoluble complexes that make beer cloudy. This type of stabilizer is called an adsorbent. PVPP can be used in two different ways to stabilize beer purity. The…