polyvinylpolypyrrolidone

Polyvinylpolypyrrolidone (PVPP) is an insoluble, crosslinked polymer derived from N-vinyl-2-pyrrolidone. The polymer is formed by crosslinking vinylpyrrolidone monomers to create a network with a high surface area suitable for adsorption. Unlike its soluble cousin polyvinylpyrrolidone (PVP), PVPP resists dissolution in water and most solvents due to crosslinking, which makes it useful as a fining agent in liquids.

PVPP is widely used in the beverage industry to remove polyphenols, tannins, and other phenolic compounds that can cause haze, color instability, or off-flavors. In beer, wine, and fruit juices, PVPP binds tannins and phenolic acids, helping to stabilize clarity and flavor during storage. The binding occurs through hydrogen bonding and hydrophobic interactions at the polymer surface. After treatment, PVPP is removed by filtration or sedimentation.

PVPP is typically supplied as granular beads or as a powder and used in batch or flow-through clarifying steps. The dosage and contact time depend on the product and the desired level of clarification; following treatment, filtration typically removes the polymer before packaging.

Regulatory and safety aspects: PVPP is approved for use as a processing aid in many jurisdictions and is considered inert, with negligible absorption by the human digestive system. It is distinct from soluble polyvinylpyrrolidone (PVP) and is valued for its adsorptive properties rather than tissue uptake.