POLYEX PVPP

Polyvinyl Polypyrrolidone (PVPP) adsorbs the oxidizable and polymerizable fraction of the phenolic compounds.

POLYEX PVPP improves wine stability:

• By removing the phenolic compounds liable to oxidize and polymerize and that may affect color, limpidity and the organoleptic qualities of the wines.
• Its selectivity and affinity sometimes make it complementary to treatments with casein or bentonite, but it cannot be replace by these two products.
• Wine polyphenols often form complexes that are soluble with proteins. A decrease of protein content in wines after treatment with POLYEX PVPP is frequently observed.

This Polyvinyl Polypyrrolidone polymer selectively adsorbs polyphenols according to a decreasing polymerization gradient, thus wine polyphenols will be adsorbed in this order:
Anthocyanin compounds –> catechins –> flavonols –> phenolic acids
By formation of hydrogen linkages between the phenolic hydroxyl group and amide linkage with PVPP.
Its adsorption capacity depends on the number of potential sites of hydrogen linkages whereas adsorption selectivity depends on the site location.