Recycling of PVPP used in the wine industry: An opportunity for obtaining reusable PVPP and bioactive phenolic compounds

Abstract

Polyvinylpolypyrrolidone (PVPP) is a synthetic water insoluble polymer produced by cross-linking of polyvinylpyrrilidone. It is used as a fining agent in the wine industry for removing low molecular weight phenolic compounds. There are no available data on the worldwide use of PVPP in the wine industry; nevertheless, its estimated use in Portugal in 2016 for white wine fining was nearly 147 tons. Used PVPP ends up on the municipal wastewater treatment plants, and as it contains significant quantities of adsorbed polyphenols it has a detrimental environmental impact. Recycling of PVPP for obtaining fully reusable PVPP and phenolic compounds for the food, cosmetic and pharmaceutical industry would increase the sustainability of its industrial use. Therefore, the purpose of this work was to develop a simple, cheap and eco-friendly regeneration strategy for the re-use of PVPP and at the same time to obtain pure extracts of wine phenolic compounds in order to exploit new opportunities for recycling used PVPP. The performance of the recycled PVPP for white wine fining was the identical when compared to a new PVPP.