Method for the regeneration of PVPP from a membrane filter retentate after clarification and stabilization of a yeast fermented beverage

A method of regenerating polyvinylpolypyrrolidone (PVPP) particles in preparing a yeast fermented beverage, comprising:

• (a) fermenting wort with a biologically active yeast to produce a fermented liquid containing yeast, alcohol, polyphenols and protein;
• (b) optionally removing yeast from the fermented liquid;
• (c) mixing the fermented liquid with single use grade PVPP particles to bind at least a fraction of the polyphenols and/or the proteins contained in the fermented liquid to the PVPP particles, wherein at least 80 wt. % of the PVPP particles have a diameter of 5-150 μm;
• (d) filtering the fermented liquid containing the PVPP particles over a first membrane filter having a pore size of 0.1-5 μm without employing a filter aid to produce a clarified fermented liquid and a first retentate containing PVPP particles;
• (e) combining the first retentate with an aqueous regeneration liquid to desorb polyphenols and/or protein from the PVPP particles, the aqueous regeneration liquid having a pH of at least 10.0;
• (f) filtering the combination of first retentate and regeneration liquid over a second membrane filter having a pore size in the range of 0.1-10 μm without employing a filter aid to produce a second retentate containing regenerated PVPP particles;
• and
• (g) optionally further refining the regenerated PVPP particles contained in the second retentate, and recirculating the regenerated PVPP particles to step (c);
• wherein macromolecular components contained in the first retentate of step (d) and/or retained on the second filter of step (f) are degraded using an oxidant.