Filter Media Comparison for the Removal of Brettanomyces bruxellensis from Wine

Abstract

Brettanomyces bruxellensis is a wine-spoilage yeast of significant concern to wine producers, and its removal by filtration is not fully understood. The aim of this work was to compare the efficacy of filters, having different compositions and micron ratings, to remove B. bruxellensis from wine. Wines inoculated with a B. bruxellensis strain were used, and the U.S. Food and Drug Administration guidelines for filter validation for aseptic processing were followed. Polypropylene filters of 0.6 and 1.0 µm ratings yielded wines with high Brettanomyces cell counts. No cells were detected in wines filtered through polyethersulfone filters of 0.45, 0.65, and 1.0 µm, or through X grade glass microfiber filter. This work showed that different filter compositions with similar micron ratings result in variable retention of B. bruxellensis, highlighting that filter media are relevant for removal mechanisms, and pointing to the importance of a complete characterization of filter media when addressing Brettanomyces removal from wine.