Comparison of Brands of Membrane Filters for Recovering Beer Spoilage Microorganisms¹

1 Presented at the 42nd Annual Meeting, Milwaukee, May 1976.

Abstract

Six brands of membrane filters (Gelman, Membra-Fil, Millipore, Nuclepore, Oxoid, and Sartorius) were evaluated for recovering contaminating microorganisms from beer. All filters were of the 0.40 to 0.45-μ pore size. Three different lots were tested for each brand. Beer samples were inoculated with typical contaminant microorganisms, and these were then filtered and recoveries were calculated. Five of the six brands were generally equivalent. Only one brand had a consistently lower recovery. All of the brands tested were consistent from lot-to-lot, but showed considerable variation from organism-to-organism.

• Contaminants
• Enumeration
• Filtration