SMMP - A MEDIUM FOR SELECTIVE ISOLATION OF MEGASPHAERA AND PECTINATUS FROM THE BREWERY

A selective medium for the isolation of Megasphaera and Pectinatus, designated ''SMMP,'' was developed. The basal medium contained lactate, which served as the sole source of carbon, and reducing agents that promoted growth of anaerobes. Brewing yeast and wild yeasts were inhibited by an excess amount of cycloheximide (Actidione). Alcohol in the beer sample inhibited coliforms and lactic acid bacteria, and other commonly occurring gram-positive brewery bacteria were completely suppressed by the combination of crystal violet and sodium fusidate. The incorporation of these four agents into a specially designed anaerobic broth made it possible to develop a selective medium for the isolation of the two most damaging beer spoilage bacteria-Megasphaera and Pectinatus.