Recovery of clostridium perfringens in the presence of an oxygen-reducing membrane fraction

The recovery and growth rates of pure cultures of C. perfringens were evaluated on media to which an oxygen-reducing membrane fraction (ORMF) had been added. C. perfringens ATCC 12917 reached stationary phase more rapidly in fluid thioglycollate medium (FTM) plus ORMF than in FTM alone. Three strains of C. perfringens were incubated in tryptose sulfite cycloserine (TSC) agar with and without ORMF. Recoveries were greater in media incubated aerobically with ORMF than in other formulations incubated aerobically or anaerobically. Recovery of the organism from inoculated and uninoculated foods was also evaluated. In inoculated foods, the organism was usually recovered in greater numbers using TSC+ORMF and aerobic incubation than with TSC and anaerobic incubation. Of thirty-five raw meat samples tested, C. perfringens was recovered from twenty-two samples using TSC+ORMF compared with eighteen using TSC alone. Organisms inoculated into beef stew were subjected to heat and cold stress for various periods. In all cases TSC+ORMF effected a greater recovery of viable C. perfringens