ICMSF methods studies. VIII. Comparative study for the enumeration of Clostridium perfringens in foods

Abstract

Four methods were compared in an international comparative study for the enumeration of C. perfringens: the SFP (Shahidi-Ferguson perfringens) agar (A), TSC (tryptose-sulfite-cycloserine) agar (B), SC (sulfite-cycloserine) agar (C) and neomycin blood agar (D) methods. The confirmed C. perfringens counts were slightly lower for D than for A-C. The percentages of presumptive colonies confirmed as C. perfringens were essentially the same in each method. The relative numbers of nonspecific colonies were the lowest in C, followed by B, D and A. The methods were also compared for simplicity and for aspects associated with the recognition and selection of presumptive colonies.