Evaluation of PetrifilmTM methods for enumeration of aerobic flora and coliforms in a wide range of foods

C. DE W. BLACKBURN, C.L. BAYLIS AND S.B. PETITT. 1996. Petrifilm^TM is a ready-to-use alternative to traditional microbial enumeration methods. The Petrifilm^TM Aerobic Count Plate (ACP) and Coliform Count Plate (CCP) were compared with standard methods for the enumeration of the aerobic mesophilic flora and coliform bacteria in 91 foods covering a wide range of different food commodities. There was good correlation between the Petrifilm^TM ACP and the standard aerobic colony count method ( r = 0.989) and between the Petrifilm^TM CCP and the standard Violet Red Bile Agar plating method ( r = 0.872). In both cases, the Petrifilm^TM methods had a better repeatability than the standard methods. The Petrifilm^TM ACP and CCP were shown to be practical and accurate alternatives to standard enumeration methods in a wide range of foods, with benefits of saving time, labour and incubator space.