THE ENUMERATION OF COLIFORMS AND ESCHERICHIA-COLI ON NATURALLY CONTAMINATED BEEF - A COMPARISON OF THE PETRIFILM(TM) METHOD WITH THE AUSTRALIAN STANDARD

Petrifilm(TM) PEC was compared to Australian Standard (AS) methods for the enumeration of coliforms and Escherichia coli on 50 naturally con taminated beef samples from three meal works. The standard methods con sist of a 3-tube most probable number test or a direct plate count on tryptone bile agar for E. coli, and violet led bile agar and the most probable number test for coliforms (AS 1766.2.12.1984 and AS 1766.2.3. 1992). No significant difference was found between the methods, except that the count of E. coli on the direct plate method with a resuscita tion step was significantly higher than the count on Petrifilm(TM), mo st probable number or direct plate count without resuscitation. Copyri ght (C) 1996 Elsevier Science Ltd