Plate Count Agar w/ 1.2% Agar is recommended for the determination of plate count of microorganisms in food and dairy products. It is recommended by APHA for the isolation of microorganisms in milk and other dairy products. This medium can be used where gel of 1.2% concentration is desired for plate count of microorganisms. For detection of mesophilic bacteria it is incubated at 30°C for 72 hours. For thermophilic bacteria it is incubated at 55°C and 6.5°C for 10 days for psychrophilic bacteria.
1. Buchbinder et.al (1951) Public Health Reports:66: 327.2.American Public Health Association, 1978, Standard Methods for the Examination of Dairy Products, 14th ed., APHA Inc. Washington, D.C.3.ISO 4833:1991 Microbiology –general guidance for the enumeration of microorganisms – Colony count technique at 300C.