Plate Count Agar (PCA), 500 g. Trypticase Glucose Yeast Agar, Standard Methods Agar
Trypticase Glucose Yeast Agar, Standard Methods Agar SPECIFICATION : Medium for aerobic plate counts by the surface inoculation method, according to ISO standards 4833, 8552, 17410 and IFU no. 6. FORMULA* IN G/L : Casein peptone 5.0 Yeast extract 2.5 Dextrose 1.0 Agar 15.0 Final pH 7.0 ±0.2 at 25 °C *Adjusted and/or supplemented as required to meet performance criteria. DIRECTIONS : Suspend 23.5 g of powder in 1 l of distilled water. Heat to boiling with frequent stirring. Distribute into suitable containers and sterilize by autoclaving at 121 °C for 15 minutes. DESCRIPTION : The Plate Count Agar formulation is according to that of Buchbinder et al. as recommended in their study of media for the plate count of microorganisms. The original formulation of the standardized agar for dairy microbiology has been modified in order to avoid the addition of milk. This new composition allows the growth of most microorganisms without any further additions. This medium's formulation is equivalent to that escribed by the 'Standard Methods for the Examination of Dairy products', the USP's 'Tryptone Glucose Yeast Agar', the Deutsche Landwirtschaft and to the APHA and AOAC's Plate Count Agar. This is the medium of choice for the plate count of any type of sample.