PLATE COUNT AGAR (STANDARD PLATE AGAR)

Plate Count Agar is used for determination of plate counts of microorganisms from samples. This media was formulated and described by Buchbinder et al. Plate count agar is also suitable for determining bacterial count in food and water, indicating microbial contamination. This culture medium complies with the specifications given by ISO 4833-1 & 2:2013 and APHA. The medium consists of Tryptone which provides nitrogen, vitamins, minerals and amino acids essential for growth. Yeast extract is a source of vitamins, particularly the B-group. Dextrose is the fermentable sugar providing carbon and energy. Agar acts as a solidifying agent.

Plate Count Agar is commonly used with pour plate technique in which diluted samples are combined with molten medium to achieve an even distribution of colonies. Plate Count Agar is used to estimate viable microbial load by counting colony forming units after incubation. It is commonly used in routine microbial monitoring in dairy and water testing. The accuracy of results is dependent upon the correct dilution and incubation conditions. Colonies can be seen clearly with this method and counting is easy. Confirmation tests may be necessary depending upon the type of microorganisms that may be isolated.

For determination of plate counts of microorganisms in foods, water, waste water and also from clinical samples