Petrifilm

Petrifilm is a brand name of prepared culture media sheets used for microbial testing, manufactured by 3M. These self-contained, ready-to-use plates consist of a thin film coated with dehydrated culture medium, nutrients, and a tetrazolium indicator dye. They are designed for enumerating specific types of bacteria and other microorganisms in food, beverages, and environmental samples.

Petrifilm plates simplify the process of microbial testing by eliminating the need to prepare agar plates, autoclave media, and sterilize equipment. To use Petrifilm, a sample is diluted and then applied to the plate. The plate is then incubated at a specific temperature for a designated period of time. The indicator dye reacts with the metabolic activity of the growing microorganisms, producing visible colonies that can be counted.

Different types of Petrifilm are available for various applications, including:

• Aerobic Count Plates: For the enumeration of total aerobic bacteria.
• Coliform Count Plates: For the detection and enumeration of coliform bacteria.
• E. coli/Coliform Count Plates: For the differentiation and enumeration of E. coli and other coliform bacteria.
• Staph Express Count Plates: For the rapid enumeration of Staphylococcus species.
• Yeast and Mold Count Plates: For the enumeration of yeasts and molds.

Petrifilm is widely used in the food industry, clinical laboratories, and environmental monitoring facilities for its convenience, ease of use, and consistent results. Their standardized format contributes to reduced variability and improved data quality in microbial testing.