3M launches faster E. coli and coliform count plate

The 3M Petrifilm Rapid E. coli/Coliform Count Plate is a two-in-one indicator test that gives an E. coli and total coliform count in 18-24 hours.

Plates are sample-ready eliminating the step of preparing media/agar dishes.

Proprietary formulation​

The 3M Petrifilm Rapid E. coli/Coliform Count Plate is a selective sample-ready-culture-medium system which contains a cold-water-soluble gelling agent, 5-bromo-4-chloro-3-indolyl-D-glucuronide (BCIG) – an indicator of glucuronidase activity and a tetrazolium indicator to facilitate colony enumeration.

The proprietary formulation consists of growth promoters, selective and differential indicators along with inducers and facilitates faster E. coli/coliform recovery and detection with a shorter time to result.

Sailaja Chandrapati, 3M senior product development specialist, said the count plate can detect any strain of E. coli that produces beta glucuronidase.

Atypical strains that are non-beta glucuronidase producing will be detected but will appear as coliforms.

“The plate is designed to work with a wide variety of food matrices including meat and poultry, produce, dairy products and more, as well as with environmental swab and sponge samples. No specific food samples are excluded, however process water and irrigation water samples have not been evaluated in our laboratory,” ​Chandrapati told FoodQualityNews.

“The 3M Petrifilm Rapid E. coli/Coliform Count Plate has a proprietary formulation that tests for beta glucuronidase-producing strains of E. coli and colors them blue. ​

“This enables the easy differentiation of the E. coli from other coliforms, which are colored red. Customers count the number and prevalence of the colonies grown to determine whether the sample is contaminated.” ​

Major concerns for producers​

Chandrapati said E. coli and coliform organisms are major concerns for food producers.

“E. coli is an opportunistic pathogen, responsible for over 100,000 illnesses and 90 deaths every year in the US alone. Coliforms are a broader class of organisms that include E. coli as well as other lactose fermenting indicator bacteria from fecal, soil and environmental samples. ​

“Coliforms serve as important quality indicators in food safety testing – as the distribution and prevalence of coliforms in a product can point to more serious contamination problems, including but not limited to E. coli.” ​

3M’s previous Petrifilm E. coli/Coliform Count Plates gave confirmed E. coli results in 24-48 hours. It was awarded AOAC Official Methods of Analysis (OMA).

The firm is pursuing third-party AOAC/MicroVal validation (ISO 16140-2 protocol) for its technology.

Over the past six months, the team has been testing the plate with food producers and reference labs from Korea and Thailand to Canada and the US.

Customers mentioned they found it easy to use and benefitted from not having to manually prepare agar or use special equipment to enumerate.

3M said the ability to simultaneously obtain E. coli and coliform results and differentiate between different colonies has made a big impact for customers.

Chris Somero, 3M Food Safety marketing manager, said: “This new plate is an all-in-one, easy-to-use chromogenic solution that can immediately boost productivity and accelerate their products’ time to market.” ​

3M also held a food safety symposium earlier this month with Frank Yiannis of Walmart, Martin Wiedmann from Cornell University and DeAnn Benesh, 3M.