Coliform colonies may begin to appear at 6 hours of incubation as discrete yellow zones indicating colony forming units (CFUs). Presumptive coliforms may be be recorded at 14 hours. Confirmed coliforms will appear as red colonies associated with gas.

The Petrifilm Plate Advantage

In today’s environment of heightened focus on food safety and increasingly stringent quality requirements, labs are under pressure to provide tests that are fast, reliable and consistently accurate. Petrifilm Plates have demonstrated consistent performance that has been cited globally with more than 200 certificates, recognitions, validations, and peer-review publications. For almost 40 years, food safety professionals around the world have put their trust in Petrifilm Plates. That’s because Petrifilm Plates have streamlined, standardized and simplified the process of microbial quantitative indicator testing, improving productivity and helping ensure the highest levels of product quality.