Underestimation of total-coliform counts by the membrane filter verification procedure.
Coliforms, primarily Citrobacter freundii, gave negative verification results in the total-coliform membrane filtration test. The organisms produced gas from lactose in brilliant green bile broth but not in lauryl tryptose broth. The discrepancy was related to the peptone sources used in the media.
D002954:Citrobacter / Q000254:growth & development / Q000302:isolation & purification*; D003470:Culture Media; D005374:Filtration; D014871:Water Microbiology
D003470:Culture Media