Laboratory Procedure MFLP-43
Health Protection Branch
Microbiology Research Division
Bureau of Microbial Hazards, HPB
Postal Locator: 2204A2
Ottawa, Ontario K1A 0L2
This method is applicable to the enumeration of viable Enterobacteriaceae in accordance with the requirements of Sections 4 and 7 of the Food and Drugs Act. This revised method replaces MFLP-43 dated May, 1988.
This method has been shown to produce satisfactory results with naturally-contaminated foods for the detection of
Enterobacteriaceae (11.1-11.4). The MPN method applies in the analysis of foods containing small numbers of coliforms, since the sensitivity is not limited by the amount of food homogenate that can be introduced into a Petri dish.
This method estimates the numbers of viable Enterobacteriaceae per g or mL of product. A portion of the product is mixed with a specified agar medium and incubated under specified conditions of time and temperature. It is assumed that each viable microorganism will multiply under these specified conditions of incubation and give rise to a visible colony which can be counted.
See Appendix A of Volume 3.
See Appendix B of Volume 3.
1) 0.1% Peptone Water.
2) Petri dishes, glass (100 x 15 mm) or plastic (90 x 15 mm).
3) 1-, 5-, and 10-mL bacteriological pipettes, sterile.
4) Water bath or air incubator for tempering agar, 44-46░C.