Health Canada approves DuPont’s BAX E. coli test for composited samples

Canadian beef processors and independent laboratories that test ground beef for E. coli O157:H7 now have the means to speed testing, increase throughput and reduce their overall cost per test.

Health Canada’s Microbiological Methods Committee has extended its approval of DuPont’s BAX System real-time PCR assay for E. coli O157:H7 to cover composited samples of ground beef weighing up to 375g.

The assay is a rapid screening method for detecting presumptive E. coli O157:H7 in individual 65g samples of raw ground beef and 375g samples of raw beef trim. In addition to typical strains, the BAX System assay can detect non-motile strains and other atypical O157:H7 variants, according to DuPont.

BC (before compositing)

The assay was originally approved by Health Canada in April 2011. It is published as MFLP-76 in the Compendium of Analytical Methods: Laboratory Procedures for the Microbiological Analysis of Foods.

“Until now, laboratories were required to enrich, prepare and process each 65g sample as an individual test using the BAX System method,” Kathy Wilson, Canadian business manager for DuPont Nutrition & Health Diagnostics, told FoodProductionDaily.

“Using the newly approved compositing method, however, laboratories can physically combine up to five different 65g samples to enrich them as a single 325g sample,” she said. “After enrichment, the combined samples are prepared and processed as a single test sample with the BAX System method. That allows for greater throughput and a lower overall cost per test.”

Flexible tool

Wilson said customers who perform a large number of pathogen tests every day “…value a detection system that maximizes sample throughput and offers the greatest level of flexibility.”

However, a laboratory does not need to be a certain size to use the BAX System for composited samples, she noted. “Any company that tests raw ground beef or beef trim for the presence of E. coli O157:H7 can use the compositing method with the BAX System for their regular testing.”

Wilson said that in addition to Health Canada, the US Department of Agriculture’s Food Safety and Inspection Service (USDA-FSIS) has adopted the BAX System E. coli O157:H7 assay for testing meat products using sample sizes up to 325g. FSIS allows for a 325g sample to be created by combining smaller representative portions of equal size to create a single larger sample for testing.