Focus on Food Safety – October 2008

The CFIA issued a bulletin on Sept. 5 to manufacturers of ready-to-eat (RTE) meat products recommending additional sanitation measures to clean slicing equipment to address Listeria monocytogenes (LM) risks. I’d like to build on these recommendations with a number of other suggestions to help processors of products at risk of transmitting LM to manage the risk.

LM is a ubiquitous bug. If you look for it, you will find it. The CFIA requires processors to monitor for LM by carrying out a specific number of tests, but this is a bare minimum. If you find LM by sticking with the current regulations, there is a high probability that you may have a serious LM problem.

Individual LM tests cost from $15 (in-house) to $50 (single samples at a commercial lab). However, these costs can be managed by combining samples. It’s important to retain the individual samples should the composite test positive so you can go back to individual samples to discover which individual sample(s) are positive.

Prior to production, your priority in sampling should be food contact surfaces, including employees handling exposed product, food processing equipment non-food contact surfaces and any surface such as floors, drains and hoses, that accumulate debris that could harbour LM. Re-sample as many of these surfaces as is practical in the middle and at the end of the shift.

Standard sanitation measures alone are not always effective in controlling LM. Assuming equipment for high-risk products is restricted for that purpose (do not use the same equipment for raw and cooked products), here are some other, more aggressive, measures to consider: high-pressure and high-temperature washes with sanitizers; disassembly and chemical sterilization of all cleanable equipment parts used to process RTE products; aggressively sanitize floors and equipment prior to production; continuously sanitize food contact surfaces; do mid-shift clean ups and sanitizing of equipment that cannot be continuously sanitized during production; and provide sanitizer stations for sanitizing hands and small wares.

High-risk products such as RTE meats and minimally processed products which will be consumed as-is, should be on a hold-release program and/or a release-in-transit program. The cost of holding product while tests are done is insignificant when compared to the cost of a recall. The cost of analyzing products can be managed by combining samples of two or more pallets. However, it is critical that individual samples be retained for re-sampling if necessary.