Focus your control efforts
The FDA recommends focusing your control efforts on the raw materials and ingredients that are most likely to contain pathogens like Listeria. In fact, they say that you should treat any raw (or vulnerable) materials as if they are carrying those pathogens.
Identify suspect materials
Factors that impact the potential for an ingredient to be a source of contamination include:
- The nature of an ingredient, including intrinsic factors such as pH and water activity;
- The manufacturing process for the ingredient;
- Supplier approval programs, programs that follow the practices described in this guidance for control of L. monocytogenes, and verification programs.
In addition to these, any ingredients not properly treated for L. monocytogenes also poses a significant risk in your supply chain. Listed below are some of the most common treatment methods. If your raw materials have not undergone any of these steps, consider a change in your food safety strategy.
- Aseptically processed and packaged;
- Retorted (e.g., canned);
- Ethylene oxide treated or irradiated in the package;
- Pasteurized (or equivalent treatment) in the package;
- Other approved lethal technologies (in the package)
Again, in the absence of adequate information about the risk presented by a particular ingredient, we recommend that you assume that the ingredient could be contaminated with L. monocytogenes.
Containing the risk
One of the best ways to prevent contamination is to identify all of the raw materials which could potentially be a host for L. Monocytogenes and treat them with a listericidal control measure. The best time to apply such treatments is while the ingredient is raw, or at the in-process stage during mixture.
The FDA also recommends establishing treatment protocols with your suppliers; this can serve as another step to prevent outbreaks and contamination. While spot checks are a great part of everyday quality assurance, they (on their own) do not serve as an adequate replacement for a hands-on approach. Onsight audits, periodic inspections, and developing procedures for vetting and selecting suppliers are a better (and safer) way to ensure food safety.
In fact, according to new FDA standards, as of September 2017, most large food manufacturers are expected to develop these kinds of supply-chain measures. For more information, consult the FDA’s PCHF guidelines.