RTE meat and Listeria monocytogenes
Ready to Eat Meat (RTE) and Listeria monocytogenes
In addition to its ubiquitous occurrence in the environment, Listeria monocytogenes is able to withstand hostilities that many other bacteria cannot, such as high salt concentrations, refrigeration temperatures (below 4ºC), drying, freezing and absence of oxygen. At sufficient numbers, the bacteria can cause listeriosis, an illness that can present serious and life-threatening symptoms. These traits make L. monocytogenes a particularly disparaged microbe in the food industry.
The Canadian Food Inspection Agency (CFIA) enforces compliance with the Meat Inspection Act and Regulations, among other food safety and quality regulations. The CFIA has published a number of reference materials for meat processors, including the Meat Hygiene Manual of Procedures, which contains guidelines for testing for the presence of microorganisms in ready-to-eat (RTE) meat products. The CFIA maintains the Food Safety Enhancement Program (FSEP), which is intended to aid in the development and implementation of HACCP (Hazard Analysis Critical Control Points) in all federally registered establishments. HACCP is particularly of importance in meat processing plants and is consequently widely used by this industry. This food safety assurance program follows the progression of meat as it is processed and distributed, identifies locations at which contamination is most likely to occur and establishes control methods to ensure that contamination does not occur. Monitoring, tracking and verification systems are maintained for HACCP plans.
During processing, RTE meats are thoroughly cooked to ensure that all harmful bacteria and most spoilage bacteria have been killed. However, RTE meats are commonly implicated in foodborne illness cases as these products are not re-heated prior to consumption. According to the CFIA, there are two programs in place for RTE meats in the context of Listeria testing, in addition to existing Good Manufacturing Practices (GMPs) for all meat products: environmental monitoring in federally registered establishments and product testing for imported RTE meat. Testing for L. monocytogenes in the environment of the processing facility is verified by the CFIA at least twice a year. Positive tests require further sampling, product tracking or holding, and/or immediate implementation of end product testing. There is a zero-tolerance policy for the presence of Listeria in imported RTE meats.
Post-processing contamination can occur before the meats are packaged. The bacteria then have the opportunity to proliferate in the package, particularly when the products are subjected to temperature abuse. Post-processing contamination can occur by:
Contamination of packaging equipment/material;
Contamination of food-contact surfaces and utensils;
Failure to separate pre- and post-processing areas within the facility;
Time-temperature abuse at the cooking/cooling stage;
Poor employee hygiene.
Though processors are ultimately responsible for ensuring the safety of their product, the food distribution chain presents many variables that complicate the assurance of a safe RTE product on the consumer’s plate.
The various routes that packaged products undergo before reaching a consumer’s plate include:
storage in warehouses;
distribution in refrigerated trucks from manufacturers to retailers, restaurants, and institutions;
further processing, packaging and/or storage at retail/restaurant/institution level (i.e. division of meat from individual packages into sandwiches);
distribution, storage and preparation by the consumer.
The CFIA specifies the sanitation and operating conditions required of all food transport vehicles in the Manual of Procedures for Meat and Poultry Products, reinforcing HACCP principles, where the vehicle must be clean and maintain correct holding temperatures. Retailers, restaurants and institutions receive specification sheets and labels with the product which outline its identity, other required labelling information, and holding conditions, such as “keep frozen”. Proper food handling at the retail/restaurant/institution level can be reinforced by training programs, increasingly available throughout Canada. Additionally, safety at the consumer level is reinforced by consumer education programs.
Canadian Food Inspection Agency. (2008). Food Safety Facts on Listeria. Retrieved fromhttp://www.inspection.gc.ca/english/fssa/concen/cause/listeriae.shtml
Canadian Food Inspection Agency. (2008). Meat Hygiene Manual of Procedures. Retrieved from http://www.inspection.gc.ca/english/fssa/meavia/man/mane.shtml
Department of Justice. (1990). Meat Inspection Regulations. Retrieved fromhttp://laws.justice.gc.ca/en/M-3.2/SOR-90-288
Food Safety Network. (2008). Fact Sheet: Listeria monocytogenes. Retrieved from http://www.foodsafetynetwork.ca/aspx/public/default_viewalldetails.aspx?languageid=1&contenttypeid=5&ID=443&docid=76
Health Canada. (2004). Policy of Listeria monocytogenes in ready to eat to eat foods. Retrieved from http://www.hc-sc.gc.ca/fn-an/legislation/pol/policy_listeria_monocytogenes_politique_toc-eng.php