ListeriaMonitoringInFoodEstablishments

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Nov 7, 2019 - Foods

ListeriaMonitoringInFoodEstablishments

Since Listeria are microorganisms that are widespread in our environment, persist in biofilms, and can multiply in foods even under unfavorable environmental conditions, these bacteria are regularly detectable in relatively many food groups such as meat and meat products (BfR, 2017). If the legal food safety criteria for Listeria monocytogenes from Regulation (EC) No. 2073/2005 on microbiological criteria for foodstuffs are exceeded, products on the market must be recalled. Numerous examples of this can be found in the European Rapid Alert System for Food and Feed (RASFF) (European Union, 2018).

Food business operators whose products may be contaminated with Listeria monocytogenes based on their properties are required by legal mandates in EU hygiene law (Article 4 Paragraph 3 of Regulation (EC) No. 852/2004 on foodstuffs in connection with the provisions of Regulation (EC) No. 2073/2005 on microbiological criteria for foods) and due to due diligence requirements to conduct appropriate self-monitoring.

These obligations pertain not only to the conduct of food examinations but also to the conduct of environmental investigations. For in Article 5 Paragraph 2 of Regulation (EC) No. 2073/2005 on microbiological criteria for foods, it states: “...Food business operators producing ready-to-eat foods which may pose a risk to public health due to Listeria monocytogenes shall examine samples from the processing areas and equipment for Listeria monocytogenes within their sampling plan...”

Since there are no concrete legal specifications regarding the scope of an environmental monitoring for Listeria monocytogenes, one can be guided by guidelines or recommendations. The “Guideline for Good Practice for Conducting Microbiological Self-Checks in the Self-Production of Ready-to-Eat, Pre-Chopped Fruit and Vegetable Products in Retail” recommends an annual environmental investigation for Listeria monocytogenes on a cleaned and disinfected spot per year (BLL, 2016).
Other German hygiene guidelines do not yet contain information on the scope of environmental monitoring for Listeria monocytogenes.

The following aspects were considered in the implementation of this Listeria environmental monitoring and the interpretation of results:

• Listeria monocytogenes are bacteria that are widespread in our environment and therefore occur regularly in many raw animal and plant foods (BfR, 2017; BfR 2018). These germs also regularly occur in food businesses as they are, for example, introduced into the operation via raw materials and humans
• the goal of a food business must be to prevent permanent colonization with Listeria monocytogenes within the company. These areas are especially moist areas where cleaning and disinfection do not occur regularly or cannot be fully reached during cleaning and disinfection. These include, for example, places at drains and evaporators or evaporator trays of cooling systems
• individual positive findings with Listeria monocytogenes are practically unavoidable in many food businesses that handle unpackaged raw animal and/or plant-based foods. It is crucial to prevent permanent colonization or biofilm formation with Listeria monocytogenes through hygienic measures
• in an environmental examination for Listeria monocytogenes in food establishments, it is therefore reasonable to obtain information on the following aspects: how frequently Listeria monocytogenes is found in the environment, where they are located, and how successful the cleaning and disinfection measures undertaken have been. Therefore, within the framework of monitoring, investigations during ongoing operations as well as after cleaning and disinfection are beneficial. However, the investigations during operations should predominate
• depending on the investigation site, using sponges or swabs during sampling is sensible. For larger surfaces, sponges are preferable to test areas of 300cm², for example. In hard-to-reach areas such as crevices, it is necessary to work with swabs
• laboratory investigations conducted must use suitable qualitative methods following enrichment to ensure high sensitivity and detect the lowest levels of germs

Literature

• Bund für Lebensmittelrecht e.V. (BLL) / Bundesverband des Deutschen Lebensmittelhandels e.V.: Guideline for Good Practice for Conducting Microbiological Self-Checks in the Self-Production of Ready-to-Eat, Pre-Chopped Fruit and Vegetable Products in Retail (12/2016), last accessed: 02.10.2018 (BLL, 2016)
• Federal Institute for Risk Assessment (BfR): Zoonosis Reporting by BfR. Pathogens of Zoonoses in Germany in 2015, last accessed: 01.10.2018 (BfR, 2017)
• Federal Institute for Risk Assessment (BfR): Press Release by BfR from 27.09.2018. Listeriosis: Rare, but Dangerous for the Elderly, Pregnant, and People with Weakened Immune Defenses, last accessed: 01.10.2018 (BfR, 2018)
• European Union: RASSF Annual Report 2017, last accessed: 02.10.2018 (European Union, 2018)
• Regulation (EC) No. 852/2004 of the Commission of 29 April 2004 on food hygiene (OJ L 139 of 30.04.2004, p. 1) in the current version
• Regulation (EC) No. 2073/2005 of the Commission of 15 November 2005 on microbiological criteria for food (OJ L 338 of 22.12.2005, p. 1) in the current version

In our laboratory, we regularly conduct testing for Listeria monocytogenes. We have both a 24-hour rapid method, a 48-hour rapid method, and the ISO method in the accredited area in operation. We provide you with fast and reliable results.

For questions, our customer advisors are very much at your disposal.