ReviewListeria monocytogenes in cheese and the dairy environment remains a food safety challenge: The role of stress responses

- In cheese Listeria monocytogenes finds a proper environment to mount tolerance responses.
- These responses assist its presence in cheese and persistence in dairy processing environment.
- These responses can also have implications on the behaviour of the pathogen in the host.
- The control of the pathogen in processing conditions persists as a challenge.

Dairy products, in particular soft cheeses, pose a major concern to the dairy industry and public health authorities as they are the leading source of listeriosis outbreaks, a severe foodborne infection affecting pregnant women, children, elderly and immunocompromised people, with a high (20-30%) mortality rate. Cheeses offer a suitable environment for the survival and growth of Listeria monocytogenes, allowing this pathogen to display tolerance responses that can favour its presence in cheese and persistence in dairy processing plants. Extensive food safety regulations in the EU towards prevention of contamination of dairy products with L. monocytogenes have been implemented. However due to the specific abilities of this pathogen to overcome the processing hurdles, its control remains a challenge. Compliance with the Good Manufacturing Practices, observation of Hazard Analysis Critical Control Points (HACCP) and the surveillance of the pathogen in the cheese processing environment are crucial to provide consumers with a safe product. This review aims to provide an overview on the current knowledge about the potential for the transmission of L. monocytogenes in cheese and its abilities to overcome the challenging processing conditions and implications for the behaviour of the pathogen in the host.