Persistence of microbiological hazards in food and feed production and processing environments

Abstract

Listeria monocytogenes (in the meat, fish and seafood, dairy and fruit and vegetable sectors), Salmonella enterica (in the feed, meat, egg and low moisture food sectors) and Cronobacter sakazakii (in the low moisture food sector) were identified as the bacterial food safety hazards most relevant to public health that are associated with persistence in the food and feed processing environment (FFPE). There is a wide range of subtypes of these hazards involved in persistence in the FFPE. While some specific subtypes are more commonly reported as persistent, it is currently not possible to identify universal markers (i.e. genetic determinants) for this trait. Common risk factors for persistence in the FFPE are inadequate zoning and hygiene barriers; lack of hygienic design of equipment and machines; and inadequate cleaning and disinfection. A well‐designed environmental sampling and testing programme is the most effective strategy to identify contamination sources and detect potentially persistent hazards. The establishment of hygienic barriers and measures within the food safety management system, during implementation of hazard analysis and critical control points, is key to prevent and/or control bacterial persistence in the FFPE. Once persistence is suspected in a plant, a ‘seek‐and‐destroy’ approach is frequently recommended, including intensified monitoring, the introduction of control measures and the continuation of the intensified monitoring. Successful actions triggered by persistence of L. monocytogenes are described, as well as interventions with direct bactericidal activity. These interventions could be efficient if properly validated, correctly applied and verified under industrial conditions. Perspectives are provided for performing a risk assessment for relevant combinations of hazard and food sector to assess the relative public health risk that can be associated with persistence, based on bottom‐up and top‐down approaches. Knowledge gaps related to bacterial food safety hazards associated with persistence in the FFPE and priorities for future research are provided.

Unveiling the Mutations and Conservation of InlA in Listeria monocytogenes

“…Studies have shown that CC1 and CC2 are the most prevalent clones in clinical strains, whereas CC9 is often found in food and environmental samples and is a clone with low-virulence [ 19 ]. ST5 and ST121 are known to exhibit higher tolerance to adverse conditions and their capacity to adapt to such environments has been found to be crucial in the formation of biofilms, thereby affecting the persistence of L. monocytogenes in the environment [ 30 , 31 , 32 ].…”

Prevalence, serotype, antimicrobial susceptibility, contamination factors, and control methods of Salmonella spp. in retail fresh fruits and vegetables: A systematic review and meta‐analysis

“…Although previous reports suggested that conveyor belts, centrifugation, and filling operations are not typically significant sources of contamination (EFSA, 2014d). However, there have been reports proving that processing equipment has become an important source of microbial contamination in fruits and vegetables (EFSA, 2024;Snyder et al, 2024). For example, after centrifuging fresh fruits and vegetables, the total natural microbial community in the fruits and vegetables increased by about 1 log unit CFU/g, indicating that the surface of the processing equipment may be a source of microbial contamination and recontamination (EFSA, 2014d).…”