Processing Environment Monitoring in Low Moisture Food Production Facilities. Are we looking for the right microorganisms?


Prevalence of pathogens of concerns for Low Moisture Foods (LMF) is considered through investigation of the reported foodborne outbreaks.

A Processing Environment Monitory programme (PEM) needs to be in place in order to identify points which need to be routinely sampled, search for harbourage niches, and detect and destroy pathogens of concern. These programmes need to be specifically designed considering the specific pathogens and production set up.

However, a monitoring programme on its own is not sufficient and needs to be accompanied by corrective and preventive action plans to ensure efficient application of the Good Hygiene Practices.

A tool for both food producers and regulators

This guidance document is intended to help set up targeted processing environment monitoring programs depending on their purpose, and therefore provide the essential elements needed to improve food safety.

Several food pathogens are of significant concern when planning monitoring programmes for LMF, and are discussed in this document:

  • Salmonella,
  • Cronobacter spp. (posing risk to infants),
  • pathogenic E. coli,
  • B cereus
  • Listeria monocytogenes.
Table 2 from Processing Environment Monitoring in Low Moisture Food Production Facilities. Are we looking for the right microorganisms?

Overview of recalls, withdrawals and safety alerts with microbial pathogens in the EU and US in 2012-2017. EU data were extracted from RASFF (2020) and US data were extracted from FDA (2020).

There is a great interest in the food industry to perform validations in a manner that would be accepted by all parties involved, for example, authorities and customers.

Low moisture foods are foods that:

  • are naturally very low in moisture,
  • have had water removed from them,
  • have a higher moisture content, but that contain agents that prevent the moisture from being available to microorganisms to allow their growth.

In this work, the "production environment" includes production equipment, production surfaces, floors/walls/ceilings, and the air within the production area.

Low Moisture Foods are defined as having a water activity of
or below.
In the EU and USA there were
combined alerts for microbial pathogens and LMF.
Between 2010 and 2017, EFSA reported
salmonellosis outbreaks from LMF alone.

Genetic characterization of isolates provides interesting insights for understanding the difference between resident and sporadic strains in a processing environment.