Listeria monocytogenes is a bacterium which can give rise to food poisoning and so is a serious food safety concern in food production.
In 2015 according to Public Health England, there were 169 cases of listeriosis in England and Wales. This might not sound many, but the mortality rate for this pathogen is high at approximately 30% of cases.
The elderly and unborn / newly-born babies are most vulnerable to the disease. Listeria monocytogenes is the only member of the genus Listeria which is recognised as a human food pathogen. However, all Listeria species have the same growth requirements, and so the presence of a ‘non-hazardous’ Listeria can be indicative of the presence of Listeria monocytogenes.
Listeria is found in the general environment and so can be associated with any food that is grown in association with the soil (e.g. salad leaves). This bacterium can:
These characteristics enable Listeria and Listeria monocytogenes to cross-contaminate foods that have undergone a process to eradicate vegetative pathogens (e.g. cooking), and so it can pose challenges to food manufacturers.
When monitoring for the presence of Listeria in a food production facility there are key areas to look at. Two of the most frequently contaminated are:
Cleaning equipment is often forgotten when considering how to maintain a Listeria-free production environment.
The Food & Drug Administration (FDA) has recently identified four zones of importance when controlling Listeria in RTE production facilities in the USA.
These of course are also of relevance to UK and EU operations:
Zone 1 Direct food contact surfaces in the plant (e.g. blenders, conveyors)
Zone 2 Non-food contact areas in the plant that are closely adjacent to product contact surfaces (e.g. framework of equipment, drip shields)
Zone 3 Non-food contact surfaces that are not close to food contact surfaces zone 1 (e.g. walls, drains) and zone 4) areas
Zone 4 Areas remote from the product processing areas (e.g. office areas, locker room)
Listeria monocytogenes is a very dangerous food borne pathogen. The 2017/2018 outbreak in South Africa, where there have been approximately 950 cases and 180 deaths is testament to that. While producers of ‘at risk’ products should be aware of problems associated with Listeria and better prepared with a knowledge of control measures, plant managers need to pass this information to their entire staff. With the right training and the proper controls, staff should understand how to identify Listeria problem areas, reduce the risk of listeriosis with hygiene practices, and control future outbreaks.
If you produce chilled, ready-to-eat foods, you’ll need to know where you have to clean to avoid food contamination. This post details the most common Listeria hideouts – and how to clean for this...
Find out what Global Food Safety Schemes, including BRC, FSSC 22000, and SQF, say about cleaning tool selection, use and maintenance requirements, and how you can optimise your cleaning tool audit...
Today, the best way to make your investment in Vikan profitable is to have a customised site survey carried out. In sectors with high hygiene requirements, such as food preparation environments...