The presence of biofilms in food and beverage processing facilities pose significant risks to food safety. As well as causing spoilage, they also harbour and protect some of the main food pathogen bacterias such as Listeria, Salmonella and E. coli.
To ensure products are being made in the safest possible environment, a preventative approach to biofilms should be taken. However, if biofilms are detected on an equipment’s surface or in a pipe, it is important to take immediate action to decontaminate the area.
Preventing Biofilms
Cleaning and Disinfection
Effective, verified, and validated cleaning is critical. All phases of the cleaning process need to be followed at the recommended frequency to prevent the formation of biofilms. It is important to verify that hidden and enclosed food contact surfaces have been cleaned correctly and be aware that using high-pressure cleaning equipment carries the risk of distributing biofilms to other areas of the factory.
Good Hygienic Design and Maintenance
The EHEDG (European Hygienic Engineering and Design Group) recommends that all production equipment is designed and installed in such a way that it is cleanable.
It is also important to monitor the surrounding production environment and facilities to make sure they are in good order and well maintained. Welding, rust, cracked seals, and hard to reach places are all hotspots for biofilms and should be regularly inspected.
Detection Methods
The appropriate detection method will be determined by the type of product that is being produced and the area within the factory that is suspected to contain biofilm. These include:
- Staining
- Sampling and analysis
- Sensors and detectors
Removal Methods
When the presence of Biofilms is confirmed, there are two methods to use in an attempt to remove it: physical treatment and chemical treatment. It is important to note that if the right approach is not taken, it is extremely difficult to remove biofilm, as research cited in Corcoran et al1 (Nesse et al. and Russo et al.) indicates:
“Molecular typing has indicated that particular strains of Salmonella can persist for up to 10 years in food processing environments. Russo et al. recently reported that a Salmonella enterica subsp. enterica serovar Agona strain responsible for two food-borne outbreaks remained in the environment of a food processing facility for 10 years despite intensive cleaning and decommissioning of contaminated equipment”.
While poor sanitation methods and bacterial reduced susceptibility to the disinfectants used could be the cause, Corcoran et al suggest that a Salmonella biofilm should also be considered.
Physical Treatment
Scrubbing, scraping, mechanical spraying, pressure spraying, or internal pipe cleaning will be carried out depending on the situation of the biofilm.
In pharmaceutical plants, using heat treatments is commonplace.
Chemical Treatment
A selection from:
- Detergents/descaling agents (typically used on external surfaces and referred to as Open Plant Cleaning (OPC))
- Non-oxidising biocides (note that this will only treat the bacteria and cannot penetrate and remove the biofilm)
- Oxidising biocides (typically more effective than non-oxidising biocides)
Are your Control Programs Effective?
Diversey SecureCheck can help you identify the areas within your processes that have the potential to harbour and promote the spread of microorganisms and will help you define preventative control measures.
Learn more about Biofilms
The Biofilm Management in Food and Beverage Processing online training module from the Diversey Hygiene Academy will increase your knowledge and understanding of Biofilms, how to correctly identify them, prevent them and implement corrective actions if required. The course can be provided via our learning management platform on a company, site, or individual basis.
