It is important to sample surfaces of processing areas, equipment and processing aids (such as compressed air, brine solutions, drain water) because foods can be contaminated during processing by pathogenic bacteria that persist in the manufacturing environment, e.g. various species of Listeria and Salmonella. Our wide array of pathogen detection products is designed to provide you with easy surface sample processing solutions that detect and enumerate these pathogens, and ultimately enable you to implement corrective actions to prevent bacterial contamination of processed foods.
The hygienic status of a given surface can contribute directly to the risk of an adverse outcome in product safety/spoilage (food), batch failure (pharma) or nosocomial infection (healthcare). The degree of attendant risk will be defined by the terminal process designed to reduce it, i.e. sanitizing of food contact surfaces, sterilization of surgical instruments and control of airborne contamination.
Microbial Contamination on surfaces
Microbial contamination of surfaces is assessed directly by culture of the microorganisms or indirectly by verification of cleaning and disinfection procedures designed to prevent microbial proliferation. Results from surface hygiene assessments are either traditional growth-based data (direct) or ATP, NAD and residual protein data (indirect). Data generated by traditional culture techniques usually include a total count, entero count and E. coli as an indicator. Specific pathogens may also be assessed.
Samples are collected according to a sampling plan by:
Adenosine triphosphate (ATP) techniques provide data in real time. Whilst a small proportion of the signal generated is from microbial ATP, the techniques are not microbiological. The principal of the test is to highlight where there has been a failure of the cleaning and disinfection procedures designed to minimize the microbial impact on products/patients.
Samples from surfaces are collected by swabs moistened with extractant that releases the ATP from any intact cells, usually from product residue. The released ATP drives the enzymatic conversion of luciferin to oxyluciferin. The reaction produces a photon of light for each molecule of ATP consumed. Therefore, the amount of light produced is proportional to the amount of ATP present. Results are expressed in Relative light units (RLU) and the bigger the number the more ATP was present in the sample resulting from elevated levels of product residue on the surface tested.
An ATP test will not directly detect the presence of viral particles, however it can be used to give a quantifiable indication of cleaning effectiveness and adequate removal of environmental proteins, even if viruses like SARS-CoV-2 are not directly detected.
DKSH offers a comprehensive range of effective active microbial air monitoring solutions for use in the food and beverages industries, where regulations are on the rise and standards become ever more stringent. Because the hygiene standard in a production environment is directly linked to the microbiological safety of the finished products, we make sure that our active microbial air sampling solutions generate highly precise, reliable and reproducible results. Air monitoring systems also fully comply with international standards and regulations – for your convenience and safety. Our range includes air samplers that use settle plates or contact plates.