Remove and Kill Biofilms in Food Plants

Remove and Kill Biofilms in Food Plants using industrial steam cleaners. Sometimes simplicity is the key to successful sanitation programs. And there is really nothing simpler than:

WATER + HEAT = STEAM.

But when you add the equation:

STEAM + PRESSURE = DRY STEAM,

You achieve pathogen-killing temperatures, pressure to assist in biofilms slime removal, and near zero moisture (5%)

But first, here is a brief explanation about biofilm, and why it is such a problem in food processing environments, and why conventional cleaning methods fall short (besides their environmental and monetary cost.):

Biofilms are a multitude of micro-organisms which adhere together on a surface, bound together by EPS (extracellular polymeric substance) or slime. According to Richard Lawley, writing on the website Food Safety Watch “The end result is a mixed microbial community that is much more resistant to environmental stress than free-living microbes or a single species biofilm. Importantly, these mixed species biofilms are also much more resistant to antimicrobials and sanitizers than free-living cells - one reason why they are so difficult to remove or inactivate.

… some bacterial species that are very important in food microbiology are known to have a propensity to form biofilms. First among these is the pathogen Listeria monocytogenes, a species that is known to colonize wet environments and one which is notoriously difficult to eradicate from food processing environments once established. Listeria has been shown to survive and grow in multi-species biofilms and can form biofilms on many of the materials used in food factories.

Pseudomonas spp. too are often found in biofilms and produce large amounts of EPS. These important food spoilage bacteria have also been shown to form films on stainless steel and other food contact materials and to survive in multi-species biofilms with foodborne pathogens like Listeria. Heat resistant Bacillus spp. and Salmonella are other important food-related bacteria known to attach to surfaces and to form biofilms.

A further feature of biofilms that is often overlooked is the difficulty of detecting them when they are present. Most environmental monitoring techniques depend on using a swab, or sponge, to remove bacteria and soil from a surface before using conventional culture methods, or ATP assay, to determine the degree of contamination. Unfortunately, swabbing doesn't necessarily remove an established biofilm completely, especially if it has formed on a rough surface. This means that the sample could be unrepresentative and give a misleadingly satisfactory result, when, in fact, contamination levels are unacceptably high."

So, biofilms can proliferate, in almost any environment, and can be hard to detect, as well as clean, especially in rough and hard to reach surfaces. Want to read something more alarming? They are exceedingly hard to kill.

As John Sofos Ph.D. points out in Sanitation: Biofilms our Constant Enemies: "Bacterial cells in biofilms may be as much as 500 times more resistant to sanitizing chemicals than free-flowing or suspended cells (planktonic) of the same species. Studies have found that sanitizer concentrations and exposure times may have to be increased 10- to 100-fold to be effective against cells in biofilms compared with interventions found to be effective against planktonic cells."

However, there is an eco-sustainable solution: Industrial Steam Cleaners.


In a study by the University of California at Davis, the most reliable method of sanitizing equipment and controlling pathogenic bacteria is with heat:

Heat may be applied using hot water or steam. Heated water delivered to the cleaning site via hose or pressure washer is dangerous because the water amounts and pressure produce an aerosol effect.

Also, standing water invites the growth of l. monocytogenes as well as other harmful bacteria, not to mention safety concerns. For these reasons, dry steam vapor is the optimal method for delivering pathogen killing heat.

Also, Industrial steam cleaners have the innate ability to penetrate nooks and crannies, so called niche areas by the FDA, and aforementioned rough areas. Also, many manufacturers, like AmeriVap Systems provide proprietary tools that make the job even easier and more thorough. This, with the positive side effect of using no chemicals as well as reducing water consumption and waste water levels, make the industrial steam cleaner a very compelling piece of equipment for any forward thinking company. For another good article on biofilms and their removal click here.


For information on biofilm and sanitizing floor drains click here.

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