Screwdrivers are designed with the intent to do one thing well: Drive screws, but the designers’ intent doesn’t stop screwdrivers from being used poorly as chisels, pry bars, door knobs, fondue forks, lawn darts, etc., etc. Likewise, ATP (adenosine triphosphate) sanitation monitoring systems are designed to do one thing extremely well: Detect and measure ATP on surfaces and in liquids as a method of determining the relative cleanliness of the surface or liquid. But the designers’ intent doesn’t stop ATP sanitation monitoring systems from being used poorly as methods of determining a food sample’s total microbial plate count, or detecting an unlabeled food allergen before it can contaminate a non-allergenic food.
Explore this issueAugust/September 2006
“I spend a great deal of time working with food safety professionals to help them understand what ATP sanitation monitoring systems can do for their operations, and then assisting them to implement the systems into their facilities,” says Jim Topper of Neogen Corp. (Lansing, Mich.) “Properly utilized, sanitation monitoring systems allow for the almost instantaneous detection and measurement of ATP on food contact surfaces, which provides an objective, actionable tool for monitoring of a facility’s sanitation efforts.
“ATP systems provide immediate feedback on whether a facility’s sanitation efforts have been thorough enough to prevent the accidental contamination of its products with residues from previous production runs, or the microorganisms that they may harbor,” Topper continues. “The potential consequences of shipping contaminated product are well documented. But as obvious as the advantages of using an ATP detection system seem to be, I routinely spend a lot of time with food safety professionals to help them understand what ATP detection systems cannot do well.”
What ATP Sanitation Monitoring Systems Detect
ATP is the energy source in all living cells. Since virtually all of the food and beverages produced were once living, they contain ATP. Microbiological organisms, like bacteria, yeast and mold, also contain ATP. As a mixture of food, beverage, and microbiological material comes into contact with pipes, tanks, and food and beverage production surfaces, it leaves its ATP on whatever it comes into contact with.
In very simple terms, ATP sanitation monitoring systems detect the amount of organic matter that remains on food contact surfaces, in liquids, or on pipes, tanks, etc., after a company has completed its sanitation efforts. The amount of ATP detected, and where this ATP was detected, signals company personnel of possible trouble spots that may need to be resanitized prior to the start of the production cycle. Simply detecting excessive amounts of ATP, however, does little to definitively identify the source of the ATP. ATP sanitation monitoring systems are not designed to differentiate between the various sources of ATP.
“The more ATP that is present on the sampling pad when it interacts with the reagents in the sampling device, the more light that is created, and the higher the reading that the system’s luminometer will return. It’s that simple,” Topper says. “But, to the reagents universally used by such systems, ATP is ATP. Period!”
ATP sanitation monitoring systems are easy and quick gauges of a facility’s cleanliness, which are easily customized for the specific equipment, people, product, and processes used in any food production facility. The systems set an objective, recordable, and traceable standard to help avoid the consequences of substandard sanitation efforts.
ATP Results Do Not Correlate with Microbial Counts
It is a common misconception that the results received from ATP testing systems in relative light units (RLUs) for surface samples, for example, should in some way correlate with a microbial total plate count result for the same samples.
“Some of those I work with would like these ATP systems to be more specific, but they are not. They are strictly about telling us how well we’ve cleaned,” Topper says. “You could have an extremely high RLU reading that, in fact, detected the ATP from very few microbes. Inherent in our cleaning process is the need to minimize the risk of microbial growth and cross-contamination. That’s why we clean.