You might think that the worst you can find down the back, in or around a refrigeration unit would be a bit of ancient cheese, pushed out of sight by an enterprising toddler. Well, we’re not ruling out the cheese, but we’ve got some news for you: the worst that lives in those hard-to-reach spaces is more than enough to put your customers off their morning coffee.
Meet the biofilms.Here’s where they come to life: in the sort of dark, damp spaces where bacteria thrive. Once a few bacteria have adhered to a surface, they begin to multiply, and different kinds are attracted to the same spot through a form of bacterial communication called ‘quorum sensing’. As the bacteria form a colony, they begin to secrete a robust, jelly-like substance called a biofilm. As the colony begins to mature, the biofilms thicken and the bacteria start to disperse, covering more surfaces and spreading as far as they can.
Bacterial colonies will produce biofilms in any damp, humid environment – anywhere from the drains in your shower to the bottom of your fish tank to the spaces between your teeth (we call this dental plaque!). But refrigerators – especially the large, industrial models in supermarkets – are a particular favourite. And that’s a problem, if you’re the manager of a large grocer. Not only do biofilms look unsightly and unhygienic, but they can lead to food contamination, total equipment breakdown and a fatal loss of consumer confidence.
Want to know how? Here’s a common timelinefor biofilm mayhem:
Bacteria are transported by the airflow and introduced to refrigerator ->
The biofilms begin to plug the water drain in the refrigerator. ->
The water, instead of draining, backs up. ->
The water comes into contact with the fan motors, short-circuiting the motors and corroding the outer casing. ->
The now-limited air-flow forces the fridge to drop its internal operating temperature. ->
Ice forms on the coil and begins to freeze in the water tray, causing more blockages and internal damage. ->
Water begins to spill out onto the shop floor, presenting an immediate hazard for customers. ->
An engineer is called, and the unit is demerchandised and switched off. ->
Sales revenues are lost and, after prolonged or repeated shut-down, so is consumer confidence.
And all this can reoccur in as little as four to eight weeks.