Owning and operating a properly maintained and sanitized ice machine can seem like a chore.

Following the manufacturer’s recommended cleaning schedule can be time-consuming, costly, and (for some) hard to remember.

The consequences, however, of improperly maintaining an ice machine can be disastrous.

But when most people think of ice machines they think of cold, after all, ice machine creates and store frozen liquid.

They must be cold, right? And how bad could a cold environment get? Bacteria, mold, and other contaminants cannot grow in the cold, right? Right???

The Truth About Ice Machines

Of course there are parts of an ice machine that are held at temperatures at freezing or below, but unfortunately, this isn’t the case for the entire machine.

There are parts of an ice machine that are moist, warm, and dark; in other words, the perfect breeding ground for micro-contaminants like bacteria and fungus.

Slime in Ice Machines

There is a name for the unpleasant substance that forms inside of ice machines, slime. Slime can be composed of yeast, mold, biofilm, organic growth, biological pollution or a combination of one or more.

Color (black slime is shown in the adjacent photo), shape, and size all vary based on what makes up the particular colony of slime.

The formation of slime is inevitable in ice machines in most environments because everything slime needs to proliferate is present under normal operating conditions.

Slime in ice machines is formed when even a single colony forming unit of contamination in the air is drawn into the machine during the normal ice-making operation.

Once inside micro-contaminates find the perfect breeding ground waiting for them. With temperatures between 41° and 145°F and plenty of moisture, micro-contaminants can thrive within an ice machine.

There is plenty of nourishment for these nasty critters as well, as yeast, food particles and other compounds in the air offer thriving slime colonies a steady diet.

In fact, several species of bacteria can expand at geometric growth rates, doubling in population size every 10 minutes.

That means that a singular bacterium left undisturbed on the food contact surface of an ice machine can grow in a single day into 22,300,745,198,530,600,000,000,000,000,000,000,000,000,000 bacteria!

Fighting Back

Following the manufacturer’s suggested sanitization schedule of annual or semi-annual deep cleanings is typically not adequate in most environments.

More frequent and more costly cleanings and sanitizing can help fight against the buildup of slime in ice machines.

However, as mentioned above, this can be difficult. Luckily there is an easier way.


IceZone® is a multi-patented Clean-In-Place (CIP) food equipment sanitation system that prevents slime, mold, bacteria, viruses, fungi, and yeast from growing on the surfaces of ice machines.

It has been proven by independent third-party test labs to eliminate over 99% of surface micro-contamination.

IceZone Subway Case Study: IceZone Saves Restaurant Operator Millions


Biozone Scientific designs and manufactures ultraviolet light commercial and industrial applications, creating systems for virus disinfection and sanitation, preventative maintenance, and odor control solutions.

Headquartered in Orlando, Florida, we serve clients globally, with offices in 5 countries on 3 continents.


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+44 (0)7399 200589
+44 (0)7399 200589

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