Slime, also known as yeast, mold, biofilm, organic growth, and biological pollution, can come in all different color, shapes and sizes.

The precursors to slime are naturally occurring in the air and are typically introduced into ice machines and other foodservice equipment as the natural operation of the equipment draws in air.

Once in contact with the food equipment surfaces, slime takes hold and begins to proliferate.

If left untreated, slime can quickly expand and cause loss of performance, decreased efficiency, equipment fouling, malfunction, and even complete contamination.

To illustrate what this concept means inside of an ice machine, understand that micro-contaminants such as bacteria and fungus can grow at alarmingly fast rates. 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!

Ice machine cleaning and maintenance to regularly remove slime can easily cost operator more over the lifetime of the equipment than the cost of the equipment itself.

Bacteria/Viruses known to contaminate ice cubes:

  • Cholera
  • Typhoid fever
  • Salmonella
  • Legionella
  • E. coli
  • Shigella
  • Mycobacterium
  • Hepatitis A
  • Norovirus

How Bad Can Slime in an Ice Machine Be?

Here’s an image of an ice machine contaminated with mold, slime, bacteria and biofilm:

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Slime Isn’t the Only Problem Growing Inside of Ice Machines

There are numerous published reports of infection outbreaks that have been traced back directly to contaminated ice machines.

Peer Review Journal Articles on Contaminated Ice Machines:

  • Clin Infect Dis.-2002-Gebo-32-8
    Describes Mycobacterium fortuitum infection spread across patients and the source was traced back to a contaminated ice machines.
  • Nosocomial Mycobacterium gordonae pseudoinfec.. Infection Control
    Describes a 16X increase in the contamination rate of clinical laboratory specimens. Extensive hospital-wide cultures of water sources implicated the use of ice and ice water from contaminated ice machines as the source.
  • Appl. Environ. Microbiol.-2009-Williams-2091-8
    Describes biofilm (bacteria) formation and how ice machines in particular are potentially problematic and calls for adequate ice machine maintenance to prevent infection in healthcare settings.
  • Infection Control and Hospital Epidemiology May 2009 Vol 30 No 5
    Describes a contaminated ice machine at a hospital that was exposing patients to Legionella pneumophila, which is the primary human pathogenic bacterium that causes Legionnaires’ disease (legionellosis). The ice machine had not been serviced in years and the upstream water filters had never been replaced. This paper emphasizes how important sanitized and maintained equipment is (i.e., ice machine and bin).
  • Appl. Environ. Microbiol.-1999-Covert-2492-6
    Describes that Nontuberculous mycobacteria (NTM) are a major cause of opportunistic infection in immunocompromised hosts. In this study the widespread occurrence of NTM was examined in drinking water, bottled water, and ice samples. NTM were not detected in bottled water or cisterns but were detected in 54% of the ice samples.

There have been several news stories documenting studies conducted in restaurants that reveal that ice machines face serious hygiene challenges for operators.

In fact, several studies have demonstrated that samples of water taken from a restaurant’s toilet have fewer bacteria than samples of ice from the same restaurant.

News Articles on Contaminated Ice Machines:

Ice machines and other common foodservice equipment provide the ideal environment for biological pollution not only to survive but to THRIVE.

IceZone® creates an environment inside of the ice machine and ice bin that inhibits the growth of organic contamination. Find out more about IceZone, THE SOLUTION to prevent mold, slime, yeast, bacteria, and other organic growth in ice machines and more!



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