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Ask A Health Inspector: Let's Talk Mold

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Q: Hello Jason. Well, I have a question… I remember taking my kids out for Halloween trick or treating. They would come home with mountains of candy and being the good parent I was, I had to go through and pull out the “moldy” pieces of candy for quality control. I’m sure I saved my kids from all kinds of sickness. I recently read a couple of health inspections and noticed that many of them said “Ice machine in need of cleaning to remove the visible accumulation of mold and mildew.” This kind of mold actually sounds pretty scary. In the spirit of Halloween, I was hoping you could tell me why this mold and slime is such a big deal.

          -Keith M.

A: Happy Halloween Keith! Great question. I remember when I was a kid growing up in the 80s, after my mom bought my brothers and me a costume, you know, one of those old 80s costumes with the one piece outfit and plastic mask?  When you were at the store shopping for them, you could look in the box and see that plastic mask through the cellophane window? Smurfs, Transformers, He-Man, Magnum PI… those kinds of things? Anyway, Halloween would finally arrive and we would get our costumes on and my dad would drive us around to all of the houses. We had to drive because we didn't live close enough to any neighbors to walk. It was a big deal to get three kids out of the car, make sure our costumes were right, and get to the door. Of course, there was certainly no surprise when we knocked on the doors of the neighbors because we’d been there for twenty minutes before walking up to the house! But still, that didn’t stop my dad from loading us all up after we got our Mary Janes, sugar daddies, maybe a Twix, and those inevitable (and awful) peanut butter things wrapped in orange or black paper, and heading out for the 4-minute drive to the next house. Yep, Halloween was a special time for my family and me in the 80s, and we still love it. But now, on to your question… 

Slime. Mold. Mildew. These words evoke thoughts of an oozing mass of green, pink, black, or red ectoplasm, especially when talking about an ice machine, where it is usually seen. Makes sense though, ice machines are full of water and humidity, which is the perfect environment for the growth of moldiness. Now, is all mold harmful? Heck no! Penicillin comes from mold! Bleu Cheese comes from a molding process! And fermentation is kind of like controlling a molding process, and we all know what that leads to…Of course! Kimchi!

So if mold makes good things like fermented foods and tangy cheeses, why is it such a big deal in an ice machine? Why do I care? I care because the 2009 FDA Food Code defines ice as a food. 

Picture, in your mind's eye, a big green Jell-O mold in the shape of Slimer from Ghostbusters, with some tasty raisins inside. Well, in an ice machine, a biofilm (layer of mold and mildew) can form. This biofilm can harbor pathogens like Listeria, E. coli, and Salmonella. Just like Slimer is protecting those raisins, this biofilm provides some protection for those pathogens, and allows them to grow and multiply. To safely remove the offending biofilm, a process similar to the ghostbusting practice of using a proton pack and Ecto Containment Unit must be employed. The inside of the ice machine must be scrubbed and cleaned with a sanitizer that stops the growth of mold and wiped down again to safely eliminate the biofilm and loose bits of mold. 

Because we live in a time and place where we don’t really have to worry about how safe our drinking water is, we tend to believe that something as ubiquitous as ice is safe and clean. So how do those pathogens get into the ice machine anyway? Well, if you are a reader of my articles, you know that people don’t always wash their hands when they should. Food Employees in restaurants often handle raw proteins, and inevitably, some amount of pathogenic contamination is going to occur. Think about how ice is used in restaurants. Ice is used to cool foods in ice baths, or by simply adding ice to a food product. Sometimes bottles or cans are placed in ice to keep them cold. That’s a lot of back and forth trips to the ice machine with scoops and hands plunging into mounds of shiny, cold ice. Take a look at any meat market and you'll see raw proteins sitting on top of ice. Easy to see how pathogens could make the jump there. 

Now that we've talked about some of the biological hazards associated with ice machines, let's talk about physical hazards.  In the same way that pathogens can jump from bare hands into an ice machine, think about chunks of food that might be stuck on a food employees hands. Could be a small piece of diced onion or a sticky piece of raw chicken. Sometimes pieces of mold fall into the ice, sometimes screws fall into the ice, sometimes people put their leftover sardine sandwich in the ice machine to keep it cold.   

My point is, during your quality control efforts, be sure to keep an eye open for things in food that are not supposed to be there. You might be able to spot a bolt in your cherry coke, but you aren't going to see Salmonella or E. coli which can grow in ice machines. Spooky stuff! So, who ya gonna call if you have concerns about food-borne illness? The local health department! And, remember that if you do, you’ll need to report EVERYTHING you ate, including beverages.

Stay cool, friends, and have a great Halloween!


by Jason Masters, REHS

Environmental Health Specialist