Is there any reason to worry about sliced melon (watermelon, honeydew, cantaloupe)? Food safety with cut melons is not something that the average person thinks about (it’s a fruit, not chicken, right?), but understanding how they’re able to make you sick is something that you shouldn’t miss.
So why is cut melon a risky food?
It starts where we grow the melons. Most melons are grown on the ground. Not a problem, right?
Well, yes and no. The ground is dirty – being made of dirt, obviously – but the rind protects the inside of the melon (the “meat”). The problem is that germs like E-coli (E-coli 0157:H7) can sometimes hang out on that rind.
How do the germs get there?
The E-coli bacteria that we worry about come from cows’ fecal matter (cow poop). Some farmers use it (giving it the slightly fancier name of manure) to fertilize their crops. In addition, there are no outhouses for cows; they walk around in fields answering the call of nature wherever they please.
The E-coli may be there, or it may not be; we don’t know. However, because scientists learn from previous mistakes, we do know that some melons have E-coli floating around on the outside of the melon.
How does it get inside the melon?
In most cases, the E-coli germs don’t do too much to the rind of the melon. It’s the cutting of the melon that can cause the problem. If you don’t properly wash the melon before you cut it, you might introduce E-coli to the inside (the meat). Once there, the germs find enough nutrients to grow on, all they need is the proper temperature and time to grow.
Let the melon slices sit on the table at your backyard BBQ, or in the kitchen waiting to be served, and give them enough time in the Temperature Danger Zone (41 ˚ F to 135 ˚ F; 5 ˚ C to 57.2 ˚ C) and the germs start to reproduce. Since it is very rare that anyone cooks melon, the E-coli will be consumed by you when the melon is! ( To learn more about how food borne illness starts and spreads, click here.)
So how should I keep cut melons safe to eat?
Wash your melons and your other produce completely (we’ve done a whole page on washing produce; click here). This will help you remove any germs from the outside before you start cutting. Although using water to scrub the melon rinds isn’t bad, there is reasonable evidence that using vegetable washes will also help (we’ve linked to a video here).
Make sure that the knives and cutting boards you use are also clean. And – oh yes – wash your hands before doing the cutting! (Why? Click here.) Then place the cut melon in the refrigerator or an ice chest to keep it cold; this will prevent any germs that escaped the cleaning from growing too quickly.
When should I throw it out?
Always keep cut melons COLD. If melon pieces sit out at room temperature for longer than two hours, trash them. If you have to wonder how long they’ve been out there, they’ve been out too long.
Cantaloupes, honeydews and watermelons, among other types of melons, are great, nutritious foods - but if they're handled incorrectly, they can make you very sick!