Who doesn’t love an afternoon out in the sun eating good food at a picnic? Most people do and unfortunately, so do most bacteria. If you’re outside enjoying a picnic, odds are that you’ve got a container of potato salad sitting out in the sun. And that could mean trouble.
Potato salad is notorious for going bad and cultivating bacteria that cause foodborne illness. But what is it about potato salad that makes it a potential danger? My instinct is to point a finger at the mayonnaise. After all, it is made with raw eggs. That’s got to count for something, right? Well, maybe not. While it’s true that commercialized mayonnaise is made with uncooked eggs, those eggs are pasteurized and are free from dangerous bacteria like salmonella. Mayonnaise is also made with vinegar and lemon juice, which creates an environment that is too acidic for bacterial growth. In fact, mayonnaise doesn’t need to be refrigerated at all because it’s so acidic (though storing it in the fridge does help maintain its flavor and consistency).
So, if it’s not the mayonnaise cultivating bad bacteria, then what is it? The chief culprit for foodborne illness is actually (drum roll, please . . .) the potatoes! Baked potatoes are a TCS food, which means that they need “time/temperature control for safety.” If left for too long in the Temperature Danger Zone (between 41° and 135° Fahrenheit), baked potatoes can cultivate enough bacteria to cause foodborne illness. Potato salad should not be left out at room temperature for longer than two hours, as that’s how long it takes for bacteria in TCS foods to multiply to dangerous levels. Additionally, when the temperature is above 90° Fahrenheit, the U.S. Food Safety and Inspection Service recommend cutting those two hours down to just one. If you know your picnic will last longer than two hours—or just one hour on a hot day—play it safe by bringing a cooler to refrigerate your potato salad, or be prepared to throw out the leftovers.
Potato salad can be a tasty and harmless addition to your picnic, just as long as it’s prepared safely and kept under time/temperature control. By following these safe food practices, you can have your picnic potato salad and eat it too.
- Suzanna Davis