For a person who works at a breakfast site, I have a fairly contentious relationship with breakfast. It's a lovely meal, sure, sure, but it's also one that I've never totally figure out how to eat in a reasonable way. When I wake up, I'm not hungry or patient enough to do anything but down a cup of coffee and go to work. On some rare occasions, I will grab a banana and eat it on my walk to the subway. Most mornings, I bring a cup of Greek yogurt to eat at my desk. But mornings are busy, and I've never been that hungry before noon, so it usually takes me at least an hour and sometimes two to get through the whole cup of yogurt. I keep forgetting about it, and so it sits there, open, until roughly 11:30. And so it is with some nervousness in the pit of my stomach that I set out to answer the question: How long can you keep yogurt outside of the fridge? I mean yogurt is already full of bacteria, right?
Turns out, ha, not so much. According to the US Department of Health & Human Services, you should throw out yogurt if it's been out at room temperature for more than two hours. If the temperature is higher than 90 degrees Fahrenheit, you only have one hour to eat that yogurt sitting out of the refrigerator. Granted, our office is usually below the 90 degree threshold, but turns out that leaving a yogurt unopened to slowly eat from is not a great idea from a food safety standpoint.
That said, I'm not the only person who thinks that the two hour-guideline is excessively conservative. (Surely I'm not the only one who brings a cup of yogurt into work without a second thought, right?) Anecdotally, I don't think I've ever gotten sick from leaving a yogurt out an extra hour. But to be fair, signs that your yogurt has spoiled aren't always that obvious. One tell-tale sign is that yogurt sours—but plain Greek yogurt is already sour, so I wonder if I would even notice? Another, more surefire sign that your yogurt has spoiled is discoloration or moldy spots. Those, for sure avoid. And in the long run, it's probably worth chucking your yogurt to avoid food-borne illness than to save a few dollars.