Chances are, you've probably taken a bite of something in the fridge that's just a teeny bit past the expiration date, in an effort to see if it's safe to eat the rest of it. If it's gone dangerously bad, it should taste yucky, right? Not necessarily.
According to the U.S. Department of Agriculture, there are two different types of bacteria that get on and into your food. The first, which are called spoilage bacteria, can grow at low temperatures, even in the refrigerator, and they make the food look and smell bad enough that you won't want to eat it. Oddly, though, these germs usually don't cause illness.
The ones you have to worry about are pathogenic bacteria, which typically don't alter the taste, smell or appearance of food [source: Zeratsky ]. And it only takes a tiny amount of bacteria or another pathogen to make you seriously ill. Instead of a taste test, it's far safer to follow expiration dates on packages, and the federal government's safe storage times for the refrigerator and freezer, which you can find at Foodsafety.gov.