Black olives are an essential part of a kitchen pantry because they are so versatile. They can easily be tossed into a salad, chopped with garlic to make a tapenade or mixed with feta and mint to add a Mediterranean zest to any meal. Occasionally, we forget about our black olives and then comes the time to decide: to eat or not to eat?
Check the expiration date on the olive can or container. If the expiration date has already passed, the black olives could be bad.
Smell the olives. If they do not have a smell or they smell metallic or unpleasant in some way, they are probably bad and should be thrown out.
Examine the olives. If black olives have white fuzz on them, seem overly greasy and slimy or look patchy and discolored, they are bad.