How do I recognize whether a Gorgonzola has gone bad?
If it grows a grey or pink mold around the edges, or a black mold, throw it out. That's an undesirable mold. Those molds aren't usually dangerous, but they can make the cheese taste bad. With gorgonzola cheese specifically, the mold is injected in to the cheese via needle-like things, and then it grows veins from there. If a mold is a different color and it's coming from somewhere other than the veins, that is probably not a good mold. See also this question.
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