If your sense of smell is out of order, and the food doesn't look bad, is there a test of finding out if it's bad?

Of course if in doubt throw it out, is a given. But if you just arrived in a city where you don’t know anyone to ask to smell the food you carried with you, (a huge amount of expensive food) what is the alternative to throwing it out? Is there some way of testing it? As in If you add something to it (or you put a small amount of it in something), if turns (or doesn’t) dot dot dot, it means dot dot dot