Can you smell it? Does the very mention of the word conjure up a memory bank full of tasteful experiences? If you can't smell it I suggest you stop what your doing right now, including reading this, walk over to the fridge, pull out the green tube (regardless of brand, it's always a universally recognizable green), open it up, and take a good whiff. The verb smell doesn't really connote what we do with a cheese. Whiff is much more descriptive of the act. Then take another moment to smell it, more than just a whiff. Inhale it. Feel the deep aroma of the Parmesan enter your nose and travel into your lungs. If you really focus, you'll feel the smell make itself at home there. Take another deep breath and pay attention as the pungency circles around and curls up like a kitten in your chest.
Is it a good smell? Does it remind you of pasta or a golden brown breast of chicken parmesan, crusted to perfection? You've craved it before, haven't you? Wasn't there a time when the spaghetti just didn't seem too great because the parmesan cheese was missing? It is a good smell.
Now imagine opening an expired carton of milk and taking a whiff (it really is a whiff, isn't it?). Imagine smelling that same parmesan smell emanating from the milk carton ; it makes you want to throw up. Same smell, different context.
Not something you want on your Fruit Loops.