Strangely, my cat does this, but only people food ie cooked chicken. This would infer he comprehends that I am heating it til it gets hot. He doesn't paw kitty treats, dry food, or his canned food, or people food prepared away from the stove (ie yogurt). So he's touching to test it for heat. As a kitten, I placed his paw on a warm (not hot) burner, to keep him away (it worked). (No fears, he wasn't burned!)

Is it possible he's this smart, or is this a common cat behavior? He is smart: I just asked him if he wanted to sleep next to mommy, and he jumped from where he'd been curled up to the sofa and snuggled right up to me. Cats are amazing.