Ah, a perfect wedge of Bleu Mont Dairy bandaged Cheddar, fresh-cut and fabulous. Ideally, every cheese you buy is in such pristine condition. But then there’s real life. Remember that cheese that tasted a little stale, a little cardboardy? Maybe a little bit like the plastic it was wrapped in? Pat Polowsky, a graduate student in food science at the University of Vermont, helped me understand how easily cheese goes rancid atretail. And what can be done about it.