I found this article and I thought it was interesting, so I wanted to share! The entire article is several pages long, so I'm just going to post the link and part of it.
Do Food Expiration Dates Really Matter?Experts provide a guide to the variety of confusing 'freshness' dates on food.Reviewed by Brunilda Nazario, MD
You open the fridge, drag out the cottage cheese, check for fur, and if there isn't any, you say, "Honey? Will you sniff this?" This is not, however, the approved method of checking for freshness. The approved way lies in a voluntary system of labeling.
Yes, voluntary. The only items required by federal law to be labeled for expiration are infant formula and some baby foods; some states also mandate pulling dairy from store shelves on the expiration date.