One of my extended family members is a great follower of food and medicine expiration dates. No sooner has the expiration date been crossed - even if it's only by one day - she gets so fearful that she wants to throw them away regardless of their condition. I've been telling her that it doesn't mean that the food or medicine will suddenly turn bad just because the expiration date has been crossed but she doesn't listen. Better to be on the safe side, she told me.
online article on Slate that sort of vindicated all of my beliefs. I would urge everyone to read it. Here's an excerpt from it:
The fact is that expiration dates mean very little. Food starts to deteriorate from the moment it's harvested, butchered, or processed, but the rate at which it spoils depends less on time than on the conditions under which it's stored. Moisture and warmth are especially detrimental. A package of ground meat, say, will stay fresher longer if placed near the coldest part of a refrigerator (below 40 degrees Fahrenheit), than next to the heat-emitting light bulb. Besides, as University of Minnesota food scientist Ted Labuza explained to me, expiration dates address quality—optimum freshness—rather than safety and are extremely conservative. To account for all manner of consumer, manufacturers imagine how the laziest people with the most undesirable kitchens might store and handle their food, then test their products based on these criteria.
The last sentence should be read and re-read until fully understood: "To account for all manner of consumer, manufacturers imagine how the laziest people with the most undesirable kitchens might store and handle their food, then test their products based on these criteria."