The expiration dates on your groceries may mean less than you think.
This happens in my household all the time: I'll be cleaning out my fridge and see that eggs or yogurt or meat has expired. I'll sniff it and poke it, and it'll smell fine. But then images of salmonella flash through my head, and I toss it.
Apparently I'm not the only one doing this. Americans throw away 34 million tons of food per year, and a good amount of that is as a result of loyalty to the "use by" date. A professor quoted in this MSNBC article explains that we should take these dates with a grain of salt, and that "there's no magical threshold after which a certain food harvested on a certain date suddenly goes bad." (There are a few exceptions, like baby formula.) The factor that accounts for the range, he says, is how much the food has been handled before it reaches you.
Here's an idea: how about a label that functions as a timeline, that can give you an idea of what your food's been through? Certain prepared foods in grocery stores have "packaged on" dates; why not more processed foods? That way, we could institute a "use 3 weeks after packaging" stamp, that gives you a spectrum of freshness. It would save a whole lot of landfill space, not to mention precious grocery dollars.