Like most people, you probably reach around to the back of the market's dairy case for the freshest milk, and sort through the meat packages to pick the pork chops with the latest date.
She has worked the meat and poultry hotline for the United States Department of Agriculture for 11 years.
With just a couple of exceptions, no laws regulate package dates -- variously referred to as sell-by dates, pull dates, expiration dates or quality dates.
That most dates appear at all is entirely up to the manufacturer or the grocer.
It is strictly industry practices." Many perishable products such as milk have conservative dates, which means that they are expected to stay fresh for at least a week after the imprinted date.
And shelf-stable products like cereal or pasta that bear "best if used by" dates will stay edible for months beyond the date. "In the United States, we're just very comfortable with numbers," says Carl Winter, food toxicologist at the University of California at Davis.