Are Expired Foods Still Safe to Eat?

When it comes to expiration dates, food safety and food quality comprise vastly different criteria. Surprisingly, long-expired food is still considered — by the regulators, at least — good enough to eat. That outdated granola bar packed with soft oats or that chocolate bar now displaying a whitish bloom may not taste very good, but they can still be consumed without making you sick.

In fact, the expiration dates on your food don't have much to do with the risk of food poisoning. For example, you could buy a package of raw chicken and neglect to refrigerate it. The chicken could become bacteria-ridden within a few hours and become unsafe to eat — no matter what the expiration date on the package says.

These dates are evidence of an inconsistent and outmoded system initially implemented as a way to address consumer concerns about food freshness. By the 1970s, consumers weren't getting their foods from a backyard garden or neighboring farm but from the market, where foods were often sold past their prime. More than 10 congressional bills were introduced from 1973 to 1975, all with a food-dating focus. The result was the patchwork of federal and state food dating regulations that are still confusing consumers today [source: Sifferlin].

In the absence of sweeping national rules governing food dating, state governments have filled the gap. Forty-one states have implemented food-dating rules with little consistency. For example, one state regulation may not allow a box of crackers to be sold after its stamped date while another state may not require an expiration date at all [source: Sifferlin].

Food scientists determine expiration dates based on observing how long it takes for a food to start losing its quality (change texture, lose flavor and so on) under proper storage conditions. As we said earlier, this doesn't mean it is unsafe to eat. It just may not look its best. For highly perishable items like ready-to-eat salads, scientists also look at how much microbial activity is present after a certain number of days, since harmful bacteria could be present before a person could detect spoilage [source: NSW Food Authority].

In general, if you have purchased a perishable food item before its expiration date and promptly refrigerate it, it will keep for quite some time. Eggs, for example, can be used up to five weeks later. Fresh apples will keep a couple of months in the refrigerator. Just be sure to watch for warning signs like off-putting odors, colors or flavors, which can indicate spoiling [source: Eat By Date].

You also may consider using the freezer to extend your consumption range. Raw chicken breasts, for example, could be stored in your refrigerator for a couple of days, while a cut of beef could keep for up to five days. Transfer either of these — or other perishable items — to the freezer and it will be safe indefinitely. It may not taste great after existing in subzero temperatures for two years, but it will still be safe to eat. You can even freeze milk, although you should plan on using it for cooking rather than drinking because of the change in taste [sources: USDA, Dairy Council of California].

Canned goods and shelf-stable foods like boxed macaroni-and-cheese have greater latitude than their perishable cousins. Unopened, they can be eaten a year or two past their expiration dates, although there have been more extreme examples. In 1974, scientists at the National Food Processors Association in Washington, D.C., opened and studied a 40-year-old can of corn, along with 100-year-old canned oysters, tomatoes and red peppers. The food looked and smelled edible and even retained most of its nutrients, save lower levels of vitamin C. Although the scientists didn't stage any tastes, they believed the food would have been safe to eat. That's good news for all the preppers out there stockpiling canned goods in their bunkers [source: Charles].