Food Expiration Dates: What Do They Really Mean?

Some of us adhere to them with religious severity and others use them as an insignificant suggestion, but either way, expiration dates are mysterious. They seem to suggest that we should stay far away from foods marked with a calendar date that's passed, but is that what they really mean?

According to the USDA, expiration dates are not a safety date. However, the USDA does recommend that if a product has a "use-by" date, you should follow that date. They also define the different expiration terminology. The "Sell-By" date suggests you buy the product before the printed date, but it doesn't indicate that the product has spoiled. And the "Best if Used By" date suggests consuming that product before the date for optimal quality.

But the amount of time an item stays safe to eat largely depends on how it is stored, not how long it's been produced for. Milk kept in the fridge will unquestionably last significantly longer than milk left out on the kitchen counter.

And since "more than three-quarters of U.S. consumers mistakenly believe certain foods are unsafe to eat after the expiration date has passed," reports The Boston Globe, we feel that it's time to get the facts straight. Don't waste your money by throwing out foods with expired dates. Click through the slideshow below to see how long common grocery store items remain safe to eat.

The information for the life span of food items was found on StillTasty.com. If curious about the expiration dates on other products, visit their site for more information.

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• Ketchup

  Ketchup will maintain its quality for six months in the fridge. It's still safe to eat after this date (unless it has developed an off odor or mold appears). Photo by <a href="http://www.flickr.com/photos/doobybrain/213828192/sizes/l/in/photostream/" target="_hplink">Flickr: doobybrain</a>.

• Olive OIl

  Olive oil can stay fresh for 18-24 months either in or out of the fridge. It is recommended that you keep it in a cool dark place -- and refrigeration is suggested if you live in warm climates. Most times, you will have long finished the oil before it comes even close to perishing. Photo from <a href="http://www.flickr.com/photos/bhamsandwich/4665992253/sizes/l/in/photostream/" target="_hplink">Flickr: bhamsandwich</a>.

• Eggs, Raw In The Shell

  Eggs stay good for 3-5 weeks in the refrigerator and up to one year in the freezer (note: it's not recommended to freeze them in their shell). Eggs will normally keep long past the sell-by date; but to ensure that they last as long as possible avoid storing them in the refrigerator door -- the coolest part of the fridge is best. Photo from <a href="http://www.flickr.com/photos/ambernectar/3803765911/sizes/l/in/photostream/" target="_hplink">Flickr: Ambernectar 13</a>.

• Milk, Pasteurized

  Milk will stay good one week past the sell by date, and three months in the freezer. But of course, if milk has developed on off odor or flavor, it's best to discard it. Photo from <a href="http://www.flickr.com/photos/loop_oh/3030317020/sizes/o/in/photostream/" target="_hplink">Flickr: loop_oh</a>.

• Yogurt

  You have a 7-10 day window after the sell by date to enjoy your yogurt, (and one to two months if stored in the freezer.) But if mold appears, discard the yogurt. And if it was frozen, it's best to thaw it in the fridge. Photo from <a href="http://www.flickr.com/photos/lovemaegan/4483171610/sizes/o/in/photostream/" target="_hplink">Flickr: ...love Maegan</a>.

• Mayonnaise

  Don't throw it out just yet! An open jar of refrigerated mayonnaise is safe and good for consumption up to 2-3 months after the marked expiration date. And even then, the product may still be safe to eat, it just might begin to change in terms of texture and color. Photo from <a href="http://www.flickr.com/photos/clango/487259906/sizes/l/in/photostream/" target="_hplink">Flickr: clango</a>.

• Peanut Butter

  An open jar of peanut butter will remain fresh up to three months in the pantry. After that point, it's recommended to store the peanut butter in the fridge (where it can maintain its quality for another 3-4 months). If you don't refrigerate, oil separation may occur. Photo from <a href="http://www.flickr.com/photos/cantoni/6398248857/sizes/l/in/photostream/" target="_hplink">Flickr: brianc</a>.

• Pickles

  Pickles, once opened, stay good for a whole year in the refrigerator. So if you've just come across a jar in your fridge, chances are, they're still delicious. Same goes for brine-packed jars of olives and capers. Photo from <a href="http://www.flickr.com/photos/ejchang/4823204395/sizes/l/in/photostream/" target="_hplink">Flickr: sleepyneko</a>.

• Soy Milk

  Despite what you might think, soy milk has a similar self life to regular milk. It lasts about 7-10 days after the date indicated on the carton. Photo from <a href="http://www.flickr.com/photos/theimpulsivebuy/5180297645/sizes/l/in/photostream/" target="_hplink">Flickr: theimpulsivebuy</a>.

• Sour Cream

  Sour cream is a tough food item to judge, since it's supposed to have a slightly soured taste. It can keep two weeks, tightly covered, in the fridge. And unlike most other dairy products, it doesn't freeze well. Photo from <a href="http://www.flickr.com/photos/mogula/6987170303/sizes/l/in/photostream/" target="_hplink">Flickr: limin_chiu</a>.

• Vinegar

  The shelf-life of vinegar is almost indefinite <a href="http://www.versatilevinegar.org/faqs.html">according to versatilevinegar.com</a>. Aesthetic changes such as color or the development of sediment may occur in non-white vinegars over time, but the product is still safe to use. Photo from <a href="http://www.flickr.com/photos/felishumanus/484150776/sizes/o/in/photostream">Flickr: felishmanus</a>

• Honey

  Even more so than vinegar, honey's quality remains unchanged over time. The low water content and high acidic level makes the food an unfavorable breeding ground for bacteria, in spite of its sugary nature. Photo from <a href="http://www.flickr.com/photos/cygnus921/3712930982/sizes/l/in/photostream/">Flickr: cygnus921</a>

• Mustard

  When purchased at a store, mustard lasts anywhere from one to two years past its expiration date. This variation is due to differing storage methods -- when left unopened in the pantry, mustard lasts an extra year. Homemade mustard doesn't have the same shelf life, and expires much more quickly. Photo from <a href="http://www.flickr.com/photos/lifeontheedge/2316757256/sizes/l/in/photostream/">Flickr: Marshall Astor - Food Fetishist</a>

• Almond Milk

  Just like milk and soy milk, almost milk lasts 7-10 days past its printed date, unless it's stored unopened in the pantry, in which case this beverage can stay good up to a month after. <strong>Photo from <a href="http://www.flickr.com/photos/aarongustafson/123422518/sizes/m/in/photostream/">Flickr: Aaron Gustafson</a></strong>

• Whipped Cream

  Canned whipped cream can last up to three months past its printed date, whereas Cool Whip only lasts about 7-10 days. Photo from <a href="http://www.flickr.com/photos/stevendepolo/5159788513/sizes/l/in/photostream/">Flickr: stevedepolo</a>

• Butter

  Plain ol' butter lasts about 2 weeks after its expiration date; Butter with olive oil lasts about a week more than that. Stick butter in the freezer and it can last up to 9 months longer. Photo from <a href="http://www.flickr.com/photos/sionakaren/3871517484/sizes/l/in/photostream/">Flickr: Siona Karen</a>

• Half and Half

  Once opened, half and half, and all other liquid creams, last about 5-7 days after their expiration date. Photo by <a href="http://www.flickr.com/photos/greencolander/1463911167/sizes/l/in/photostream/">Flickr: Greencolander</a>

• Coffee

  An open container of ground coffee will last 3 to 5 months past the best before date, whereas coffee beans will last up to 6 months. Photo from <a href="http://www.flickr.com/photos/epsos/8097327748/sizes/l/in/photostream/">Flickr: EpSos.de</a>

• Pasta

  Dry pasta may seem to have an infinite shelf life. It doesn't, but it has quite a long one -- It'll last 1-2 years past the best before date. Photo from <a href="http://www.flickr.com/photos/duncan_h/4201489578/sizes/l/in/photostream/">Flickr: Duncan H</a>

• Deli meat

  Packaged lunch meats last about 7-10 days longer than the best by date, whereas fresh meats will last around 5-6 days. Salami and pepperoni last much longer -- around 2-3 weeks. Photo from <a href="http://www.flickr.com/photos/stuart_spivack/67351962/sizes/l/in/photostream/">Flickr: stu_spivack</a>

• Syrup

  Syrup may get thicker or darker when it gets older -- it may even crystalize. But it is never technically "spoiled." Photo from <a href="http://www.flickr.com/photos/26085795@N02/4173693000/sizes/l/in/photostream/">Flickr: jemasmith</a>

• Tea

  Whether your tea leaves are packaged or loose, they'll last anywhere from 6 months to a year past their expiration date. Photo from <a href="http://www.flickr.com/photos/tenderisthebridge/269425312/sizes/l/in/photostream/">Flickr: Scout Seventeen</a>

• Spices

  With the exception of mint, which has a slightly shorter shelf life, most spices from cinnamon to cayenne pepper last 2-3 years past their expiration date. Photo from <a href="http://www.flickr.com/photos/crobj/5519129659/sizes/z/in/photostream/">Flickr: srqpix</a>

Comments

[rucontento2]

12:01 PM on 05/29/2012

Too many times I buy items and the dates are not readable... They are often too small or printed over the ridges on top of a can. Sometimes they are printed too lightly. Odften the date is printed on a dark color. Other times the date has to be decifered from an entire list of numbers - which one is which??? Clarity and printed on a readable surface should be a requirement... I am tired of the "buyer beware" attitude. MAKE THOSE DATES CLEAR!!!

[Jessica Baumgartner]

03:27 AM on 05/27/2012

real food is not meant to last as long as the USDA has structured our "food" to do so these days. everyone should watch the documentary "food, inc." and rethink their grocery store habits.

[Hannah F]

03:10 AM on 05/27/2012

You misspelled mayonnaise.

[treacle234]

09:11 PM on 05/24/2012

Storing peanut butter in the refrigerator makes no sense. When you are in a hurry and need a quick pick up snack it's frozen. so nooo. Store it on the counter top

[theaverment]

11:33 AM on 05/24/2012

When in doubt throw it out.

[javagirl023]

09:59 AM on 05/24/2012

Oh, and btw, I work in a grocery store, we get meat packed in the foam trays with plastic on top. It is not a sign of spoilage if the top is inflated, they replace air with nitrogen (?) which causes the bulge. Some meat packed this way spoils a day before experation, some I have had has been acceptable days after the date. Color and smell is a better indicator of freshness than date.

[Tony Twohill]

05:12 AM on 05/30/2012

Not necessarily color. Many red meats become brown when they touch each other, and certain kinds of lighting will cause them to lose their redness early.
Most big chain stores have corrected for the lighting issue and changed the types of bulbs they use in their meat cases.

[javagirl023]

08:40 AM on 05/30/2012

And actually I failed to address the issue that very beautifully aged beef is darker--more cranberry in color than is fresher beef anyway, but since that is not available in grocery stores generally, I did not address it. And since you can't smell through the packs, I go by color/proximity to freshness date. Funny enough, same issue with potatoes, the lighting thing, I mean. Potatoes that are green are mildly toxic, but if they turn green in the store from the artificial lighting, the green is safe to eat, though I don't. Loved your comments, I love coming across cool little nuggets of info as with your post. I knew we had special lights in the cooler, I didn't know why.

[javagirl023]

09:56 AM on 05/24/2012

Oops, I meant to say the creamery batches from "fewer" farms.

[javagirl023]

09:55 AM on 05/24/2012

Actually, if many cultured dairy products are unopened, they can be still fresh for as long as a month after the experation date. Also, I use real cream for my coffee, conventional cream often expires three or four days after the date--within the safe limit in this article, but the really good organic stuff I buy can last several weeks after the date, plus it tastes better. (I suspect that the small cooperative batches product from different farms, faster than the big guys.) Either way, use common sense, smell, look at, inspect, and don't use anything suspicious, but don't throw out just because it expired.