April 20th, 2009
01:51 PM ET

What’s the truth behind all those food expiration labels?

By Karen Denice
CNN Medical Senior Producer

What does the “Sell-by” date really mean?

Is the sell by date really a “consume-by” date? Everyone seems to have an opinion, but what are the facts? I was raised to never waste food. My grandfather used to cut the mold off my bread and hand it back to me. So, I have a rather liberal view of food safety – more of a sniffer than a by-the-book, go-by-the-date kind of gal.

But recently I was having friends over for dinner and wondered if I could be putting them at risk. The meat I was using had only a sell-by date and had been frozen every minute since then. Granted that sell-by date was in September and I was cooking for them in March. Don’t flinch!

For the dinner I used my personal sniff, color and texture test and decided it looked good, but that just made me wonder what do those dates on packages really mean? So I did some research.

Surprisingly food dating is not generally required by the federal government although 20 states do require it. There are multiple “dates” that may end up on your food; the one in question for me was the purchase or sell-by date. These dates are not an expiration date, but they do reflect when the food is at its highest quality. Depending on the food, it will stay good anywhere from one to two days [poultry] to five weeks [eggs] after the sell-by date if handled properly. (Check out this chart)  

There are also “Best if used by” or “Use-by” date stamps. These sound like your food might go bad, but again the U.S. Department of Agriculture says this refers only to the quality of the food – not safety.

If you freeze food the dates and advice gets murkier. Experts say freezing prevents the germs that cause food to spoil, but that doesn’t mean you’ll like the taste when it’s defrosted. Anything from freezer burn to how long it was frozen and the quality of the food will impact how good, or not good, it will taste.

Lucky for me, my friends enjoyed the meal and as it turns out it was unlikely they would have gotten sick anyway.

So are you a sniffer or a by-the-date person? Have you ever gotten sick taking a risk?

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soundoff (15 Responses)
  1. Larry

    I once got sick after eating frozen turkey that had been frozen for quite some time. I was under the impression that frozen food did not go bad, however I have to wonder if it didn't get accidentally defrosted at some point. Otherwise I've never gotten sick from food unless you count lactose intolerance, but thats a whole different issue.

    April 22, 2009 at 11:37 | Report abuse | Reply
  2. Wren

    I'm a combination sniffer and by-the-date person. I find lately none of my milk ever makes it to the date on the bottle. It always goes bad at least 2 days early. After a couple disgusting cereal incidents, I always smell my milk even if I just bought it yesterday. I also tend to go for "if it's slimey and it shouldn't be", throw it away. I'm also pretty good at smelling mold, since I'm allergic. Food will usually smell moldy before you can see it. If something like salad dressing is months past the date but it still looks/smells good, I will throw it away anyway.

    April 22, 2009 at 14:04 | Report abuse | Reply
  3. Alex

    This was good timing for this article.

    Last week while making some pasta I realized that I did not have an unopened container of pasta sauce. (somehow it missed the list) I did however have a partially used container in the refrigerator. I checked the date and it was in the future so that was a good sign. I took the lid off and bravely stuck my nose to the edge of the jar and sniffed. Smelled like Pasta sauce! I also didn't see anything out of the ordinary in the jar. I was home free!
    After dumping in the sauce, mushrooms, and everything else that makes a good pot of pasta, I happened to look over and see the lid from the pasta jar. In the middle of the lid was a large, fuzzy clump of greenish-blue mold! NOW was a real dilemma. Since I was the only one who would be eating it and I had an appointment the following day I would have rather missed, I ate it anyway. I did make sure to cook it a little hotter and a little longer than usual.
    Much to my surprise I didn't get sick at all!

    April 22, 2009 at 15:00 | Report abuse | Reply
  4. Dr.P.S.REDDY

    Foods like Meat, Fish,Chicken etc., when once frozen for a period,later on kept at frig temperatures(8 degrees centigrade),loose their quality.They should not be refrozen.It is better to use the foods from deep freezer immediately after their removal from the deep frig.

    April 22, 2009 at 17:06 | Report abuse | Reply
  5. DrD11

    Since Medication are also "Food",this forum should cover this subject involving expiration date of ingridients.
    Not as with food,there is no issue with spoiled taste,just issue with safety.

    April 22, 2009 at 23:19 | Report abuse | Reply
  6. Leah

    I got sick after eating raspberrys. I had taken them on a camping trip & noticed that some of them had mold growing on them, so I picked those ones out & just ate a couple, then decided to throw them away, but then I started puking my brains out for 2 days. Raspberries were from Vons (Safeway), they were old when I purchased them on sale.

    April 25, 2009 at 12:36 | Report abuse | Reply
  7. sunshine09

    The adage, "When in doubt, throw it out" and faithfully checking the sell by and use by dates works for me.

    April 26, 2009 at 11:44 | Report abuse | Reply
  8. RC

    I don't use foods past their expiration date and I do "sniff test" questionable foods prior to it. If it's slimy, smells funny, or looks funny, I don't care how far off the expiration date is in the future, I'm not eating it. And I also take care to try and remember that often expiration dates are for *unopened* foods, meaning once they're opened you go by a new set of rules.

    Food poisoning isn't anything to sneeze at or just mild discomfort, so I don't take risks.

    April 27, 2009 at 19:20 | Report abuse | Reply
  9. Yellow

    I found out from personal experience that it is always best to use before the date and not a month after. After eating chicken with an expired date i became very ill. Before i ate the meat i really didn't think it would be much of a problem because i remember my mother telling me that frozen meat was fine as long as you did not freeze it after it's been in the fridge and frozen again. Well i didn't think a month could make that much of a difference, and about a few hours after eating i became very ill. I've been know to get food poisoning often and i don't take well to many foods, so i knew that it had to be the last thing i ate. After going to see my doctor i informed him of everything i had eaten that day and also informed him that the meat was expired. He went on to tell me that if it wasn't properly closed right that something could had possible contaminated that the date wasn't really that far off and that the date is for the stores to sell the product by. I've now taken more precaution when it comes to what i eat and their packaging

    April 28, 2009 at 01:54 | Report abuse | Reply
  10. Dave

    There are two significant factors that people should take the time to understand about food degradation.
    First, the date is a very crude approximation. An accurate indicator would be a time-temperature meter since temperature is much more significant than time alone is.
    Second, there can be a big difference in remaining shelf like whether the food has been opened or not. For example, ultra-pasteurized dairy products may last a long time unopened, but lose the ultra when opened.
    Both of these issues are why we own refrigerators. On occasion you might see on a milk container with a graph showing how a few degree decrease in storage temperature can double the shelf life.
    Also, freezing generally dosen't do anything to the germs except keep them from growing for a long time.

    April 28, 2009 at 10:55 | Report abuse | Reply
  11. Sharleen Biever

    Recently mt adult children became upset with me because of all the outdated medicine, both OTC and Prescription, that I had in the medicine cabinet. I have never had a reaction from outdated medicine and after this article on food dating I would like your answer on medicine dating.
    Thanks for all the tips and info you provide for everyone's education.

    April 28, 2009 at 12:30 | Report abuse | Reply
  12. Mary

    Sharleen: My neighbor (a pharmacist) has told me that in general meds do not go bad, they lose effectiveness with age. I'm sure there are exceptions.

    April 28, 2009 at 12:37 | Report abuse | Reply
  13. jamie

    My mom always said..when it doupt throw it out, so i live by those rules, if you have to question the food you are about to eat, then i just toss it.

    April 28, 2009 at 12:54 | Report abuse | Reply
  14. Allison

    I don't even let my food get *near* the date!

    Just buy little and shop often and your food will always be not only safe, but more tasty and nutritious!

    April 28, 2009 at 18:40 | Report abuse | Reply
  15. Lee

    Over 20 yrs ago, as written up then in the "New England Journal of Medicine" AND the British "Lancet", research was conducted to check out various "old wive's tales" re: folk remedies. As I recall, they scientifically tested (I am a scientist and understand the nature of testing methods and results) and found only one that worked: by putting a clothespin on the nose of someone with early flu or cold symptoms, the heat in the sinus and nasal passages (which would otherwise normally contain colder outside air) seemed to kill the virii. One company, maybe Swiss, came out with a heated anti-viral aerosol dispenser called the Viralizer, I believe, but other than that, the Pharma industry seems happy to ignore this simple and cheap cure (in addition to vitamin C, chicken soup w/ anti-viral agent, zinc, coffee, etc.). It is well known that virii do not like heat, and in fact are most successful when they induce us to turn our metabolic "dampers" down (the most birds getting Avian flu, for ex., are relatively inactive and cool, vs heated inefficient short flights). Over the years at the FIRST subtle sign, I have simply used my fingers to hold the nose tightly closed for 20 – 40 min. I think the pressure adds bloodflow as well as whatever electrical fields are associated with our living system (incl. brain/ nerves). Normally I am NOT getting whatever flu is going around, and every time I wake feeling funny in the middle of the night and do NOT do this, I do get sick. However, later application (hours, not days) significantly reduces sick-time! Everyone I have told of this has reported similar results. So this is slightly beyond "anecdotal".

    April 29, 2009 at 09:50 | Report abuse | Reply

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