Food Expiration Dates

Are you like me and you pour milk down the drain on the expiration date?  Expiration dates on food products are really more about quality than safety, and if not properly understood, can encourage consumers to discard food perfectly safe to eat.    

A recent poll of over 2,000 adults showed most of us discard food we believe is unsafe to eat, which is a good thing, of course.  However, it’s important to understand what food expiration dates mean before we throw food and our money down the drain or into the garbage.  On average in the U.S. we waste about 14% of food we buy each year. The average American family of four throws out $600 worth of groceries every year. 

Which five foods are most often feared as being unsafe after the printed date? According to, we are most wary of milk, cottage cheese, mayonnaise, yogurt and eggs, and the site offers these helpful explanations:

  • Milk: If properly refrigerated, milk will remain safe, nutritious, and tasty for about a week after the sell-by date and will probably be safe to drink longer than that, though there’s a decline in nutritional value and taste.
  • Cottage cheese: Pasteurized cottage cheese lasts for 10-14 days after the date on the carton.
  • Mayonnaise: Unopened, refrigerated Kraft mayonnaise can be kept for 30 days after its expiration date or 3-4 months after opening, the company told ShelfLifeAdvice.
  • Yogurt: Yogurt will remain good 7-10 days after its sell-by date.
  • Eggs: Properly refrigerated eggs should last at least 3-5 weeks after the sell-by date, according to Professor Joe Regenstein, a food scientist at Cornell University. Note: Use of either a sell-by or expiration (EXP) date is not federally required, but may be state required, as defined by the egg laws in the state where the eggs are marketed.



Remember the “use by” or “best if used by” date indicates the last day an item is at its best quality for taste, texture, appearance, odor and nutritional value. The decline after that is gradual. The use by date refers to product that has not yet been opened.  And the “sell by” date is not really a matter of food safety, but a notice to stores the product should be taken off the shelf because it will begin to decline in quality after that date.

Cross-contamination and unsanitary conditions are primary causes of food-related illnesses, whether it occurs in the home or in a restaurant, and this is independent of any expiration date. The leading culprits are:

  • Improper hand-washing prior to food preparation.
  • Storing food at the wrong temperature.
  • Cooking food to an inadequate temperature.
  • Cross-contamination (raw meats that come into contact with salads, for instance).
  • Improper washing of fresh produce.


Bear in mind apart from any expiration date, if food is moldy or smells and looks spoiled, err on the side of caution.  If it makes you say, “yuck,” then please throw it away.