Top tips for shelf life dates. When should food be thrown away?

Posted: 22nd January 2018

Top tips for shelf life dates. When should food be thrown away?

Ever wondered what is the difference between the dates on food? Best Before (BB) and Use By (UB) dates. Are you confused? Have you thrown away more food than you need to?

Have you thrown food away because the BB date was up, or kept food beyond its UB date, because “the retailer always shortens it, don’t they!”

The difference between the two types of shelf life dates is that Best Before (BB) is all about quality, and Use By or UB is all about safety.

Which date is used for which type of food?

The types of food that have a Use By is those which would support the growth of pathogens (disease causing micro-organisms) if their growth wasn’t controlled by temperature control or another type of food preservation, like drying or adding preservatives.   Examples are meat, ready to eat products like sandwiches, cooked meats, prepared vegetables and dairy products.

Products which carry a BB are being marked as the product “as sold” is unlikely to cause food poisoning if the packaging is undamaged. Often, there is a recommendation for a period to eat the food within on these packs, or a “Once Opened consume within” period of time. For example, canned fish is safe if the can is not opened for months and will carry a BB. Once opened, however, it needs to be treated as fresh fish. It will carry a notice that reads something along the lines of -“If not consumed immediately, keep refrigerated and consume within a period of time”. There may also be advice regarding the type of storage container or conditions.

How do manufacturers check?

For example, for biscuits, the shelf life may include eating quality over a period of months with a microbiological test at the end. For a fresh ready meal, the shelf life test will include regular microbiological testing as well as eating quality or organoleptic testing.

Urban Myths

Manufacturers of food have an obligation to conduct shelf life tests and keep records of these. It is also in the retailer and manufacturers’ interest to keep the food available for sale as long as possible. There is no “couple of extra days” available for the consumer past the Use By date. I think that this is a legacy of the previous system of Sell By or Display Until and Use By dates. In the past, a retailer would remove food from sale at the Display Until or Sell By dates, and the customer then had until the Use By date to eat it.

So, in essence the Use By date is a food safety date and food should not be eaten after this date. A Best Before date is for quality and most people don’t mind a slightly dry chocolate biscuit.

Don’t throw food away, just because the BB date is passed.


The Food Standards Agency (FSA) has a page of legislation about this

For more information about food safety, look at the Alimenti blog