Use by or best before? They are not the same thing

Use by is a safety date

A use by date tells you when food may become unsafe. After that date the food may be unsafe to eat even if it looks and smells perfectly fine, because the concern is microbiological rather than sensory. It is illegal to sell food after its use by date.

You will see use by dates on milk, sliced and shaved meats, yoghurt, cream and dips — products where a pathogen can grow within the shelf life.

Best before is a quality date

A best before date tells you when food may start to lose quality — texture, flavour, colour, nutritional value. Food can legally be sold after a best before date provided it is not damaged, deteriorated or perished.

Canned food, cereals, biscuits, sauces, sugar and flour typically carry best before dates.

What has to be date marked

Any food with a shelf life of less than two years must carry a date mark. Which mark depends on the product, and for anything where a pathogen could grow during storage, use by is generally the correct one.

Why this matters more than it sounds

Two different failures come from the same confusion. Staff who treat a best before as a safety date throw out good stock, which costs money quietly and constantly. Staff who treat a use by as a quality date sell food they are not permitted to sell, which is a far more serious problem.

A third failure is worse again: a business that prints a date without being able to explain where it came from. The date on the pack is a claim, and validation is what supports it. If you cannot show the study or the reasoning behind your shelf life, the date is a guess with legal consequences.

What to do this week

Ask whoever works your coolroom which of your products carry use by dates and which carry best before. If the answer is hesitant, that is the gap. Then check that your own shelf lives have validation behind them — a documented trial, supplier data, or published evidence — rather than being inherited from a previous version of the product.