Image caption "Best before" is not the same as "use by". But do consumers understand the difference?

"Best-before" dates on food could be reformed, the UK government has indicated. But what purpose do they actually serve?

Ministers say they are in for a shake-up, but "best-before" labels are a familiar sight to every British shopper.

Current guidance from the Food Standards Agency says they are supposed to tell the consumer more about "quality than safety" - indicating when a product may begin to lose its flavour and texture, but not that the product becomes dangerous to eat.

By contrast, "use-by" dates apply to food that goes off quickly, such as meat products, which may put health at risk if eaten after a certain time period.

Anti-waste campaigners argue that "best before" encourages consumers to throw out products that may be perfectly fine - but the retail industry says they are a reliable guide which help consumers plan ahead.

By law, pre-packed food must display a "best-before" date.

The answer Best before is about quality not safety. Food should be safe to eat after this date, but it might not be at its best. One exception is eggs

Use by is the key date in terms of safety. Never eat food after this date. Found on cooked meats, soft cheeses and dairy-based desserts

Sell-by and display-until dates are for the retailer, not the customer and are mainly used for stock control purposes

The FSA guidance states that, when this date expires, "it doesn't mean that the food will be harmful, but it might begin to lose its flavour and texture".

One exception is eggs, which the FSA says should not be eaten after their "best-before" date because they can contain salmonella bacteria, which could multiply.

The agency cautions that the date is only reliable if the product is stored according to the instructions on the label, such as "keep refrigerated" or "store in a cool, dry place".

These are distinct from "use-by" dates, which are the most important in terms of safety.

Typically found on meats, soft cheeses and dairy-based items, "use by" refers to a time period after which a product should never be eaten, even if it still appears fresh.

Sell-by and display-until dates are for the benefit of the retailer, rather than the customer, and are mainly used for stock control.

However, the "best-before" label as we know it could be in for major reform as the government has been consulting on ways to simplify food labelling.

According to the advisory body Waste and Resources Action Programme (Wrap), consumers can end up binning up to a quarter of their weekly food and drink purchases - worth £680 to the average British household each year.

Wrap says it has identified confusion over date labelling, with consumers being unclear of the difference between "use-by" and "best-before", as one of the major causes for this.

Environment Secretary Caroline Spelman has said the government is committed to tackling the amount of food thrown away unnecessarily and "if the date labels are part of the problem it's one thing we should be able to improve".

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Caitlin Shepherd of the group This Is Rubbish, which campaigns for a reduction in wasted food, says the primary purpose of "best before" is to protect retail corporations from the threat of litigation.

"It's a symptom of our over-sanitised relationship with food," she says.

"Consumers should be encouraged to related to food in a much more physical way - the best way to tell whether something is still fresh is by having a sniff, having a little taste."

However, Richard Dodd of the British Retail Consortium says it is a "myth" that "best-before" dates are responsible for waste - the best way of tackling this, he says, being improving the way that consumers store and manage their purchases.

"It's about quality and ensuring that the product is of the standard that the customer would expect," he adds.

"It's hard to see how you would get this information across to the customer without dates."