The Oxfordshire sustainability body thinks they should also be sold loose.
Around a fifth of food brought into UK homes ends up as waste - including £4 billion worth of binned fruit and vegetables.
Experts at WRAP in Banbury have come up with new guidelines, after examining 2,000 food products in 60 supermarkets for a new report.
It looks at progress by individual retailers and says more needs to be done in implementing best practice for packs and labelling to help cut household food waste.
The research found that a quarter of all pre-packed unprepared fresh produce now carries no date label, while the available shelf life of other products, such as milk, has increased.
Peter Maddox, Director at WRAP, explains “The way food and drink is packaged, labelled and priced can influence household food waste, and retailers and brands are uniquely placed to help minimise food waste in the home.
"Our research shows that people want clear, consistent information on pack to help them keep food fresher for longer. Overall, we’ve seen good progress from all, but we have also been very clear with each company where more work is required, and where they are falling short."
The Food Standards Agency and Defra also helped to produce the new guidance, which will help retailers identify where more fresh produce can be sold loose*, and reduce the application of Best Before dates on some pre-packed fresh produce – where it can help reduce food waste at home.
- More than one-fifth of items found on shelf had just two days or fewer remaining life; including bread, minced beef and berries. For milk, an increase in 1.5 days of available shelf life was noted, which WRAP says 'is excellent as an extra day alone could help reduce household milk waste by more than 20,000 tonnes per year.'
- A quarter of all pre-packed unprepared fresh produce now carry no date label, which aligns to the updated guidance. Three retailers have removed Best Before on some fresh produce, with another committing to remove them from selected produce.
- There has been a significant increase in the use of the snowflake logo, rising from 15% to nearly 50%. The number of bread items now carrying the snowflake has doubled to 79%. WRAP says freezing 'is a key way to extend life of bread items and reduce the likelihood of it being wasted.'
- Little evidence was found of retailers having implemented guidance to remove open life statements except where food safety is an issue. For example, for hard cheese the average available life for block cheddar was 64 days, but 90% of packs carried advice to use within 5 or 7 days of opening. Nine retailers are now reviewing or amending open life on yogurts and cheese.
- Bagged salads typically have very conservative Open Life of just one day and more could potentially extend this.
- More than 70% of fresh potatoes carry a Best Before label and the average available product life has decreased by around one day (to four days). More than 10 percent of 2.5kg bagged white potato, when surveyed, had less than two days available product life.
WRAP wants the phrase “Freeze on Day of Purchase” stopped, saying it can lead people to throw away good food, instead of freezing it up until the date mark. Three retailers have completely removed this and eight more are removing the remaining few products with this statement.
Peter Maddox continues, “Public concern has grown over plastic packaging since our last survey, particularly around fresh produce, and we have updated our guide to address single use, problematic plastics in this category.
"Removal of packaging must be done carefully to avoid food waste, and we now we have a clear set of principles that will help limit plastic use, and ensure removal is done in a safe and sustainable way."