An episode of BBC2's fly-on-the-wall documentary Superstore, filmed at Tesco's Banbury branch, to be screened next month, will reveal for the first time that pounds 3,500 of produce is binned every week at a single store.
Until now the exact levels of edible food being wasted has been difficult to quantify, as the big supermarkets are reluctant to give figures. Despite calls from homeless charities and food organisations, only a tiny amount of waste food is being passed on to charity.
Jacqui Webster of the National Food Alliance, said: "Wastage is a serious problem and it is something that needs to be addressed. The amount that is being thrown away is incredible."
The supermarkets are wary of giving food directly to the homeless, preferring to work with specialist distribution charities who will ensure substandard food is not passed on. But the number of charities capable of doing this is small, and food at the majority of supermarket branches which are not near a distribution centre is being destroyed.
An estimated pounds 6.7m worth of food is being thrown away every week by supermarkets - enough to feed 370,575 homeless people.
Captain Bill Cochrane of the Salvation Army said: "There is enormous scope there for us passing on good quality food. We have a network of more than a thousand Salvation Army centres and all of them will be near a supermarket.
"I can understand their anxiety about making sure the food is safe but those are anxieties we share. The last thing we would do is put anyone at risk."
Marks and Spencer is the only supermarket where all edible waste food is passed on to charity.
Of the other supermarkets, just 100 Tescos out of 588 branches participate in Provision, a distribution charity set up by the Institute of Grocery Distribution. Tesco staff have orders to throw out all their waste fresh food.
Out of 389 Sainsbury branches, 10 supply the FairShare scheme run by the homeless charity Crisis, which specialises in fresh food. Other food is donated to Provision through the supermarket's head office.
Of Waitrose's 117 branches, 20 stores supply goods to Provision. This is being increased to 48 branches next month.
Safeway is a member of Provision and also gives some waste food to zoos. A spokeswoman could not say how much food is being binned but said the company was improving waste management.
All the supermarkets said they were committed to expanding their level of involvement in distributing waste food to charity. Until they do, millions of pounds worth of good quality food will continue to end up in land fill sites and incineration centres every week.
As supermarkets are especially wary of giving away fresh produce for fear of food poisoning, almost all is currently being destroyed. Only two charity centres in the whole of the country, one of which is supplied by Sainsbury, cater for the distribution of fresh food.
Stephen Bromberg, spokesperson for Crisis, which runs FairShare, said: "We know that three in five homeless people do not have fresh food in their diet at all so this is the food we really need to give to them.
"And there is no reason why supermarkets shouldn't give fresh food. We can stop safety being a problem. We guarantee we can get food out of the supermarket and to homeless centres by the following lunch time."
Maya Van Eerde, spokesperson for Marks and Spencer, said individual branch managers made arrangements with local charities who signed a contract taking on responsibility for food safety.
She said: "We haven't had any problems and we've been doing this for a long time. The charities are so grateful to receive the food they stick to the contract and as far as we're aware it works very well."
As well as finding ways to dispose of waste food, supermarkets are attempting to cut down on wastage, turning to sophisticated schemes to regulate the supply side.
Other initiatives include reducing food as it approaches its sell by date or putting it in staff canteens.
Martin Bowden, who has been seconded to Crisis by Sainsbury, said the supermarket hoped eventually to pass all its safe waste food, including fresh produce, on to the homeless.Reuse content