Shoppers usually take food home from the supermarket but in Brighton they will be asked to leave some behind this weekend.
At Sainsbury’s in Lewes Road, Brighton, customers will be asked to buy an extra item to give to charity.
The donations will be collected by the national food charity FareShare at the store in Brighton and in 18 other branches of Sainsbury’s as part of a three-day trial.
FareShare tackles hunger in Britain by redistributing quality surplus food from the food industry to people who need it around the country.
The supermarket chain has worked with FareShare since 1994 although this is the first time that customers have been asked to take part directly.
Lindsay Boswell, FareShare chief executive, said: “Sainsbury’s has been involved with FareShare since the beginning, working with us to ensure that good food isn’t wasted.
“If food cannot be sold, but can be eaten, it should always go to people first.
“With this food trial we have a fantastic opportunity to engage with individuals.
“Sainsbury’s customers will be able to support hungry people in their local area in a very tangible way and generally support a charity who offers a very practical solution to the issues of food waste and food poverty.
“We would like to encourage anyone who has an interest in food and supporting vulnerable people to support FareShare.
“With their help, we can feed even more good food to some of the poorest people in our society.”
Hundreds of hostels, shelters and schools benefit from the work that FareShare carries out across the country, including the Fresh Start Community Association.
The Fresh Start Community Association runs several community initiatives working with marginalised groups, including a day centre, drop-in service and out-of-school club.
They provide a cooked meal on site at every group gathering and encourage healthy eating with food support bags for families struggling because of the economic climate.