In North America, several convention centres, including those in San Francisco and Denver, donate leftover food to a program called Network for the Needy.

BBC: Business travel gives back

This has resulted in restaurants offering half portions and free take home bags for leftover food.

BBC: Play your part in the global food crisis

Many food banks now collect leftover foods from hotels and restaurants and redistribute them to those in need.

CNN: Food waste a new opportunity for entrepreneurs