The issue is in the spotlight because France has a new law stopping supermarkets destroying unsold food. Instead, chains have to donate old food to charities or find a use for it somewhere else.
WasteMINZ chief executive Paul Evans said although he could see merit in what the French were doing, the key offenders were citizens who needed to take more responsibility for their waste.
McDonald's NZ spokeswoman Kim Bartlett said the company realised it could be doing more and in December carried out a "waste audit" to try to work out among its 164 stores how much food was being thrown away.
Ms Bartlett, who kickstarted the project, said sustainability was a focus McDonald's business.
The company recycled all of its cooking oil, she said.
A spokesman for Restaurant Brands, which owns Pizza Hut, KFC and Carl's Jnr, said operations were "very tightly controlled" to ensure food waste was kept to a minimum. Its biggest waste product - cooking oil - was also recycled.
Michal Haines, general manager of Farro Fresh, said leftovers were donated to Fair Foods which then redistributed them to needy families.
Garry Croft, general manager of Muffin Break parent Foodco, said the 39 franchises didn't have a specific policy but hoped owners would use a common sense approach to tackle any leftovers.
Richard Manaton, Countdown's general manager for strategy and corporate affairs, said its leftovers were donated to its charity partners.
A Foodstuffs spokesman said the majority of its stores already donated to local charities. The company worked with waste provider Envirowaste to divert products to animal stock feed, rendering plants or composting sites.
Food and Grocery Council chief executive Katherine Rich said she didn't believe a law mirroring the French was needed.
" ... regulation brings cost and additional bureaucracy because they're going to have to have people who go around and check that people are complying."
The Salvation Army's Major Pam Waugh said while impressed by what the French had done, she would have concerns if something similar was implemented here as not all charities had the infrastructure to manage the large amount of product involved.
Who does what?
McDonald's NZ carried out waste audit.
Restaurant Brands wouldn't reveal stance, but operations "tightly controlled".
Farro Fresh donates to Fair Foods.
Muffin Break no policy, up to individual owner.
Brumby's bakeries charities.
Baker's Delight must be given away.
Countdown variety of charity partners.
Foodstuffs charities, including Food Harvest.
Fruit World no policy, stock sold off cheap or given to pig farmers.
Nosh no comment.
