About 40 percent of food is wasted globally, and New Zealand is not doing much better. File photo. Photo: 123RF
A lot of food waste happens before it gets to consumers, a new report on the problem has found.
About 40 percent of food is wasted globally, and the prime minister's chief science adviser Dame Juliet Gerrard - whose office wrote the report - says there is no evidence Aotearoa is doing any better.
She says while there is a lot individual shoppers can do to help, a lot of waste is beyond their control.
The report said preventing food loss and waste at source had the greatest potential benefits, while narrowly focussing on household decisions could only solve part of the problem. About a third of food loss happens in homes, according to Australian estimates.
The report recommended setting a target of halving food loss and waste by 2030.
Gerrard said there were changes available at every step of the process.
"If you are [a farmer] supplying a major retailer, you sign up to a particular agreement to say you'll supply a certain amount of produce to particular specification. You don't want to be in breach [so] to meet those terms, there's a huge incentive to overproduce," Gerrard said.
"If you're [a shopper] going to the supermarket and there's a three-for-the-price-of-one special you might buy it. That takes the food waste off the books for the supermarket, but doesn't stop the food being wasted if it just sits at the back of your fridge."
"So much of it is out of the consumer or eater's control and this report lays that out," said Kaitlin Dawson, executive director of NZ Food Waste Champions, who helped launch the report.
But Dawson said customers had a part to play, too - for example, rejecting slightly damaged produce or only taking the newest items.
"The most wasted item in New Zealand is bread, but not just at the household level. How full are the bread shelves at your local supermarket? They keep them pretty stocked because that's what we expect and... there's often a lot of wastage at the end of the day."
Packaging large quantities of food together could encourage waste, she said, as could 'best before' dates, which put people off selecting items that were still perfectly edible.
Another of the report's recommendations was food sectors - such as bread or tomatoes - getting together to tackle waste all along the chain, which Dawson said had worked effectively overseas.
She said overseas experience had shown voluntary business groups could lead the way, but at some point that reached a limit and government regulation was needed.
'So much more we could do'
At Fair Food's warehouse in the Auckland suburb of Avondale, trucks arrive carrying bread, eggs, milk and produce from supermarkets, all of it edible but unsellable because it is damaged, surplus or nearing its 'best before' date.
A lot of it is bread or bananas.
When RNZ visited, senior driver Vasene Pua was unloading box after box of bananas, which he said were perfectly fine but had been sent by a local Countdown because they were unlikely to sell.
Manager Michelle Blau was overseeing rows of volunteers, who were hand-sorting items from the trucks into food fit for fresh food parcels, which would go to hungry people; lightly damaged items like soft carrots or bruised tomatoes, which would be cooked by chefs into a curry; and food unfit for humans, which would go to piggeries.
She said more bananas arrive each day than they can give away - bananas are "highly cosmetic" and susceptible to being rejected by shoppers for minor blemishes, she said, plus they are imported to New Zealand in bulk.
Fair Food has struck a partnership with an ice-cream company to make banoffee-flavoured ice-cream and sell it to fundraise for the organisation, she said.
Bread was sorted at the supermarket pick-up point before the drivers pick it up, then its put into one of three bread bins at the Fair Food depot: called Fat Breadies Drop, Breadie Mercury and Ziggy Starcrust. All the working parts of the warehouse have names, Blau said.
"Last week we shared 13,973 kilos of food with people and 1165 kilos went to our local pig farmers, and when you add that up it's 37 tonnes of emissions saved," she said.
"I actually give a lot of credit to the supermarkets because they have a choice about partnering with us. They really do the right thing and think ahead and think, if no one's going to buy that let's pull it off the shelf now while it's still good."
Blau said food rescue centres could do "so much more" if they had better resourcing, for example reducing waste from the 90 percent of New Zealand's food production made for export. This food might be rejected if turns out less-than-perfect, but be perfectly edible, she said.
"It's one thing for something to have an export value and be sold around the world, it's another to say, is this good food for people?".
Dawson said current levels of waste are a problem, given 15-20 percent of New Zealanders don't always have enough to eat, despite enough food being grown to feed them.
It was also a problem for curbing climate change.
About four percent of New Zealand's planet heating emissions are from food breaking down in landfill, creating methane, a potent warmer. That does not count the wasted emissions from producing uneaten food in the first place.
"Every single stage of that item of food being grown, packed, picked, manufactured, transported, put on our shelves.. .if we then waste that food, all of those emissions are wasted," Dawson said.
She said some waste happens at farm level - such as if a glut meant broccoli prices dropped so much that it was cheaper to let the vegetables rot, than to harvest and sell them.
But growers are too busy to find ways to use the surplus, so they need help identifying options such as food charities, juicing, powders or other avenues, Blau said.
Gerrard added that not only does growing and wasting food create planet-heating emissions, climate change itself is contributing to food waste.
For example, climate change-fuelled cyclones have devastated food growing regions, or broken supply chains leading to gluts of food like kiwifruit.
The report concluded solving the problem would require a co-ordinated approach.
But Dawson had one small tip anyone try do in the meantime - she puts half of every loaf of bread in the freezer as soon as she buys it.