A campaign to cut down the amount of wasted food in New Zealand says the waste is "morally, economically and environmentally outrageous", but small changes can have big impacts.
The Love Food, Hate Waste campaign - which was launched in New Zealand last year - estimates that the average household ditches $563 worth of food annually, which equates to 79kg of edible food going to landfills, or enough food to feed twice the population of Dunedin for a year.
Dr Miranda Mirosa, who has helped to establish the University of Otago Food Waste Innovation Research Group, told Nine to Noon today that food waste looked set to become one of the major environmental and social justice issues of our time.
"One in nine people globally are suffering from hunger, and of course it's not just an issue for developing countries - food insecurity is a real issue here in Aotearoa. We're looking at approximately 17 percent of the population who are food insecure here at home. And people aren't hungry because there is global shortage of food, the food and agriculture organisation of the United Nations is estimating that recovering just half of this amount of food that is lost or wasted could feed the world alone.
She said it was more than just a matter of the wasted product, it was the resources that went into creating it in the first place.
"When we throw away food, we're not just throwing away the food, we're squandering all the resources that have been used in its production, the energy and the water and so forth. Rotting food produces methane which is a greenhouse gas."
She said on a global level, about 30-50 percent of all food that was grown in the world never reached a human stomach, and in affluent countries such as New Zealand, most of the waste came from consumers at the end of the chain.
Bread, fruit, vegetables and meal leftovers were the most commonly discarded items, said Doctor Mirosa.
"We talking the equivalent of 20 million loaves of bread which is thrown into the rubbish bin uneaten every year, just by consumers at home."
Research carried out in New Zealand revealed that consumers were aware of the issue, and were feeling guilty about it.
"About 89 percent of the people surveyed agreed that wasting food felt wrong, so rather than feeling guilty, it's about making small actions and knowing that people can play a part - everyone can play a part in addressing this issue and making a real change."
She said the goal of the campaign was to raise awareness and give tips and strategies to reduce waste.
"It's basic planning, making a shopping list and planning your weekly meals, and the small behaviours that need to be changed that have really big consequences."
Similar campaigns overseas have had some success, said Dr Mirosa. These included a 'clean your plate' social media initiative in china which aimed to shame diners who leave food on the table at the end of the meal, and a European campaign to sell "ugly" vegetables at cheaper prices. Such moves had already seen food wastage drop by 20 percent in the UK.
Being creative with leftovers and making more soups and sandwiches was a step in the right direction, but Dr Mirosa said the key was to get in early.
"While these types of things are obviously better alternatives than disposing of food that is wasted in landfills, but the best possible thing is not create that waste in the first place.
"When we are talking about food waste or food recovery, the best thing we can do is eliminate the waste in the first place. The second best thing we can do is give it to people, and the next thing after that is give to animals or compost."
Overcoming the lack of understanding over the difference between a 'use by' and a 'best before' date was another goal of the initiative, said Dr Mirosa.
"So a 'best before' date is just an indicator of the quality of the food and it doesn't mean the food is unsafe to eat after that date, although a lot of consumers interpret it to mean just that. So getting these sort of messages through is very important as well. Food is perfectly safe and edible after the 'best before' date."
Listen to the full Nine to Noon interview here: