Australian households throw away a whopping 5.5 million tonnes of left-over food every year – and UniSA PhD candidate Christian Reynolds is on a mission to break the cycle of food waste.
A Fresh Science 2013 finalist, Christian says food waste has reached 'pastry-gate' proportions, with households, industry and governments throwing away enough pies and cakes to fill 24 Sydney Opera Houses in one year.
Christian estimates that over 629,000 tonnes of pies, pastries and cakes were discarded in 2008, with total food wastage across the country sitting at 8.7 million tonnes in that year.
But the humble householder is the biggest offender – with around 9kg of food being dumped from every home, every week.
Christian and his UniSA colleagues have traced the cycle of food waste in a three-year study looking at the economic, environmental and psychological modelling of food waste.
"Households are the worst culprits, accounting for more than half our food waste, with retail, restaurants, wholesalers and the education sector rounding out the top five," he says.
"Now that we have identified the top food wasters, we can tailor programs to reduce food waste in each sector.
"Reducing household food waste has often proven difficult because the reasons for over-purchasing are not rational. To change this behaviour, we need to understand the economic and social factors behind food purchase, preparation, recycling and disposal."
"Not only is food waste taking up valuable landfill space, but it is increasing Australia's carbon footprint through greenhouse gases from decomposition and transport."
But the study was not all bad news. Australian households are engaging in alternative methods of food waste disposal, with an average of 3.2 kilos of food waste per week being diverted to options such as backyard composting or feeding to pet chickens.
"Some local councils now even collect food waste in their green organics bins," Christian says.
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