Sidney Baldwin
For the first time in New South Wales, maggots will be eating Sydneysiders' leftovers, leaving local governments looking for solutions to eliminate food waste.
The trial, with circular economy solutions company Gotera, will run over a 12-month period later this year and is expected to transform 600 tonnes of food waste into sustainable feed and fertiliser.
Food waste makes up about a third of the waste in a typical trash bin and releases potent greenhouse gases as it decomposes. In experiments, the larvae of the black soldier fly, which unlike other insects does not carry disease, break down the bacteria in the organic matter it ingests.
“This is the next step in the fight against waste – using maggots is an innovative and sustainable solution to this growing problem,” said Sydney Mayor Clover Moore.
“This is an exciting circular economy achievement, recycling what was once considered waste into a sustainable commodity – both essential for food production: insect protein for animal feed and a natural fertiliser with low environmental impact.”
Gotera founder, 2023 ACTA Australian of the Year winner Olympia Yarger, who is also a farmer by trade, was determined to grow her own feed in her shed and garage.
Justin Frank, Gotera's head of strategy and communications, spoke to City Hub about the process.
“She started with mealworms but soon realised that black soldier fly larvae were her best weapon for eating food waste,” he explained.
“And they have voracious appetites. In our unit they can eat between 1.2 and 1.7 tonnes of food waste a day.”
Holding maggots and compost. Photo: Nick Langley / City of Sydney
The trial process involves collecting food waste from Sydneysiders and feeding it to larvae housed in shipping container-sized units, where they feed and rummage through the food waste.
“And within that unit there's high-density racking, there's robotics and hydraulics that hold hundreds of trays, like plastic tote bags that newborns are housed in,” Frank said.
“The robot moves the trays in sequence to the feeding station, where the maggots busily eat the food remains and then excrete them.
“And at the end of the cycle, you have fat maggots that double their weight every day, so they grow very quickly and produce a very sustainable insect protein.”
“We also have a bio-protocol for us called maggot manure, which is a very sustainable and nutrient-rich fertiliser, but it has no chemicals in it and is a natural pesticide, so it’s really a circular economy.”
The City of Sydney launched a food waste recycling trial in July 2019, with more than 21,000 households taking part, and aims to expand it to the entire population.
Now, they have partnered with Goterra for this new endeavor, and further expansion into food waste management and transformation is on the horizon.
“We'll see how the trials turn out. It should work because maggots love to eat food waste. After that it's just a matter of coming to an agreement to expand,” Frank said.
