Black soldier fly larvae ‘could help solve the world’s food waste problem’

A picture taken on July 17, 2019 shows a dish of Black Soldier Fly larvae which is an ingredient at Gourmet Grubb, a food stand run by chef Mario Barnard (not visible) specializing in using insects in cuisine, in Cape Town. - Mopane worms are a traditional snack in South Africa, but a Cape Town restaurant is set to crawl into the history books as the first to serve a full menu of bug-infused delicacies. Barnard uses mostly dried, ground up worms or pupae, which he sources from people producing them to feed exotic pets. These dried insects are high in protiens, fats, and a variety of minerals, making them very healthy to eat. (Photo by RODGER BOSCH / AFP)        (Photo credit should read RODGER BOSCH/AFP via Getty Images)
Black soldier fly larvae – could they solve the world's food waste problem? (AFP via Getty Images)

Black soldier fly larvae could help to create sustainable animal feed and solve the world’s food waste problem.

Each year humans waste more than one billion tons of food, or a third of all food production.

Many countries are running out of options for disposing of this waste.

Black soldier fly larvae thrive in and around compost piles, where their larvae help break down organic material, from rotten produce to animal remains and manure.

The larvae then commonly grow to about 1,000 times their size, says David Hu, professor in the School of Mechanical Engineering.

"It's like going from the size of a person to the size of a big truck," he explained.

Black soldier fly larvae can eat twice their body mass in food per day – but when these maggots feed while tightly packed in container bins, they generate metabolic heat that collectively can turn lethal for them.

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Georgia Tech researchers found that delivering the right amount of airflow could help solve the overheating issue.

Hungtang Ko, a PhD student in the George W Woodruff School of Mechanical Engineering, said: "Black soldier fly larvae are widely used in an emerging food-recycling industry. The idea is to feed the larvae with food waste and then turn them into chicken feed.

"These larvae make a great candidate for this process because they eat just about everything."

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The researchers placed the larvae in a container subjected to regular air flow at a consistent temperature. They then attached a leaf blower to supply air flow into the chamber, manually ramping up and down the air speed in five-minute trials.

Optimal air velocity will ensure the larvae are cooled off properly and can still feed effectively.

Hu said, "Probing optimal flow velocity will be a good next step. Also, from an engineering perspective, we need to consider other ways that we can cool the larvae down, including using heat transfer.”

The researchers also hope this work will enable black soldier fly larvae to be more readily available as recyclers of food waste, which totals 1.3 billion tons per year, according to the Food and Agriculture Organization of the United Nations.

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Just as important is the potential of these protein-rich insects to reduce the carbon effects of feeding animals.

Global food production contributes more than 17 billion metric tons of human-made greenhouse gas emissions every year, according to a study published in September in Nature Food.

Animal-based foods produce more than twice the emissions of plant-based food, the study found.

Ko said: "There's no sustainable protein source for the animals that we eat. The black soldier fly larvae could play a role in reducing the environmental impact of feeding these animals."

Watch: What would the world be like if humans only ate insects?