Technology

Maggot Power

 By Robin Wylie

Scientists from the USA have found that high quality biodiesel can potentially be created using the larva of flies (maggots). The biodiesel potential of the oil was due to the high concentration of medium chain saturated fatty acids and low concentration of polyunsaturated fatty acids that it contained…

(Cover Photo  by protaculturemedia.tumblr.com)

The fat-rich larvae of a common fly can be used to produce high-quality biodiesel, a new study suggests. Researchers in Hawaii grew larvae of the black soldier fly (above) on food waste for approximately two weeks. They then collected the larva before drying them and separating the remains into their oil and protein constituents.

The team found that the oil obtained from the dried larvae had a composition ideal for producing biodiesel. The oil was rich in “medium chain saturated fatty acids,” compounds which, when chemically reacted with alcohol, produce low viscosity, highly stable biodiesel.

Their results appear in the journal Renewable Energy.

The majority of today’s biodiesel is produced using oil derived from plants — commonly soybean, sunflower and palm — also using the reaction with alcohol. However using such sources can create competition with the agriculture industry, potentially inflating the price of biodiesel.

Image: John Tann / Flickr CC BY

But by using oil derived from larvae to produce biodiesel instead, the fuel could be produced using only organic waste as the feedstock — this would remove the need to use agricultural land and accordingly could make the production of biodiesel simpler and cheaper.

As well as producing biofuel-friendly oil, black soldier fly larvae can consume between 40 and 70 percent of the organic waste on which they feed. The larvae of this fly are especially voracious eaters; since the adults do not eat during their 5-8 day lifespan, their larvae need to seriously bulk up before pupating.

The fly larvae were fed on mixed food waste from cafeterias in Hawaii and South Carolina. After gorging themselves, black fly larvae instinctively migrate towards a dry area in order to pupate into adult flies. This tendency allowed the researchers to easily collect the larvae just before maturation, and subsequently collect their biofuel-friendly fats.

about the author
Robin Wylie
Freelance earth/space science journalist. Currently finishing off a PhD in volcanology at University College London.