Black soldier flies could help to deal with food waste and provide a feedstock for Scotland’s fish farms, according to a report from Zero Waste Scotland (ZWS).
The fly larvae are voracious eaters and can feed on organic residues from food manufacturing and agriculture, which fattens them up so they become a source of protein for farmed salmon. The larvae can then be processed and used in high-quality salmon feed.
As Scotland’s second biggest food export industry, salmon farming uses huge volumes of feed, much of it sourced from wild-caught fish.
This could be replaced by ingredients from black soldier flies, turning food waste into feedstock. By-products from insect farming could also have potential economic value because they can be processed and turned into biodiesel, chitin and fertiliser.
Michael Lenaghan, environmental policy adviser at ZWS, said: “This is a fascinating and potentially game-changing opportunity. Insect farming is already being embraced in countries across the world.
”With a huge salmon farming sector, Scotland would be well-placed to explore this opportunity, which has the potential to be a green and financially lucrative way of dealing with some of our commercial food waste.
“Of course, there is no single solution to a problem on this scale, and we do not expect insect farming to replace methods such as anaerobic digestion or composting. But with food waste the most carbon-intensive waste source in Scotland, anything we can do to effectively recycle it could make a big contribution to the fight against climate change.”
ZWS’s report estimates that black solider fly treatment of food waste that is generated in the supply chain rather than the household, could generate additional carbon savings and £113 of economic value per tonne of food waste processed.
The report has been produced in advance of a stakeholder workshop to be held in Edinburgh on 7 February 2019 to discuss the opportunities for black soldier fly farming, and other types of insect farming, in Scotland.