The housefly’s love for things like decomposing flesh and blood and its ability to turn this waste into protein is being tapped into to reduce pressure on the overfished seas, feed pigs and chicken – and help save the world.
That you would consider this to be fiction is understandable, for humans generally know flies as enemies which oscillate between filth and human food and spread killer diseases.
But that is because you have not met Jason Drew, or read his book – The story of the fly and how it could save the world.
Drew, born in London, spent two decades as a business leader and entrepreneur only consumed by turning out a profit.
On retirement and relocation to Western Cape, South Africa, however, he changed course and fell in love with the environment and matters of “saving the world” from the dangers posed by human demands.
He remains a businessman but in a different way. Drew says the traditional approach to business that exploits natural resources solely for profit is a danger to the world and that in its place, a new approach that looks to make a profit and guarantee environmental sustainability must be pursued.
And this is where Drew and his colleagues are making use of the housefly to recycle what would otherwise be troublesome waste into feed for fish, pigs and chicken, in – to use his analogy – much the same way used paper is recycled to make new paper.
The book, which Drew co-authored with the science journalist Justine Joseph in 2012, shows how.
Visit to the abattoir
It all started in 2009 in Western Cape when Drew met a slaughterhouse owner who carried him around his premises, allowing him to see the “sea of blood” behind the abattoir with flies buzzing about.
Drew heard from his host that a scientist who was looking to recycle the waste from the abattoir using flies had called on him a week earlier, setting the stage for a meeting between Drew and Dr Elsje Pieterse, head of Animal Nutrition at Stellenbosch University, South Africa.
Drew would spend a year researching and developing the fly rearing business AgriProtein Technologies, together with his brother David Drew and business partners Roy Rudolphe and Duncan Miller.
The business is built on the housefly’s enormous egg-laying ability – it will lay 750 and 800 eggs in a lifespan of just three weeks. The egg will almost immediately hatch into a larva – or maggot – which grows quickly and reaches pupation, ready to turn into a fly, within 72 hours.
“If the conditions are right,” Drew writes, “it (the maggot) will gain over 400 times its weight in these few days.”
It is the maggot which Drew’s business targets. The flies are enticed to lay their eggs into a shed and the hatched maggots shortly stroll down to devour the decomposing waste and fatten.
A few of the eggs will be put on a separate course to grow into adult flies to keep the cycle going, but the majority of the eggs will stop at the maggot stage.
AgriProtein knows the most conducive atmosphere for maggots – about 37 degrees Celsius – and they feed them on rotting blood, fat, intestinal contents and carcasses.
Drew writes of the maggot shed: “If maggots dream of going to heaven, it probably looks like a restaurant garbage can glistering in the sun, or else the AgriProtein Shed.”
“The fattened-up larvae are then dried and milled into a protein-rich, powdery product – a maggotmeal that’s on par with fish meal and nutritionally better than soya,” writes Drew.
Maggotmeal does not sound great, however, so they call it simply Magmeal. But, Drew warns, “it smells better than it should.”