From flies to food
In less than three decades an additional two billion people will require sources of high-quality food, presenting a global food security challenge.
In less than three decades an additional two billion people will require sources of high-quality food, presenting a global food security challenge. Rising demand for sources of animal-derived protein (e.g. fish, meat and eggs) is an area of particular concern, with a deficit of at least 60 million tonnes projected by 2050.
However, animal protein production has a significant caveat, in that animals are reliant upon protein sources (e.g. soybean meal and fishmeal) in their feed. Ever-increasing demand for animal-based protein (by humans) will continue to stimulate demand for these feed sources, which are both unsustainable and diminishing in supply.
Black Soldier Fly larvae are a highly promising replacement protein source for livestock and fish. They are ideal to farm as they exhibit exceptional growth rates, population densities and reproduction rates. Black Soldier Fly larvae production requires 96% less land area, 95% less water and emits 96% less greenhouse gas than equivalent soybean production. They are able to metabolise a wide range of vegetable matter, which when farmed, facilitates the transformation of food waste into high-quality protein sources. Importantly, Black Soldier Fly larvae have a protein content comparable to soybean meal and fishmeal and an essential amino acid profile suitable for poultry and fish. This enables the direct replacement or substitution of soybean meal and/or fishmeal with Black Soldier Fly larvae for insect meal in feed formulations.
In general, Black Soldier Fly larvae production companies use food waste to rear their larvae. However, under EU legislation, BSFL may only be reared on pre-consumer food waste (e.g. fruit and vegetables). Furthermore, food waste is highly geographically dispersed, and exhibits inconsistent compositions and supply volumes, as it is subject to significant seasonal and annual variation. This approach is considered unsustainable, as the volumes of suitable food waste are insufficient to fuel market demand for Black Soldier Fly larvae going forward.
To address this major challenge, Professor Neil Bruce and his team at the Centre for Novel Agricultural Products (CNAP) have developed a novel biological process to transform agricultural residues into feed for Black Soldier Fly larvae
Agricultural residues, such as wheat straw and rice straw, composed of lignocellulose, are potentially excellent candidates as fly food. They are available in high localised abundances, overcoming issues of supply chain security and production scale limitations. They are highly defined feedstocks that exhibit little variation within/between crops and growing seasons, better ensuring reproducibility in quality and yield.
They are also of easily identifiable origin, improving supply chain transparency over current heterogenous food waste. Therefore, agricultural residues have the potential to mitigate many of the shortcomings associated with food waste, though until now no technology exists to transform them into food for Black Soldier Fly larvae.
The patented technology developed at CNAP exploits the ability of microbes to digest agricultural residues, developing a biological method to release its sugars and nutrients while adding nitrogen in the form of microbial protein to make a palatable and nutritious feed for Black Soldier Fly larvae Black Soldier Fly larvae. Prof Bruce has recently been awarded a BBSRC Follow-on Fund grant, in partnership with Fera Science Ltd, to optimise the process to convert agricultural residues into a defined, sustainable feedstock, and to demonstrate its economic and environmental potential.
Professor Neil Bruce is a microbiologist and Director of CNAP. His research is focussed on discovering new enzymes with industrial and environmental applications.