Meat may be tasty, but it comes at a hefty price — and I don’t mean at the supermarket. From climate change due to the copious emissions it generates, to forest fires and human rights abuses, the global meat industry has a lot of problems. Plant-based alternatives and high-tech products like cloned meat have been hailed as possible solutions, but there’s an even better alternative that everyone seems to be ignoring at the moment.
It’s easy to see why though because we’re referring to insects. Though Westerners find the notion of insects in their kitchen disturbing and quite disgusting, let alone on their diner table, Marcel Dicke believes this prejudice needs to be cast aside.
Dicke, a researcher at Wageningen University in the Netherlands, just published an opinion paper today breaking down the benefits of insect farming for strengthening our global food security. In the article, the authors not only describe the value of insects as an excellent protein source, but also their role in fertilizing sustainable crops — something that isn’t talked about nearly enough.
“I have a long history in research on insect-plant interactions and microbe-plant-insect interactions, investigating how plants defend themselves against insects, for example by enlisting the enemies of their enemies or by receiving help from root-associated beneficial microbes. Moreover, I have carried out research on the use of insects as food and feed for a decade now,” Dicke told ZME Science.
Insect waste comes in two main forms. There’s the exuviae, or the exoskeletons left behind after molting. Then there’s frass, which basically refers to insect excrement and bits of unconsumed food.
Insect poop is rich in nitrogen, a crucial nutrient that plants require to grow, but is naturally in low abundance in the soil. Meanwhile, the exuviae are rich in chitin, which is typically not edible by most organisms apart from a set of bacteria that have a symbiotic relationship with plants. When the insects molt near plants, the bacteria increase in number helping the plants repel pests.
“When a soil microbiology colleague mentioned that insect exuviae (molted skins) when amended to soil resulted in a stimulation of Bacilli bacteria, that are known to promote plant growth and resilience, we formed an interdisciplinary team, obtained funding, and started investigating the effects of insect-derived soil amendments on plant growth, plant resistance to pests and diseases, plant pollination,” Dicke said.
When combined and added to the soil, the exuviae and frass both promote plant growth and health, acting like a fertilizer-pesticide combo. This means that it could be possible to grow high-yield crops without the need to add artificial fertilizers and pesticides that can be toxic to both humans and the environment. While conventional pesticides are efficient at destroying pests, they do so indiscriminately, also hurting beneficial soil bacteria and critical pollinators like bees.
“The EU has banned several pesticides because of negative effects on the environment. Recent studies on recording pesticides in human bodies are very worrying,” Dicke said.
The researchers envision a closed-loop insect farming circuit whereby insects are grown like livestock, except much more efficiently. While it can take up to 25 kilograms of grass to produce one kilogram of beef, the same amount of grass can produce ten times as much edible insect protein. That’s owed to the fact that insects synthesize protein more efficiently, as well as the fact that 90% of their body mass is edible compared to just 40% for a cow.
Insects could be fed waste streams from conventional crop farming to produce more protein-rich food. The byproducts of insect production, such as the excrements and exoskeletons, can later be used to fertilize more crops, whose activity can be used to feed new insects, closing the loop.
Although insect food sounds repulsive, currently an estimated two billion people in the world already consume insects as part of their diet or as supplements, mostly in Africa and Asia. Insects can also be rich in copper, iron, magnesium, manganese, phosphorus, selenium, and zinc, and are a source of fiber. Insects are also as abundant as they are nutritious.
Insect farming, however, isn’t widespread and in countries where insects are part of the daily diet, they’re mostly collected from forests or farmed in small, family-run establishments for niche markets.
That has to change, thinks Dicke, who has eaten his fair share of crickets, mealworms, and locusts. He and colleagues even published a cookbook with recipes containing insect ingredients. On this front, some forward-thinking companies are developing insect products that are not only nutritious but also tasty. Some are tofu-like other products involving mixing insect meal with sauces or pasta.
“The use of insect residual streams to promote sustainable crop production is a new contribution to designing the agriculture of the future. Such agriculture will be developed with the inclusion of many novel methods/materials and doing so is urgent given the need to produce sufficient food for the growing human population without harming the environment. The production of insects for food or feed is a sustainable activity and by using the residual stream we increase that sustainability,” Dicke concluded.
The paper appeared in the journal Trends in Plant Science.
