Caterpillar farms: Growing the food of the future?

Two scientists and an entrepreneur are crunching the science behind edible caterpillars to help fight malnutrition and food security problems in West Africa.

For most people the idea of chewing on a caterpillar or tucking in to a tarantula is pretty unpalatable, to put it mildly. Yet according to the United Nations, some two billion people around the world consume insects regularly. This prompted World Service listener Saman from Pakistan to ask the BBC CrowdScience team "are insects a serious food source?"

In order to tackle this question the programme team headed out to Burkina Faso in West Africa, where shea caterpillars are an important part of the local diet in a country where over 30% of children suffer from chronic malnutrition and 2.7 million people are at risk for food insecurity.

Shea caterpillars contain high levels of protein and micronutrients

Caterpillar enthusiast Charlotte Payne is a PhD student at Cambridge University. She is currently conducting research on the caterpillar lifecycle in partnership with entomologists Prof Antoine Sanon and Dr Athanase Badolo of the University of Ouagadougou.

"Shea caterpillars have the potential to help people break out of a cycle of poverty," she exclaims when we met her on a farm in the rural village of Soumousso in the West of Burkina Faso.

At the moment the caterpillars are only available for a few weeks a year. But with their high levels of protein and micronutrients like iron and zinc, they have the potential to fend off "hidden hunger", as micronutrient deficiency is sometimes called, and change the financial situation of the poorest people in West Africa, especially women and children.

Caterpillars can be cooked whole or turned into products, such as protein bars or croquettes

How to breed caterpillars

Together with her colleague Darja Dobermann, a PhD student at the University of Nottingham and Rothamsted Research, Charlotte is trying to crack the science behind shea caterpillars and make them available all year round.

"In the same way they keep chickens in their backyard, the women would be able to keep caterpillars too," Charlotte explains.

While in Burkina Faso, Charlotte is collecting as much information as she can about the needs and wants of the local people. Her preliminary results suggest that breeding caterpillars would be very welcome in the region. "It would be great if I could rear the caterpillars all year round because I would have enough to eat and earn a lot of money selling them," one woman in Soumousso told us.

Once processed and packaged, shea caterpillars stay edible for up to 18 months

To help accomplish this vision there are many hurdles that the researchers must overcome. For starters the caterpillars are fussy customers. They only feed on the leaves of the shea trees.

Similar to how scientists have spent years working out what the best feed for livestock is, Darja explains, the same needs to happen for the caterpillars. From an environmental point of view it is of some consequence how these caterpillars are fed.

Environmentally savoury

Insects are often touted as a panacea for the environmental problems that come with producing meat, because they emit less greenhouse gasses and take up less space.

"The unfortunate thing is that the majority of insects that are commercially farmed are predominantly fed with chicken feed. Chicken feed is made out of soy and this isn't very sustainable. Unless you can get the insects onto a waste product as their food source, they aren't more sustainable than chickens from an environmental perspective," Darja explains.

We investigated caterpillar farms after Saman from Pakistan asked us: "Are insects a serious food source?" If you've got a science question you want BBC CrowdScience to look into, get in touch via the form below and we'll investigate a selection.

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In her lab in England, Darja will be analysing shea tree leaves to uncover why the caterpillars like them so much. This includes figuring out what nutrients the caterpillars are getting from the leaves and discovering whether the leaves send out a special "smell" - volatile aromatic compounds - that the caterpillars are drawn to.

"There might be something particularly appealing about these leaves that we could synthesise and spray onto artificial feed to attract the caterpillars," Darja explains.

Charlotte and Darja are not alone in their quest to turn caterpillars into a sustainable food source. They work closely with local entrepreneur, Kahitouo Hien, who is betting all on the success of these nutritious critters.

Caterpillar cook-out

Outside Kahitouo's factory in the capital Ouagadougou a huge caldron filled with thousands of caterpillars is bubbling and filling the air with a pungent aroma. With his business, FasoPro, Kahitouo is trying to create an industry for shea caterpillars. Something that no-one else has dared do before.

Today he sells 10 tonnes of caterpillars every year to markets and shops around the country. But it has not been easy to get to this point.

"A lot of people laugh when they hear about my business," Kahitouo explains as he leads us into a room filled from top to bottom with tightly packed boxes of dried caterpillars.

Even though caterpillars are traditionally eaten in Burkina Faso, Kahitouo has had a hard time convincing the community that they should eat more of them.

"In the beginning it was very difficult for me to find even one shop that would sell the product, but now I don't even have to leave my office. The shops call me up. When I think about that I feel really proud of myself and the business."

Kahitouo hopes to spread the business model to other countries but using the local insects found in each place.

Bugs to the rescue?

With nine billion people in the world by 2050 and food production needing to increase by 70% according to the UN, we may all have to get used to the taste of bugs like many people in Burkina Faso already have.

Indeed, there is scope for edible insects to play a serious role in food culture beyond being a fashionable snack.

However working out how to farm them in an environmentally friendly way is a question that continues to bug.

BBC CrowdScience, Should We Eat Insects? airs on the World Service at 19:32 GMT on the 7th of April 2017. After this you can listen online or download the podcast.