Stink bug could boost health and nutrition in Africa

A new study has identified essential nutrients in an edible insect known as stink bug and suggests it as an alternative food source to help meet the dietary demands of an increasing human population.
 
According to the UN Food and Agriculture Organization (FAO), producing 70 per cent more food could help satisfy the estimated 9 billion human population by 2050.

“Our policy recommendation is that carbohydrate-based diets such as cereals and cassava can be fortified with powdered, processed edible stink bugs to improve their nutritional uptake.”

Baldwyn Torto, icipe

Edible insects could contribute to the world’s food security, says Baldwyn Torto, a scientist at the Kenya-based International Centre for Insect Physiology and Ecology (icipe) and a corresponding author of the study.
 
Torto adds that most communities do not know which edible insects are truly nutritional and have beneficial effects on human health.
 
“This is what inspired our research to contribute to food security and income generation among the communities … across the African continent. Some of the traditional foods including insects consumed such as the edible stink bug are highly nutritious and beneficial to human health and should be promoted into mainstream diets,” Torto tells SciDev.Net.
 
The study, published in the PloS ONE journal on 5 January, resulted from funding from the German Academic Exchange Service to aid postdoctoral fellowships in African centres of excellence.
 
“Our policy recommendation is that carbohydrate-based diets such as cereals and cassava can be fortified with powdered, processed edible stink bugs to improve their nutritional uptake,” explained Torto. “We further recommend the creation of a database of all insects consumed across Africa to allow scientists to investigate their nutritional and health benefits and to develop methods for their mass rearing, processing and use to improve nutrition in deficient communities.”
 
Researchers from Kenya and Zimbabwe collected stink bugs — known scientifically as Encosternumdelegorguei — from Jiri Forest in south-eastern Zimbabwe during June 2014 as the period May to August coincides with the insect’s highest abdominal fat composition.
 
The researchers created four harvesting quadrants that covered the entire forest. In each quadrant, they harvested the stink bug from branches of ten randomly selected trees. The researchers searched for chemical components such as antioxidants, amino acids, essential fatty acids and toxins.
 
“We found high protein, fatty acids and anti-inflammatory chemicals such as flavonoids content,” says Torto, adding that the edible stink bug has the potential to help lessen nutrient-deficient communities in Africa where vegetables and animal sources may be limited.
 
The researchers identified seven essential fatty acids for human nutrition and health out of the ten they found, four flavonoids and 12 amino acids, including two considered to be the most limiting in cereal-based diets.
 
But Torto warns that like other food sources such as cereals and vegetables, harvesting and processing of the stink bugs require use of appropriate storage procedures to avoid contamination with poisonous moulds which produce chemicals such as aflatoxins known to negatively affect human health.

Stacia Nordin, agriculture and nutrition education specialist for the USAID (United States Agency for International Development) Feed the Future project in Malawi, concurs with the observation that edible insects are often a source of high-quality source of proteins, fats, vitamins and minerals, with the potential to improve nutrition.
 
Nordin adds: “Food safety is paramount from production through processing, storage and consumption. Malawi has a great number of natural resources that should be valued, studied, protected and utilised for nutrition, environmental health and income.”
 
This piece was produced by SciDev.Net’s Sub-Saharan Africa English desk.