African farmers told to plant ‘healthy’ soybean

Farmers in Africa are being encouraged to grow soybean and introduce it to their dining tables to improve nutrition, generate income and boost soil fertility.  

Scientists from Kenya, Malawi, Tanzania and Mozambique — who gathered in Nampula, Mozambique recently — told of the need to diversify local meals and develop new crop recipes.

They said food production in the continent was going down due to climate change, small farm sizes and declining soil fertility.

Mabel Mahasi, a scientist with the Kenya Agricultural Research Institute, said soybean is richer in protein than any other food crop — even meat products — at 40 per cent.

Dr Mahasi said the legume is 20 per cent oil and has all the eight essential amino-acids, making it the healthiest crop.

“But soybean is not well exploited in sub-Saharan Africa, where it is mostly a cash crop,” he said.  

Hailu Tefera, a soybean breeder with the International Institute of Tropical Agriculture, said soybean is a hunger food, an animal feed and an industrial crop.

It also enriches the soil by fixing nitrogen from the air.

Dr Tefera said the crop is very versatile. It can do well in all the maize growing areas of sub-Saharan Africa.  

The scientists are part of a team working on the Tropical Legume II project.

The project has identified five main legumes, and hopes to enhance soybean and cow pea production in areas affected by drought in sub-Saharan Africa.

The project is looking for innovative ways to process and utilise soybean to stimulate production.

It is a collaboration of the International Crops Research Institute for Semi-Arid Tropics, International Institute for Tropical Agriculture, International Centre for Tropical Agriculture, and their national partners.

Fidelis Myaka, a scientist with Ilonga Agricultural Research Institute of Tanzania, said acceptance of foods processed from soybean has increased tremendously.

He said food recipes that utilise soybean fit well into the country’s lifestyle and eating habits.

The recipes include soy milk, soy-blend porridge, weaning foods for children and soy flour.

When mixed with wheat flour, soy flour makes nutritious bread, cookies and mandazis.  

Dr Jonas Chianu of the International Centre for Tropical Agriculture said some farmers in western Kenya are earning money from small-scale processing of soymilk using machines imported from India.

Soymilk has a short shelf life, hence processing of yoghurt is preferred.  

“We introduced the Vita-Goat that process 130 litres of soymilk a day. And now, due to increased demand for soymilk, some groups have purchased a bigger processor, the SoyCow,” said Dr Chianu.  

One of the drawbacks of soybean is that it should not be eaten before processing.

Penina Muoki, a food scientist with IITA in Mozambique, said soybean is the only legume that has to be processed before consumption.  

“Soybean contains anti-nutritional factors such as trypsin inhibitors that stop the absorption of protein in the body,” said Dr Muoki.

Trypsin is the enzyme that digests protein in the body.

He said these anti-nutritional factors are destroyed by high temperatures, such as boiling for 30 minutes, before processing the soymilk or soy flour.

Steven Boahen, an agronomist with IITA, said they are working with farmers to breed soybean varieties with desired traits such as drought tolerance, early maturity, high and stable grain yield, and pest and disease resistance.

“To ensure that seeds of the improved varieties get to farmers at the right time, we are working with community based seed systems,” he said.

Dr Boahen said farmers are growing certified seeds of the improved varieties to sell to other farmers after receiving training on seed production.

He said most private seed companies are not interested in grain legumes because of the low profit margins.

If the seeds are expensive, most farmers will not buy them. They will save some of their harvested crop to use as seeds in the next planting season.  

In Kenya, agronomist are working on a payback system where farmers get 25kgs of seeds and return double that amount to the project.

The seed is then made available to two more farmers, and so on.  

In all the four countries, processors of animal feed and vegetable oil import soybean.

Nigeria is the largest soybean producer in Africa, at over 600,000 tonnes annually, accounting for over 43 per cent of the crop produced in the continent.