Soya: wonder plants offer no easy solutions

Soya excites both nutritionists and agronomists alike in that it is an exceptionally rich source of protein and, as a legume, can fix nitrogen. Despite this, the only continent that grows soya seriously as a food crop is Asia. In Africa it is far less important, although it is slowly but surely gaining ground.

Few plants elicit as much enthusiasm as soya, largely because of its remarkable nutritional properties. The beans contain 40% protein and 20% lipids and, once processed, they can be made into an amazing range of edible products: cooking oil, cattle cake, a "milk" whose composition is very similar to semi-skimmed cows' milk, tofu (which resembles "cheese"), beansprouts and, finally, flour which can be mixed with cereal flour. It is even possible to make a minced-meat substitute with textured soya protein. Soya is thought to be the most economical source of protein in the world: one hectare can produce as much as ten hectares given over to cattle grazing.

Widespread adaptability

While nutritionists hail these properties, soya has yet more attributes which are equally admired by agronomists. As a legume it can create its own fertilizer by fixing nitrogen from the air, and it can also adapt to a very wide range of climatic conditions. Highly-advanced varietal research means that soya can now be grown in the humid tropics, in the savannas and in temperate climates.

All this was enough to proclaim soya a wonder plant and a weapon in the war against malnutrition in developing countries. The two largest producers of soya (USA and Brazil) use it mainly to produce oil and cake for cattle-feed for the industrialized countries. Asia, on the other hand, where soya is mainly grown for local consumption, provides less than 20% of the world soya crop - yet it is to the Asian countries that the developing world, especially Africa, looks as an example of the wide range of uses for soya.

Asia has only 0.5% of the area under soya cultivation in the world, though it is not farming methods or conditions that limit its expansion. Although some people claim that it is a demanding crop, a study carried out in Cameroon in 1983 demonstrated that soya necessitates less work that the haricot bean. It may have to be weeded more frequently but harvesting takes half the time.

Winning over consumers

In 1980 Cameroon set up an extension programme to instruct 10,000 resource-poor farmers in the advantages of growing soya. The project was cut short, largely because there were too few consumers to justify it, even though the promoters had taken the trouble to distribute 60,000 copies of a recipe book. But the book used Asian-oriented recipes utilizing beansprouts, milk, tofu and soya flour, which had no appeal to the African housewife. Various experiments in Africa seem to suggest that soya milk will be accepted there only if it is flavoured so as to disguise the beany taste.

Cote d'Ivoire set up a soya project in 1989 in the north-west of the country which will eventually lead to the cultivation of 28,000ha, of which between a quarter and a third will be put down to soya. The main product will be a cooking oil sold under the brand name Primor.

Nigeria currently has more than 200,000ha of soya, the largest area in the whole of Africa. It is farmed extensively, mainly by small farmers, which may account for the low yields (less than 400kg/ha). Despite this, Nigeria's experiments in the use of soya as a food crop offer encouragement. Nigerian women came up with the idea of using the beans to make "Daddawa", a local condiment which is usually made from the seeds of the nere, a leguminous tree from the savanna regions. Soya beans have proved as rich in proteins but more tender, and thus more easy to cook than nere seeds.

This new way of using the soya bean has the advantage of being typically African, and so is more likely to catch on - and endure. lust as encouraging, but more traditional, is the trial with soya milk which has been taking place since 1990 at a privately-owned factory in Lagos. Under the brand name "Uncle Soya", Farina Ltd are marketing flavoured soya milk manufactured from local beans. An annual production capacity of one million litres from 125 tonnes of beans was forecast at the beginning of the project.

Soya may not have enjoyed quite the boom in Africa that some were hoping for, but it is beginning to make its mark locally in places where the processing methods fit in with the traditional patterns of consumption.