UP till now, our series of articles on soya bean have focussed on its economics and production in the field.
In this article, we look at soya bean as a food crop and highlight issues to do with home processing and utilisation by the local population.
For a long time soya bean has been considered a commercial crop to be harvested and sold to processors who express oil and use the soya cake to manufacture both human and livestock feeds.
Due to limited knowhow on its processing, soya bean earned a reputation for its beany off-flavour which turned away many who attempted to eat it.
Many people consider soya bean to be strictly a cash crop.
The truth is that soya is both a cash and food crop rolled into one.
Given the high levels of malnutrition in both urban and rural communities, soya bean should be widely promoted as a food crop that can be processed and eaten at household level.
As strategy to promote soya bean among small scale and communal farmers, the University of Zimbabwe-led Soya bean Promotion Programme embarked on a soya home processing training programme for mostly rural women.
The strategy was that: ‘The shortest route to a farmer’s heart is through his stomach’!
If farmers appreciated the great taste of soya bean, they would be persuaded to grow it and then enjoy its other multiple benefits.
Most Zimbabweans, farmers and ordinary citizens were unaware that soya bean can be processed into different nutritious dishes at home.
Who would want to grow a crop they cannot eat? For those who tried to use the crop as food, home-made soya-maize meal bread (chimodho) was popular. The ‘beany’ off-flavour (smell) that comes when soya fats come into contact with water, discouraged many from eating soya bean.
After some research, food scientists working with the Soya bean Promotion Programme at UZ developed simple methods of processing soya bean for home use.
The first phase was a ‘Train-the-trainer programme’ in which representatives from pilot groups from all rural provinces across Zimbabwe were taught how to prepare a wide range of soya-based foods and to develop their own recipes based on soya bean.
The trainees returned to their areas to train other women in home processing and utilisation of soya bean. We had learnt that many people were put off by the beany off-flavour from soya bean and were therefore not keen to use it as food. Our food scientists developed ways of removing the anti-nutrition factors in soya bean grain using heat treatment
The reader will be interested to know that raw soya bean contains some chemicals that bind to and inhibit the enzymes that digest proteins in our stomach.
If humans or animals (chickens, cattle, goats) eat raw soya bean, most of it will pass through the gut without being digested. The proteins in the soya bean will not benefit the body.
In some cases, if animals eat too much soya bean grain, they develop bloated stomachs and die when they drink water. This is caused by production of poisonous ammonia from the proteins in the soya grain. Farmers must prevent livestock from eating raw soya bean.
Soya bean also contains some complex sugars that cause flatulence (kufufutirwa).
The trainees in the soya processing course are taught how to remove all these problems so that soya bean can become part of our regular diet.
The training course on home processing teaches participants the methods for removing the anti-nutrition factors using heat treatment.
After the removal of anti-nutrition factors, the course covers issues like processing to produce full fat soya meal. This meal can be used to prepare a wide range of soya-based products and dishes.
Because soya meal is tasteless, it can be added to other foods to increase protein content without changing the taste.
Milk is a rare commodity for the majority of rural families who do not own cattle.
Yet it is an essential dietary item especially for growing children.
Our programme taught rural mothers how to make soy milk using basic equipment and utensils available in most rural homesteads. If each rural family that did not own cattle planted a patch of soya bean, they would literally have their own ‘soy milk cow’.
During training workshops, we encouraged the women to identify various grocery items that could be substituted with soya-based alternatives. We identified up to 17 different grocery substitution products that can be made at home without any special machinery.
Home-made soya foods include soy’ fresh’ and ‘sour’ milk, breakfast porridge, fortified sadza, soya coffee, soya maheu, soya bread, soya cakes, soya muffins, soya butter, soya relishes, soya mutakura, soya maputi and various soya snacks. All these soya-based foods can be garnished to satisfy a wide range of tastes.
Simple processing equipment is used and this includes pestle and mortar (duri nemutswi), sieves of different mesh size with the finest reserved for producing milk quality soy flour, roaster (gango), baking trays, pots and pans.
In the cities, soya chunks have gained popularity. These are produced by processors who use extruders to remove the oil content. The de-fatted soya meal is further processed to produce high protein content soya chunks.
Add to that soya meat substitutes that are used in making samoosas, pies, sausages, minces and the popular soya chunks. Soya chunks can be reconstituted in a variety of ways to create new recipes. The list is virtually endless.
The strategic importance of soya bean for food and nutrition security cannot be over-emphasized. Soil fertility enhancement by soya bean through nitrogen fixation contributes to sustainable cereal crop production, important for the nation’s food needs. Livestock feeds for poultry, pigs, dairy and fish farming add quality proteins to local diets, ensuring healthy life styles.
All families growing soya bean can generate their own milk and meat substitutes, significantly improving diets and literally banishing malnutrition from these communities. When this is coupled with income from sale of surplus soya produce, both hunger and poverty levels can be significantly reduced or even eliminated.
Soya bean has proven immune-boosting properties that have helped HIV/AIDS infected individuals to sustain healthy lives in the face of the pandemic. We have numerous cases where survival of individuals has been sustained through adoption of soya-based diets.
With the current pandemic, adoption and consumption of soya-based foods by the general population will reduce morbidity and lessen the burden on the fiscus. Fewer people will require expensive medication as soyabean-based diets will complement their natural immune systems.
So the case for promoting soya bean among Zimbabwean farmers goes far beyond just import substitution. The crop is of strategic importance from the grassroots all the way to the large scale export sector. Because the local and international markets for soya bean are vibrant, the crop assumes strategic importance. Investments in appropriate research and development of the local soya bean value chain will pay huge dividends to Zimbabwe’s economy.