Bread: staple or luxury ?
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CTA. 1987. Bread: staple or luxury ?. Spore 9. CTA, Wageningen, The Netherlands.
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The preparation of staple foods in African countries is still a very time-consuming job. This is particularly the case in sub-Saharan countries where millet and sorghum form the basic diet and where most grain is processed by hand. As a result of...
The preparation of staple foods in African countries is still a very time-consuming job. This is particularly the case in sub-Saharan countries where millet and sorghum form the basic diet and where most grain is processed by hand. As a result of expanding urban populations and higher demand for leavened bread and fast foods, wheat requirements have increased considerably in developing countries. In order to promote the use of local grains, the FAO established the Composite Flour Programme in 1964 and started implementation in 1970 by developing methods and products for commercial production in Senegal. Leavened bread made from wheat flour has been used in the Mediterranean for at least three thousand vears. This staple subsequently spread all over the world. The fascination for Western food encouraged the habit of bread consumption in most of the large cities in developing countries. Over the last few decades wheat flour and the American loaf of bread have become familiar products on markets of all continents. Those developing countries influenced by French culture, however, have shown more interest in the consumption of the French 'baguette'. In many developing countries bread is now part of the daily diet of most urban households. Breadmaking has been widely introduced in several African countries. In Kenya, for example, bread consumption has been increasing by 15 % per year since 1978. In some parts of Zaire notably around Kinshasa, bread has virtually replaced the traditional starchy staple 'shikwanga' derived from locally-grown cassava. The popularity of bread encouraged women in several countries to organize baking cooperatives. These efforts were not only in order to produce bread locally but also for making a little extra income. Many of these initiatives have come up against serious problems such as high costs of both transporting flour and fuel for firing the poorly designed ovens. It is true that bread has several advantages over traditional staple foods. It requires no further preparation once purchased and it can be kept for several days in a range of environmental conditions. Moreover, the nutritional value of bread is higher than that of other staple foods such as cassava, rice or potatoes. Nevertheless, bread remains a luxury as far as developing countries are concerned, given the fact that wheat imports and their subsidies are a major drain on local budgets. Wheat accounts for nearly three quarters of all grain imported by African countries. Almost all of Zaire's country's wheat is imported from the American mid-west. For climatic reasons, wheat suitable for breadmaking can be grown in very few countries in tropical areas. Wheat substitutes could be a solution to these problems but many difficulties are encountered in making bread with non-wheat materials. The secret of bread making The main problem is that non-wheat materials do not possess glutenforming protein which, through kneading, gives bread its unique texture and flavour. Only two cereals, wheat and rye, contain this extensible protein. For breadmaking, one requires a flour from a wheat of fairly high gluten content. When the dough is mixed, and subsequently fermented, the protein chains produce a lattice network which holds the carbon dioxide gas released during fermentation. During baking, the carbon dioxide is driven off leaving behind the open crumb texture of leavened bread Making bread by substituting part of the wheat, rather than all of it is not new. The preparation of such composite flours, however, generally demands a more complex processing. Non-wheat materials require dry extraction milling to remove fibre and fat. In times of scarcity, non-wheat materials were generally used to extend bread supplies. In ancient times, barley was frequently added and bread containing a large amount of barley flour was often the staple food of the poor. The use of flour from barley, potatoes, rye and maize occurred throughout the two World Wars. It is important to note that these additives were crops grown in temperate regions. It is known that tropical and subtropical cereals. tuber and root starches have often been added to wheat flour but, unfortunately, there are very few reports about these experiences. More recently, the use of composite flour has become fashionable in the West. This has perhaps helped in reconsidering breadmaking with blends of wheat and non-wheat materials of tropical origin. International efforts for local bread Gluten-free flour has long been used for the preparation of dietetic bread types, especially for patients suffering from coeliac diseases. Going even further, the Dutch Institute for Grain, Flour and Bread Research (TNO), in Wageningen, developed bread made entirely made from non-wheat material. The FAO Composite Flour Programme was designed to effect savings in foreign exchange by reducing wheat imports. Following this initiative, several programmes at the national level have been set up. At the Food Technology Institute (Institut de Technologie Alimentaire, ITA), Dakar, a project was established in 1970 to develop processing techniques for the commercialization of millet products. A similar experience started in Sudan in the late 1970's, with special emphasis on the use of sorghum. The volume of a loaf of bread made with millet flour is generally smaller than that of genuine wheat flour loaf. At the end of the ITA project in Dakar, around 1974, millet bread was produced daily for sale and a commercial bakery was opened. An original method for making French type millet bread, using 30 % millet flour and 70 % wheat flour, was developed by experimental research on the use of millet flour. In 1979 Senegal made it obligatory to use 15 % millet flour and 85 % wheat flour in bread baked in Dakar and the Cape Verde region. By the end of 1982 two commercial mills in Dakar were equipped for millet milling with a capacity of approximately 100 tonnes per day. They produce millet/ wheat flour mixtures following the official requirements for breadmaking Based on the experience in Senegal, a project was launched at the Food Research Centre (FRC) in Khartoum, Sudan, including a sorghum milling and bakery pilot plant. It is interesting to note that another project has been started this year in Burkina Faso to mix wheat with 5 % of maize flour. Insofar as the FRC Sudan project is concerned, a survey showed that bread made with 30 % sorghum flour and 70 % wheat flour was evaluated as palatable to excellent. As with millet bread, the volume of a sorghum loaf remains small and the texture is drier and less elastic. However, it can be kept longer than bread made out of wheat alone. Neither the texture nor the flavour are much affected by the addition of sorghum flour. The capacity of the pilot bakery could reach a maximum of about 15,000 loaves per 24 hours (3,000 kg of flour per day). The distribution of the bread made with up to 25 % sorghum flour was limited to selected clients. Disadvantages of composite flour processing Bread made from composite flour containing low protein materials will require enrichment. Cottonseed flour, fish meal, groundnut and cowpeas are among the products that can be used as protein supplements. Such concentrates should be free from materials which might spoil the flavour, volume and texture of the bread. They should also be free from harmful substances such as gossypol in cottonseed and trypsin inhibitor in soya. Composite flours can also be used for other diverse food commodities. A large percentage of local grains (up to 50 %) can be used in the manufacturing of biscuits and noodles. Non-wheat flours have different milling characteristics. Sorghum and millet flours, for example, have a higher ash and fat content in fine fractions than in coarse fractions, contrary to wheat. The outer layers should be removed by decortication before grinding the endosperm to flour. In Senegal, millet is always decorticated before it is milled. Many consumers dislike the product made by mechanical decortication, so most of the millet in Senegal is decorticated and ground by hand. Specific studies on millet decortication show that dry milling techniques increase the yield by 10-20% compared with traditional pounding; they lighten the workload and also improve flour quality. In Sudan, decorticating sorghum is less cumbersome and in towns most sorghum is ground in stone mills without decortication to produce 100% extraction flours. A fluffy bread texture is difficult to obtain with local cereals. Many years of research have been devoted to this subject, e.g., by the TDRI (Tropical Development and Research Institute) in London, the IDRC (International Development Research Centre) in Canada, by several research institutes in France and by two Belgian universities, the Catholic University of Louvain and the University of Leuven. The latter developed a leavening agent, utilizing pentosan (a rye extract) that raises the dough. Nevertheless, the loaves are still quite different in form from wheat products and also have Inwer nutrient value. Not all sorghum varieties can be used with success in industrial processing. Many popular varieties generally used for traditional dishes are not suitable for mechanical processing due to their softness and the difficulties encountered in separating the bran. The softness of the grain is probably the most important criterion. The consumer prefers a white color and fine flour irrespective of the variety from which it is produced. For efficient production, quality control is essential in purchasing sorghum suitable for milling. White varieties are often mixed with small amounts of coloured kernels, which diminish considerably the quality of the flour. Today deliveries with an impurity rate exceeding 3 % are no longer accepted. New products Traditionally, millet and sorghum are primarily eaten with vegetables and a meat sauce in the form of millet couscous or porridge in several northern and western African countries; sorghum ugi in Kenya or kisra in Sudan. In Sudan, four sorghum mills with a capacity of 150 tonnes per day are producing commodities for traditional dishes. Sorghum flours are more appropriate for producing biscuits and other commodities where the volume is not of prime importance. Snack foods, such as chips, have been developed at the FRC and it was found that they have a good market potential. Research on foodstuffs sometimes lead to new products. Pearl aura is a new polished sorghum product developed at the FRC. It is an attractive ready-to-use cereal, similar to rice, and costs approximately one third as much as rice for the Sudanese consumer. Furthermore, it has a white colour and a good taste. The only disadvantages are the fact that pearl aura requires more water and a longer cooking time than rice. The nutritive value has been estimated to be about the same as rice. Marketing tests suggest that this product may have a promising future. Another example of the use of local varieties for commercial food manufacturing is a project on weaning foods in Benin. Baby food flours which are manufactured in Ouando are made out of locally grown maize, sorghum and soya. Only rice is imported for some products in this project. This semi-industrial manufacturing plant can even be operated manually. The marketing is organized by small traders and the products have been readily accepted by families. Efforts for the future After thirty years of research and development on breadmaking and the use of non-wheat flour compounds, it has become clear that these programmes have not led to concrete results. This is perhaps why projects are now more oriented towards commercial processing of traditional dishes which utilize local grain types. Food emergencies, particularly those involving large numbers of refugees, have become increasingly frequent in recent years. Doubts are still expressed about the impact of food aid, especially its possible detrimental effects on production in the recipient country, its failure to reach the most needy and its influence on food eating habits. The European consumption pattern has also been given too much attention. While focussing research mainly on technical constraints and problems, cultural and economic aspects have been overlooked. Pilot projects conceived to cover demands at national levels were often set-up on too large a scale requiring considerable amounts of local grain necessitating a steady production and reliable quality. Moreover, imported commodities are available at anytime and subsidies make their purchase less expensive. It is cheaper and easier to feed bread to a growing and influential urban population than to increase agricultural production in the countryside and improve transportation and distribution systems. It has to be acknowledged that most of the composite flour breadmaking projects in Africa did not succeed. A report on this subject published by the FAO in 1982 states that :None of these projects actually succeeded in applying large scale flour processing plants over the long term. Most of these research operations did not get beyond the laboratories or pilot installations. The main target of all these efforts was primarily the making of bread. More work is now needed on local dishes and the commercial processing and distribution of ready-to-use traditional food commodities. The first steps in this direction have already been taken in Togo with the support of the French CEEMAT (Study and Experimentation Centre for Agricultural Mechanization) on ready-to-use gari made from cassava. Marketing efforts have already proved successful. If 40 % of the population of sub-Saharan countries alone will be living in urban areas towards the year 2000, precooked traditional food may become very useful. BIBLIOGRAPHY: For further information: - Crabtree J.. James A.W. (1982) 'Composite flour technology: TPl's experience and opinions on the planning and implementation of national programmes', Trop. Sc, 1982, Vol 24(2), pp 77-84. - Miche J C. (1982) 'Realization and consequences of composite flour programmes in the world'. FAO, Rome. - Perten H. (1983)'Practical experience in processing and use of millet and sorghum in Senegal and Sudan'. Cereal Foods World, Nov. 1983, Vol. 28, N° 11, pp 680-683 - FAO/ECA (1985) 'Application of existing techniques'. Economic Commission of Africa, Addis Ababa. Ethiopia.
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