The ethiopian
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INTRODUCTIONInjera, a fluffy honey-comb structured flat bread, is one of the Ethiopian staple foods, mainly prepared from tef (Eragrostis tef) an indigenous cereal grains. It is a popular and nutritious food, with long shelf-life, distinct and preferred characteristics of texture and flavour, and simplest to prepare. Tef grain can be conserved for many years without any appreciable change or damage from insect pests, if vermin and moisture are excluded from storage bins (1). Constraints to tef's increased production and consumption are the high labour input for production and low yield/unit area compared with other cereals. This has led the supply of tef to fall short of demand, and the grain has become the most expensive cereal in Ethiopia. Nevertheless, injera has broad cultural implications for the Ethiopian society and there is always a need to hold on to it (2). Until such a time comes when the supply of tef is increased and thus prices reduced, alternative cereals must be used for the making of injera. though injera can be prepared from other cereals like sorghum, barley, maize and wheat, the acceptance of such a substitute is only limited to certain areas. Thus, it is rational to try to develop a composite flour formula, for injera preparation, which retains the more widely preferred characteristics of the original product and incorporate less expensive ingredients. The objective of the study was to identify and develop a formula for the preparation of a widely acceptable injera. Based on the findings of this study, it was intended to teach local women of the mixture so that they would be able to make it at home, and produce promotional material to popularize the new product. The main question in this research was therefore to find out which cereals to combine and in what proportion, to imitate tef injera in appearance and flavour, as well equate in nutritive value. METHODSThe study was conducted by the Addis Ababa University at the Awassa College of Agriculture, Department of Home Economics. Cereals were bought from a nearby grain marked, preparatory operations were carried out by local women using traditional equipments and the grain was ground into tine powder in a local flour mill. Sixty four mixtures were prepared for baking using tef, wheat, sorghum, barley and maize. A semi-solid dough was prepared by mixing 5 to 6 kilograms of a given flour with luke warm water and kneading it thoroughly for about 30 minutes adding little water at a time. This was then seeded with about 400 ml of starter 'ersho' or wild yeast, and left to ferment for 24-48 hours. Mixtures containing larger proportions of 'tef' were left for longer hours -the maximum is stated in the above mentioned duration of hours. The 'ersho' was a fermented dough of 'tef' .A second fermentation was initiated by the addition of 'absit' (a paste/gel) made by mixing about 500 ml of the fermented dough with about 1500 ml of boiling water and heating it until thickened. A total of 30 pieces of injera were baked on electric-powered flat pan of clay, the 'mitad' and the following tests carried out.
Institute of Development Research P.O.Box 1176, Addis Ababa University Addis Ababa. Visual Observation: Injera samples baked from the 64 types of flour were all examined, and physical resemblance with injera from 'tef' was inspected and those found to be totally different were rejected.
number of eyes 11-15 eyes/cm2 were categorized acceptable. Subjective tests (ie. smoothness of back, texture, elasticity , and reconstitution property) for the initial selection were carried out by the author. Later, taste panellists were involved in carrying out tests on smoothness of back, texture and elasticity, and sensory evaluation. It was not found to be practical to make panellists do reconstitution property . Statistical Analysis: The mean scores of the subjective tests were used as a standard for comparison of results. In the case of number of eyes, 11-15 eyes/cm2 was accepted by basing the observation on practical experience. Cost, Processing Loss and Labour: Samples containing 50% and above of 'tef- the most expensive cereal, or barley -the cereal with the highest processing loss and took the longest time for cleaning were rejected.Sensory evaluation was conducted on those selected.
Note : calculation of price for one injera was basde on the prevailing price of cereals at the time of the research, labour and fuel cost have not been included. Sensory evaluation was conducted on those selected. Table 1 Cost Estimation of One Injera in Birr
Note : calculation of price for one injera was based on the prevailing price of cereals at the tiem of the research, labour and fuel cost have not been included. Table 2: Nutritive Value of Different Cereals in Terms of 100g of Edible portion
Source: Food Composition Table for use in Ethiopia(6).
Table 3: Extent of Acceptance of Injera from different Combinations containing cheaper grains.
1 elasticity 2 Processing 3 Texture 4 Reconstitution 5 Property Sensory Evaluation: The triangle and duo-trio tests were used for panel selection; paired comparison preference and declared control difference tests were employed for sample selection (3,4,5). Fifteen panellists were selected from a predominantly female population including renown cooks, believing that women would be better able to detect slight flavour changes than men. All tasting was done by panellists and scores given according to instructions. The score for each sample was then computed and final comparison made.
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