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RESULTS

Visual observation showed that 10 of the 64 baked products did not resemble injera as known traditionally or were too fragile or sticky. Of the remaining 54 samples, 14 scored a mean of 3.5 or above in the subjective tests with the number of eyes ranging from 11 to 15 eyes/cm2, and were accepted. After considering cost, processing loss and labour, 6 samples were selected from the 14. Paired comparison preference test was conducted introducing 2 samples at a time, and those underlined are the samples preferred.
a. 1. Tef 25% Sor"hum (k) 50% Wheat 25%

2. Tef 25% Sorghum (k) 50% Barley 25%

b. 3. Tef 25% Barley 25% Sorghum (k) 25% Maize 25%

4. Tef25% Wheat 25% Sorghum (k) 25% Maize 25%

c. 5. Tef 34% Wheat 33% Sorghum (t) 33%

6. Tef 35% Wheat 25% Sorghum (k) 40%

Key: Sorghum Vulgare feterita troup Sorghum Vulgare kafir troup

Finally,declared-control-differencetest was conducted using tef as the standard, and comparing each of the selected samples with tef, and the following scores were give: 5 = same as standard; 4=slightly different from

standard; 3 =moderately different from standard; 2 =very different from standard; 1 = extremely different from standard; The scores for the three samples were: (1) tef 25% + wheat 25% + sorghum (k) 25% + maize 25% = 3.00; (2) tef 25% + wheat 25% + sorghum (k) 50% = 3.41; .(3) tef 35% + wheat 25% + sorghum (k) 40% =3.66.
Therefore, the sample consisting of tef 35% + wheat 25% + sorghum (k) 40%, was found to be the best of the three. The two highest scores went for tef, wheat, and sorghum (k) combinations.
Cost of One Injera: Table 1 shows the average price of cereals, processing loss, yield of injera per kilogram of flour, and in the last column, the price of one injera for each cereal grain and the composite flour. Comparison of the price of tef injera with that of the composite flour shows that there is a difference of Birr, 0.04 (4 cents) for each injera, a cost reduction of about 27% .
Nutritive values were calculated using data from food composition table for use in Ethiopia (6), and the new product equated tef,(Table 2).

DISCLSSION

Composite flour development had also been tried by other researchers and the results recorded were satisfactory but the parameters used were not shown. At the Institute of Agricultural Research (IAR), Agro-

engineering, Home Economics and Food Technology Department (7) 1: 1 mixtures of cereals were developed. Tef/pulse combinations in the ratio of 3: 1 also showed satisfactory results, except in the cases of

lentils and mung beans. No report was available on a research done at the Ethiopian Nutrition Institute combining tef and Sorghum vulgare kafir group (8). The use of fermented dough of tef for a starter and hence the involvement of the same types of microorganisms in all samples at the initial stage of the fermentation process, did not cause any problems with any of the flours. In the fermentation of 'tef dough, the engagement of two groups of microorganisms have been identified by other researchers. The groups were those that belong to the genera Saccharomyces and Torulopsis (9), gram negative aerogenic rods and Bacillus Suptilis ,

lactic acid bacteria and yeast (10); and Enterobacteriaceae (11).

The cheapest composite flour would have been that incorporating a high proportion of maize followed by sorghum. Results however showed that, of the 64 combinations, those containing a higher proportion of maize were rejected at the initial stage of the investigation (Table 3).
Since data on storage loss of the different cereal grains were not available, it has not been possible to consider this important parameter in the study. Tef is known for its storage stability and thus the price reduction achieved may not have importance. If that is the case, the long term solution would lie in the attempt to improve the yield per unit area of the tef grain.

ACKNOWLEDGEMENTS

The author is grateful to Dr. Geremew Haile and Dr. Aregay Waktola of Addis Ababa University for their invaluable consultation services, her colleagues Firdu Azerefegn and Asfaw Mesfin for a limitless assistance.

Special thanks goes to the Food Policy and Nutrition Division of the UN's Food and Agriculture Organization (F AO) for financing the project.

REFERENCES

1.Tedesse Ebbs. Tef, the cultivation, usage, and some of the known disesses and insect pests. Experiment Station Bulletin Haile Selassie I University, College of Agriculture, 1969;Vol.6024-26.

2.Hsregewoin Cherinet. "Injers" An Ethiopian National Food, 1984; Unpublished.

3.Amerine M.A., Pangborn, R.M. , Roessler, E.B.

Principles of Sensory Evaluation of Foods. Academic Press, New York, USA, 1965.

4.Smith G.L. Statistical Properties of Simple Sensory Difference Tests. Confidence Limits and Significance Tests J.Sci. Food Agric, 1981; 32: 513-520.

5.Piggon, J.R (Ed). Sensory Analysis of Foods Elsevier Applied Science. London, 1984.

6.Ethiopian Nutrition Institute. Food Composition Table for Use in Ethiopia. 1969; Vol:I.

7.Institute of Agricultures Research Progress Report for the period April 1977 to March 1978 Utilization Studies Agro-Engineering. Home Economic. and Food Technology Department, 1979.

8.Personal Communication

9.Chaltu Gifawessen, Abrsham Biorat. Yeast Flora of Fermenting Tef (Eragrostis tel) Dough. Sinet: Ethiopian Journal of Science 1982; 5.(1) 21-25.

10.Berhanu Abegaz Gashe, Meaza Girma, Abrsham Biorst. The role of Microorganisms in Fermentation and their Effect on Nitrogen Content of Tef. Sinet. Ethiopian Journal of Science, 1982; 5.(2) 69-76.

11.Berhanu Abegaz Gashe. Involvement of Lactic Acid Bacteria in the Fermentation of Tef Eragrosis tef an Ethiopian Fermented food. Journal of Food Science, 1985; 50:(3) 800- 801.

THE EFFECT OF SOAKING TIME AND SOAKING SOLUTION

ON THE NUTRITIONAL QUALITY OF GRASS PEA SEEDS

Kelbessa Urga MSc. and Mengislu Gebretsadik:
ABSTRACT: The effect of soaking time and soaking solution on the nutritional quality of grass pea seeds were studied. The soaking solutions used were:plain water (pH 7.3); ImM HCl (pH 3.0); ImM NaOH solution (pH 11.0) and 0.1% (w/v) wood ash solution (pH 12.0). Mature whole grass pea seeds soaked for 72 hr in the four soak media that were used resulted in total solids loss of 1.3, 1.2, 5.2 and 6.2 percent, respectively. Total protein content increased by 11 and 13 percent, respectively for seeds soaked for 72 hr in plain water and ImM HCl. In contrast, a total protein loss of 12 and 16 percent, respectively was noted in seeds soaked for 72 hr in ImM NaOH solution and 0.1% wood ash solution. The soaking process resulted in the loss of non protein nitrogen, total soluble sugars and reducing sugars. Soaking also influenced the ash and crude fibre contents of the seeds. The pH of the soaking solutions were also altered in accordance to the soaking process. However 'kikn' showed significantly lower nutrient retention values compared to the whole seeds mainly due to the higher loss of solids during soaking. [Ethiop. J. Health Dev. 1993;7(2):79-83]

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