Nutritional Evaluation of Sorghum Flour (Sorghumbicolor L. Moench) During Processing of Injera

Authors: Noha A. Mohammed, Isam A. Mohamed Ahmed, Elfadil E. Babiker

Abstract:

The present study was carried out to evaluate the nutritional value of sorghum flour during processing of injera (unleavened thick bread). The proximate composition of sorghum flour before and after fermentation and that of injera was determined. Compared to the raw flour and fermented one, injera had low protein (11.55%), ash (1.57%) and fat (2.40%) contents but high in fiber content. Moreover, injera was found to have significantly (P ≤ 0.05) higher energy (389.08 Kcal/100g) compared to raw and fermented sorghum flour. Injera contained lower levels of anti-nutritional factors (polyphenols, phytate and tannins) compared to raw and fermented sorghum. Also it was found to be rich in Ca (4.75mg/100g), Fe (3.95 mg/100g), and Cu (0.7 mg/100g) compared to that of raw and fermented flour. Moreover, both the extractable minerals and protein digestibility were high for injera due to low amount of anti-nutrients. Injera was found to contain an appreciable amount of amino acids except arginine and tyrosine.

Keywords: Cooking, Fermentation, Malt, Protein fractions, Sorghum.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1083235

References:

[1] Miller, E. (1996). Minerals. In: food chemistry chapter 4(O.R. Fennema, ed.). Marcel Dekker Inc. New York. Basel. Hong Kong.
[2] Murty, D. S. and Renard, C.( 2001). Sorghum. In crops in tropical Africa. Raemaekers, R. H (ed.). pp 68-96. Brussels. Belgium.
[3] Dirar, H.A. (1991). The Indigenous Fermented Foods and Beverages of Sudan. In: Applications of Biotechnology to Food Processing in Africa. Selected Paper. UNIDO, Vienna. 23-40.
[4] Chavan, J. K., and Kadam, S. S. (1989). Critical reviews in food science and nutrition. Food Science, 28, 348-400.
[5] Oda, M., Hasegawa, H., Komatsu, S., Jambe, M., and Tsuchiya, F.(1983). Antitumour polysaccharide from Lactobacillus sp. Agric. Biol. Chem., 47, 1623-1625.
[6] Umeta, M. (2004).studies on the fermentation of tef (Eragrostis tef) and its nutritional significance. M. sc. Thesis, School of Biological Sciences, University of East Anglia, Norwich.
[7] Kebede, Y., Menkir, A. (1984). Research activities of the Ethiopian sorghum improvement programme. In Proceeding of the Third Workshop on Sorghum and Millet Improvement in Eastern Africa, Morogoro, Tanzania, pp. 73-97.
[8] Zegeye, A. (1997). Acceptability if injera with stewed chicken. Food Quality and Preference, 8, 293-295.
[9] AOAC (1990). Official methods of analysis, 15th edition. Association of Official Agricultural Chemists, Washington D. C.
[10] AACC (2000). Approved methods of American Association of Cereal Chemists, 10th ed., vol. 11(Ed), St Paul M. N. USA.
[11] Osborne, D.R. and P. Voogt (1978). Calculation of caloric value. In: Analysis of nutrients in foods. New York, Academic Press, pp: 23-34.
[12] Wheeler, E. L. and Ferrel, R. E. (1971). A method for phytic acid determination in wheat and wheat fractions. Cereal Chem., 48,312-317.
[13] Price, M. L. and Butler, L. G. (1977). Rapid Visual Estimation and Spectrophotometer Determination of Tannin content of sorghum grain. J. Agric. Food Chem., 25: 1268-1273.
[14] Price, M. L.; Van scoyoc, S. and Butler, L. G. (1978). A critical evaluation of the vanillin reactions as an assay for tannin in sorghum grain. J. Agric. Food Chem. (26), 1214.
[15] Chapman, H. D. and Pratt, F. P. (1982). Methods of analysis soils plant and water, university of California, Agriculture Division, USA, pp.169.
[16] Chauhan, B.M. & Mahjan, L. (1988). Effect of natural fermentation on the extractability of minerals from pearl millet flour. J. Food Science, 53, 1576-1577.
[17] Saunders, R. M, Connor, M. A. , Booth, A. N. , Bickoff, E. N. and Kohler, C. O. (1973). Measurement of digestibility of alfa alfa protein concentrate by in vitro methods. J. Nutrition, 103, 530-535.
[18] Snedecor, G. W., & Cochran, W. G. (1987). Statistical Methods (P. 221- 222) (17th ed.). Ames. 1A: The Iowa State University Press.
[19] Ibrahim Fatima S., Babiker E. E., Nabila E. Yousif and Abdullahi H. ELTinay (2005). Effect of fermentation on biochemical and sensory characteristics of sorghum flour supplemented with whey protein. Food Chem., 92, 285-292.
[20] Gebrekidan, B.,GebreHiwat, B. (1982). Sorghum injera: preparation and quality parameters. In ICRISAT, Proceedings of International Symposium on Sorghum Grain Quality , Patancheru, India, pp. 55-56.
[21] Eggum,B. O.; Monawar, L.; Back Knudsen, K. E., Munck, L. and Axtel, J. (1983). Nutritional quality of sorghum and sorghum foods from Sudan. J. Cereal Science, 1:127-137.
[22] Idris Wisal H., Samia M. AbdelRahman, Hagir B. ELMaki, Babiker E. E. and Abdullahi H. EL Tinay (2005). Effect of germination, fermentation and cooking on phytic acid and tannin contents and HClextractability of minerals of sorghum (Sorghum biocolor) cultivars. J. Food Technol., 3 (3), 410-416.
[23] El Khalifa, A. O., & El Tinay, A. H. (1994). Effect of fermentation on protein fractions and tannin content of low- and high-tannin cultivars of sorghum. Food Chem., 49, 265-269.
[24] Urga, K., Fite, A.,and Biratu, E. (1997). Effect of natural fermentation on nutritional and anti nutritional factors of tef (Eragrostis tef). Ethiopian Journal of Health Development 11, 61-66.
[25] Osman, M. A. (2004). Changes in sorghum enzyme inhibitors, phytic acid, tannins and in vitro protein digestibility occurring during Khamir (local bread) fermentation. Food Chem., 88, 129-134.
[26] Mamiro, P.R.S. Vancamp, J. Mwikya, S. M. and Huyghebaert,A. ( 2001). In vitro extractability of calcium, iron and zinc in finger millet and kidney beans during processing. J. Food Sci. 66, 1271-1275.