Physico-Chemical Properties of Teff [Eragrostis tef (ZUCC.) Trotter] Grains and Their Utilization in Bread and Biscuits Making

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Date
2007
Authors
Mariam Idreis Osman Mohammed
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Publisher
University of khartoum
Abstract
Teff grains [Eragrostis teff (ZUCC.)Trotter.], and two types of Australian wheat flours (all purpose and special flours) were used in this study. Proximate analysis, hectoliter weight and thousand kernels weight were carried out for teff grains. Minerals content, bioavailability of total minerals, amino acids profile and lysine content, and anti-nutritional factors were investigated for teff grains. All these parameters were carried to evaluate the nutritional value of these grains. The results showed that the thousand kernels weight of teff grains were (0.43 g/1000kernel) and hectoliter weight was (84.9Kg/hectoliter). The protein content of teff grains flour was 10.03%, crude fiber 3.65%, ash content 2.57% and fat content 4.56% (as dry matter),but the moisture content of teff flour was 8.67%. It is observed that teff grains flour has (333.6 mg polyphenols/100g), (536.12 mg phytic acid/100g) and (0.6 mg tannin/100g). The results of total minerals and their availability showed that teff grains flour is a good source of the minerals (1813 mg P /100g) and availability 24.159% ,(0.768 mg Cu /100g) and availability 73.997%, (229.917mg Mg/100g) and availability 34.59% and (44.319 mg Fe/100g) with availability 2.89% .While the result of amino acids showed that the Lysine content of teff grains flour was (5.6 g/100g protein), Histidine (6.4g/100 g protein), Leucine (18.3 g/100 g protein) and Valine (16.6 g/100 g protein), thus teff flour is a good source of amino acids specially lysine (most limited amino acid in cereals). The chemical analysis of prepared flour blends(5,10,15 and 20%teff flour in bread flour and 25,50,75,100% teff flour in biscuits flour) and the control(all-purpose and special flours),showed significant decrease (P=603;0.05)in their moisture content and their protein content, while the protein content of bread flour blends showed no significant difference (P=603;0.05) among the samples.The results of the flour blends, 5,10,15and 20% teff flour in bread flour and 25,50,75and 100% teff flour in biscuits flour)showed significant increase (P=603;0.05)in their ash content . The results of farinograph showed that the water absorption of bread flours and their blends were increased, but the development time of the doughs gave the same values (5.3min.), except 20% teff flour which gave the lowest value. The results of farinograph showed that the water absorption and development time of biscuits flours and their blends were decreased ; except 75% of teff flour gave the highest values on their development time (17.0 min).The results of gluten quality and quantity of biscuits and bread flours and their blendes, showed significant deterioration (P=603;0.05). Five percent teff flour bread showed significant increase (P=603;0.05) in specific loaf volume while 25% teff flour biscuits showed significant decrease (P=603;0.05) in spread ratio. Five percent teff flour bread gained the highest score of over all acceptance by panelists, whereas 25and 50% teff flour biscuits gained the highest score of over all acceptance by the panelists
Description
Dissertation submitted to the University of Khartoum in partial fulfillment of the requirements for the Degree of Master of Science in Food Science and Technology
Keywords
Physico-Chemical Properties [Eragrostis tef (ZUCC.) Trotter] Bread Making Biscuits Making Food Science and Technology University of Khartoum
Citation
Mariam Idreis Osman Mohammed, Physico-Chemical Properties of Teff [Eragrostis tef (ZUCC.) Trotter] Grains and Their Utilization in Bread and Biscuits Making. – Khartoum : University of Khartoum, 2007. - 129 P. : illus., 28 cm., M.Sc.