Abstract

Physicochemical Characterization of Gum of Some Guar (Cyamposis tetragonoloba L. Taup) Lines

Mawada E Yousif, Babiker E Mohamed and Elkhedir AE

The objective of the present investigation was to determine the physical and chemical properties of five guar (Cyamposis tetragonoloba L. Taup) lines, planted in the experimental from of the Faculty of Agriculture, University of Khartoum. The results obtained from all lines studied, GM2, GM6, GM8, GM9 and GM34 were compared those from a known control cultivar, L53. Physical characterization of the guar gum extracted included the determination of pH, relative viscosity, refractive index, solubility and optical density, while the chemical studies involved the determination of the proximate chemical composition of the tested Guar lines namely: moisture, ash, oil, fiber, protein and carbohydrate. The physical properties showed significant differences (P ≤ 0.05) in optical density, solubility and pH among lines and between lines and control, while no significant differences (P ≤ 0.05) were observed in refractive index and viscosity. The thousand-seed weight ranged from 30.21 g-30.75 g, pH 7.16 to 7.40%, relative viscosity 0.1000 to 0.197 cps, refractive index 1.34% to 1.35%, solubility 76.67% to 89.83% and optical density 0.035 to 0.047. The results showed significant differences (P ≤ 0.05) among lines and between lines and control in all physical parameters studied. The moisture content ranged from 8.37% to 8.80%, ash content 3.33% to 4.96%, fat content 1.70% to 2.47%, fiber content 10.53% to 11.83%, protein 25.80% to 30.52%, carbohydrate 43.80% to 48.77%. The results showed significant differences (P ≤ 0.05) among lines and between lines and control in the various levels of guar lines chemical component. All five lines are characterized by possessing physical and chemical properties related to the control sample and to those from previous findings lines GM2 and GM6 proved to possess the best physical and chemical properties a among others and those reported from previous works.