Emulsion-Stabilizing Effect of Gum from Acacia senegal (L) Willd. The Role of Quality and Grade of Gum, Oil Type, Temperature, Stirring Time and Concentration

Murwan K. Sabah El - Kheir, Abu El Gasim A. Yagoub and Asma A. Abu Baker

Gum Arabic (Acacia senegal ) from Kordofan (Central Sudan) and Damazin (Blue Nile, Western Sudan) were used in this study. Physicochemical properties of gum samples were studied (moisture, ash, nitrogen, total soluble fiber, specific rotation, relative viscosity, refractive index and pH). Results show significant differences in moisture content, protein content and relative viscosity between Kordofan and Damazin gums. Damazin gum contained higher protein (3%) and characterized by higher viscosity (24.81) compared to Kordofan gum. Stability of Acacia gum emulsion in regard to type of refined oil (sesame, groundnut, cotton seed, sunflower and corn), temperature, stirring time, concentration and gum grade was also investigated. Results revealed that emulsion stability is significantly affected by the type of oil used. Cotton seed oil gave the most stable emulsion while groundnut resulted in the lowest stable emulsion. Increase in the length of the stirring time is significantly increased stability of the emulsion. Also emulsion stability was affected by gum grades. Other factors of concentration and temperature did not significantly influence emulsion stability.