The Effect of Various Factors on the Emulsifying Stability of Gums- a Comparative Study

Elgaili. A. Omer; M. E. Abdulaziz; M. E. Osman

Elgaili. A. Omer Deanship of Graduate Studies and Scientific Research, Kassala University, P.O.Box 266, Kassala. Sudan
M. E. Abdulaziz Department of chemistry, Faculty of Science, Sudan University of Science &Technology Khartoum, Sudan
M. E. Osman The Gum Arabic Company Ltd, P.O Box 857, Khartoum, Sudan

Abstract

Emulsifying stability of Acacia polyacantha gum has been

studied in comparison with other Acacia species, such as A.

senegal and A seyal.It could be concluded that addition of protein

improved the emulsifying stability of the gum. Increasing of

concentration (0.05% to 0.4%) increases the emulsifying stability

of all the three gums. Blend of A. polyacantha and A. seyal that

contain 25% A. polyacantha and 75% A. seyal was found to

possess superior properties (1.04) compared to parent polyacantha

gum (0.97). It has been demonstrated that the high molecular

weight protein rich fraction of the gum is preferentially adsorbed

to the oil phase during emulsification process. The emulsifying

stability of divalent ions was high for calcium polyacanthate,

calcium senegalate and calcium seyalate, while that of

monovalent ions was low for sodium polyacanthate, sodium

senegalate and sodium seyalate. It was clear that with increase in

PH values up to (9), the emulsifying stability decreases (0.95),

increasing the time of stirring (l — 5min), it increased the

emulsifying stability (0.93 to 1.03). The rise in temperature

(450C- 850C) (0.99 0.76) resulted in declining the emulsifying

stability of the gum.

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