Abstract:
The physiochemical properties of Acacia Senegal and Acacia nubica (new
name A. oerfota) gums were studied. They include; moisture, ash, nitrogen hence
the protein, solubility test, tannin content, total soluble fiber, intrinsic viscosity,
specific optical rotation, the pH value, acid equivalent weight and accordingly the
uronic acid. The molecular weight of the samples was estimated using osmotic
pressure measurment.
The value of number average molecular weight (M n) of A. nubica was
found to be 4.4. The high molecular weight and, high water solubility suggest a
highly branched structure; (the molecular weight of A. senegal is 2.2).
The cationic composition of Acacia nubica was determined and the result
showed that Calcium was the most abundant cation in the samples (17.691 ppm)
followed by Potassium (10.917 ppm), Magnesium (6.099 ppm), Sodium (5.818
ppm), Manganese ( 0.161 ppm), Lead (0.0883 ppm), Iron (0.0752ppm), and
Copper ( 0.0135ppm).
Emulsification studies show that Acacia gums (A. nubica, A. senegal)
possess good emulsifying activities and stability, however the emulsifying stability
of the emulsion of nubica gum is less than that of A. senegal gum. Blends of
Acacia nubica with Acacia senegal were investigated and it was found that a
mixture containing 50% A. nubica: 50% A. senegal produced blends having better
emulsifying stability compared to other blends of gums.
