The characterization of four proteinaceous Acacia gums which are not permitted food additives

The gum exudates from Acacia fischeri, A. kamerunensis, A. spirocarpa and A. stenocarpa (all African species from Bentham's Section Gummiferae) have been completely characterized in terms of their carbohydrate and amino acid components. These gums have positive specific rotations and provide some interesting extensions to the ranges of analytical parameters established for the gum from A. seyal and the other Gummiferae species from which the well-known commercial gum talha is derived: thus A. fischeri gum has a high methoxyl content, A. kamerunensis gum is unusually acidic and A. spirocarpa gum has a fairly high protein content which contains one of the lowest hydroxyproline contents recorded for an Acacia exudate. These four Acacia gums are not permitted as food additives because (i) they arc not botanically related to Acacia senegal (L.) Willd. and (ii) they give positive reactions, which have been quantified, in the test for tannin contained in regulatory specifications for gum arabic (E414).