Acacia gum Acacia gums, or gum arable, are Acacia-tree exudates that are highly branched galactan polymers with galactose or arabinose side chains terminated by rhamnose or glucuronic acid. It cannot be digested in the small intestine but behaves as a prebiotic by enhancing the growth of the probiotic bifidobacteria (Wyatt et al., 1986; Crociani et al., 1994). Michel and coworkers (199…