| Abstract: | An in vitro incubation at pH 2 of citric and malic acids with each of five iron sources (hydrogen (HRI) and electrolytically reduced elemental iron (ERI), ferric chloride (FeCl3), ferrous sulfate (FeSO4) and ferric orthophosphate (FOP)] at a 10:1 molar ratio (acid:iron) was evaluated for its effect on iron solubiliza-tion in a wheat flake cereal subjected to a sequential gastrointestinal pH treatment from endogenous pH (E) to 2 to 6. Citric acid maintained significantly more complexed and ionic iron (Fe+3) in solution than malic acid, with and without incubation, through the final stage of the sequential pH treatment with each of the five iron sources. However, the malate treated samples were affected less than the citrate by acidification from pH E to 2, with less of the soluble complexed iron being insolubilized and significantly more ionic iron (Fe+2) being produced. Incubation significantly enhanced the iron solubilizing capacity of citrate at all stages of the sequential pH treatment with HRI and at pH E with ERI, FeCl3 and FeSO4, As well, incubation increased the iron solubilization properties of malate at all stages with FeSO4 and at E and 2 with HRI and ERI. These results indicate that acid incubation to form an organic acid-iron chelate, particularly with elemental iron, has the potential to improve cereal iron fortificant bioavail-ability. |
