Phytate:zinc and phytate X calcium:zinc molar ratios in selected diets of Ethiopians

Abstract

The phytate:zinc and phytate x calcium:zinc molar ratios of selected Ethiopian diets were determined. The effect of these molar ratios on zinc solubility (index of bioavailability) from the selected diets (porridge, gruel, sour dough bread, yeasted bread, kitta, and injera) was estimated using the in vitro method. The mean phytate:zinc and phytate x calcium:zinc molar ratios of the unfermented diets were grater than 10 and 0.5 M/kg, respectively, while injera and sourdough bread exhibited ratios less than the suggested critical values of 10 and 0.5 M/kg, respectively. Fermented gruel had phytate:zinc and phytate x calcium:zinc molar ratios slightly greater than the critical values. Diets with low phytate:zinc and phytate x calcium:zinc molar ratios exhibited relatively higher bioavailability of zinc. Thus, the molar ratio phytate:zinc and phytate x calcium:zinc predict the adequacy of zinc nutriture in a given diet.