Binding of Ca by three starchy legumes in the presence of Ca alone or with Fe, Zn, Mg and Cu

The Ca-binding capacity of butter beans, broad beans and lentils in the raw, cooked and fibre-rich fraction (FRF) forms, with Ca addition alone and with Fe, Zn, Mg and Cu (at amounts based on the recommended daily allowance), was investigated in conditions simulating the small intestine. Overall, more Ca was bound when Ca was added with Fe, Zn, Mg and Cu than when Ca was added alone. Cooking significantly increased the Ca-binding capacity of the raw legumes when Ca was added alone. The FRFs gave the highest Ca-binding capacity in comparison to the raw and cooked legumes. The results suggest that the mineral-binding capacity of dietary fibre may influence mineral absorption.