Absorption of zinc from Iupin (Lupinus angustifolius)-based foods

Abstract

The absorption of Zn from a lupin ( Lupinus angustifolius ) milk fortified with Ca, a bread containing lupin flour (230 g/kg), a sauce containing lupin flour and a sauce containing a lupin-protein isolate was determined in humans by measuring the whole-body retention of radioisotope from meals labelled with 0·02 MBq 65 Zn, allowing for endogenous excretion of Zn, after 14 d. The absorption of Zn from the Ca-enriched milk (16·2%) and the bread made with lupin flour (27·0%) was similar to literature figures for comparable soya-bean products. The absorption from composite meals made with lupin flour (28·2%) and protein isolate (32·7%) was significantly higher than that reported for comparable soya-bean products. In a second experiment the absorption of Zn from a lupin-milk base and a soya-bean-milk base was compared with that from Ca-supplemented bases. The absorption of Zn from the lupin-milk base (26·3%) was significantly higher than from the soya-bean-milk base (17·6%), and neither was significantly altered by the addition of Ca. Overall the absorption of Zn from lupin-protein foods was found to be higher than from comparable soya-bean products. Lupin milk could be an attractive alternative to soya-bean milk for infant formulas.