[Improved biological availability of zinc in coarse meal and crisp meal bread].

A study was undertaken to determine whether the reduction of the molar phytic acid/zinc ratio by enrichment of wholemeal and crispbread with zinc improves zinc availability to the same extent as does the reduction of phytic acid in whole meal cereal products. For three weeks, five diets (three samples of wholemeal bread and two samples of crispbread] were fed to growing rats. Significant increases in bone-zinc deposition and activity of serum alkaline phosphatase were induced by those bread samples in which the phytic acid/zinc ratio had been lowered either by enrichment with zinc or by reduction of phytic acid (enzymatic hydrolysis by adjusting the pH-value of the dough with lactic acid) when compared with untreated bread samples. Weight gain of the animals differed little between the groups. The results suggest that it is possible to improve zinc availability in wholemeal cereal products high in phytate by enrichment with zinc.