Effects of phytase, cellulase and dehulling treatments on zinc in vitro solubility in faba bean (Vicia faba L.) flour and seed fractions

Abstract

SummarySimulations of gastro‐intestinal digestion was used to try to identify the nature of the complexes between antinutritional factors and zinc in faba bean fractions. In the hull fraction, the action of phytases and the simultaneous action of cellulase and phytase allowed about 7% and 35% additional zinc to be solubilised, respectively. Single enzymatic degradation of phytates from dehulled faba bean allowed solubilisation from 65% to 93% of zinc depending upon the treatment. The zinc of faba bean flour was mainly linked to phytates and the greater the degree of phytate degradation before in vitro digestion, the greater the quantity of zinc released. In dehulled faba bean zinc was almost exclusively chelated by phytates. In the hull of faba bean, the majority of zinc was chelated in complexes between phytates and fibres.