• In vitro iron accessibility;
  • iron availability;
  • cereals;
  • polyphenols;
  • tyrosinase;
  • oxidation

ABSTRACT: Tannic acid and green tea extract were added to a model food system of wheat bread, before and after incubation with polyphenol oxidase (mushroom tyrosinase), and the effect on In vitro iron accessibility was studied. Tannic acid and green tea extract had a marked inhibitory effect on the In vitro accessibility of iron when added to the model food system. Incubation of the polyphenols with tyrosinase before addition to the model food system significantly increased the accessibility of iron. The results from the study therefore suggest that oxidation of polyphenols may be a promising way to increase the bioavailability of iron in polyphenol containing foods.