Discolouration by iron-phenolic interactions: colourful insights into the mechanisms and proposed solutions for food fortification

Summary

Iron deficiency anaemia is a global health problem that currently affects a quarter of the world’s population. Food fortified with iron can effectively reduce the global prevalence of iron deficiency. However, addition of iron to food can lead to undesirable discolouration due to interactions between iron and naturally present phenolics. Additionally, these interactions can reduce iron’s bioavailability. Our research created better insights into the chemistry of iron-phenolic interactions at the molecular level. We also explored strategies to limit iron-phenolic mediated discolouration of fortified foods. Firstly, we found that pH, type of iron salt, temperature, and the structural features of food phenolics significantly influence the discolouration mediated by iron-phenolic interactions. Secondly, we designed new iron salts that can potentially serve as iron fortificants for food due to their reduced reactivity with phenolics at food conditions and increased iron solubility at gastric pH, which implies improved iron bioavailability.