Changes in mineral absorption inhibitors consequent to fermentation of <scp>E</scp>thiopian <i>injera</i>: implications for predicted iron bioavailability and bioaccessibility

Abstract

Summary Possible changes in mineral bioavailability during processing of different types of injera sampled in E thiopian households were assessed using different methods: phytic acid/mineral molar ratio, absorption prediction algorithm and in vitro availability measurements. Most foods analysed were rich in iron, but most of the iron likely resulted from soil contamination. The highest iron, zinc and calcium contents were found in teff–white sorghum ( T w S ) injera and flour. The lowest phytic acid/ F e and phytic acid/ Z n molar ratios were found in barley–wheat ( BW ) and wheat–red sorghum ( W r S ) injeras . Although ideal phytic acid/ F e molar ratios (&lt;0.4) were found in BW and W r S injeras , no significant difference between in vitro iron bioaccessibility and algorithm predicted absorption was observed. In injera , phytic acid degradation alone is unlikely to improve iron bioavailability, suggesting interactions with other absorption inhibitors. The use of phytic acid/ F e molar ratios to predict bioavailability may thus be less appropriate for iron‐contaminated foods.