Bioaccessibility and speciation study of iron in bovine tissue

Abstract

The content of total iron and total bioaccessible iron were determined in beef through visible spectrophotometry by the method of 1,10-Phenanthroline. The samples were cooked, dehydrated and prepared as jerked beef. They were submitted to a simulation of gastrointestinal digestion for the evaluation of bioaccessibility. Among the samples analyzed, the heart and the liver had the highest levels of total iron and total bioaccessible iron. After cooking the samples, there was an increased bioaccessibility of iron. The cooked liver and heart contributed respectively with 28% and 20% in terms of bioaccessibility The insertion of bioaccessibility in food composition tables is important, as it comes to nutritional information closer to reality. It was possible quantify the amount of Fe2+ in all samples, however, only Fe3+ was quantified in samples of cooked sun meat and in the samples of heart. The method was not sensitive enough to detect the heme iron and it was observed that an increase of ionic iron with cooking due to liberation of iron from the heme complex.