The Impact of Cooking of Beef on the Supply of Heme and Non-Heme Iron for Humans

Red meat contains a high proportion of heme iron (HI) which is absorbed at a far higher extent into the blood than the non-heme iron (NHI) found in plants. However, HI and NHI are expelled in the juice during cooking while a fraction of HI is converted into NHI, thus decreasing iron bioavailability. This paper relies on experiments and the use of modeling. The kinetics of the conversion of HI into NHI was measured and modeled in juice extracted from uncooked beef meat, and beef cubes were cooked to measure the variations of HI/NHI contents. In meat, HI/NHI ratio decreased from 2.0 when it was raw to less than 1.0 for the longest heat treatments and highest temperatures. The model was used to predict the effect of cooking conditions on the variations of the iron supplied by beef meat. The lowest contribution of meat to iron supply was found for under-pressure cooking at temperatures above 100°C.