Non-haem iron availability from pork meat: Impact of heat treatments and meat protein dose

Pork meat heated at 60, 80, 100, and 120°C (1h), raw pork meat, BSA, casein and haemoglobin were examined for their effects on in vitro iron availability measured as Fe(2+)-dialysability, and on iron-reducing capacity following in vitro protein digestion (IVPD-dialysis). The pepsin-digested samples of meat heated at 80, 100, and 120°C resulted in increased in vitro iron availability. Generally, the capacity to reduce Fe(3+) to Fe(2+) was higher in the pepsin digests, whereas Fe(2+) decreased significantly after pepsin+pancreatin digestion and only part of the Fe(2+) was dialysable. Regardless of protein concentration, casein had no effect on in vitro iron availability, while pork meat protein treated at 120°C showed dose dependency reaching a plateau at 50mg protein/ml. In conclusion, the major effects on iron availability in vitro was shown in pepsin digests under conditions mimicking those in the duodenal lumen and heat-treatment of meat at 120°C showed the most pronounced effects.