Development of a simple method to simulate human digestion

Sammanfattning

Most trace elements that may pose a threat if accumulated in the human body, usually have limit values set for an acceptable intake, such as a daily intake. The purpose with this study was to observe the bioavailable fraction of 8 certain trace elements, by an optimization of method, thus this is a method development study. This study was conducted by using dried homogenized pooled milk samples, in which were exposed to different simulated environments. Factors such as pH, temperature and salt amount were changed to simulate the different tracts of the human digestion system such as the gastric tract and intestinal tract and to ensure analysis by ICP-MS. The extractable mass fractions of these trace elements from the gastric digestion as well as the intestinal digestion were compared to the extractable mass fraction from a total HNO3 digestion. Elements like lead and vanadium did exceed their limit values in drinking water. However, milk is not consumed in the same extent as drinking water and the extractable fraction is not that great, meaning that harmful effects should not be expected by consuming milk. Selenium was one trace element that was not found nor quantified in the sample. The intestinal digestion yielded higher extractable mass fraction than gastric digestion, and the total digestion method resulted in the highest extractable mass fractions and thus increasing the elements bioavailability. The amount of salt did not statistically significantly influence the bioavailability of the trace elements.