Commercial sliced brown bread, obtained from the Oberfranken region of Germany was freeze.dried, ground in a ZrO2 planetary-mill and sieved through a 125 µm screen. The fraction retained was reground, seived again and the two fractions having a particle size less than 125 µm were combined.
The batches of material were homogenized in a PVC drum equipped with internal mixing vanes during a period of two weeks.
XRF was employed to demonstrate that thorough mixing had been achieved and the material was bottled by hand in units of 40 g. In order to minimze risl of de-mixing during the bottling procedure, the content of the drum were re-mixed after each series of 40 bottles had been completed.
keywords: Biological material, Plant material, Agricultural food products, Foodstuff, trace elements