Accumulation of Selected Trace Elements in Hydroponically Grown Soybeans and Distribution of the Elements in Processed Soybean Fractions

Soybeans grown hydroponically labeled with 59 Fe or two levels of a 51 Cr‐ 65 Zn mixture were analyzed for the distribution of these radionuclides in mature edible and nonedible parts. The concentration of 59 Fe was significantly higher in the hulls than in other plant parts unlike for 51 Cr and 65 Zn. The seeds produced were then processed into a defatted soybean meal in order to investigate the effects of processing on the content of iron, zinc, and chromium. No detectable change in total Zn content and no significant change in 51 Cr content were evident during processing. However, an overall 9% gain of total Fe content was observed as a result of processing probably due to Fe contamination by processing equipment.