Zinc Chemical Form in Some Traditional Soy Foods

The distribution and chemical form of zinc of several foods prepared from soybean were analyzed. There was a marked variation among soy foods in total zinc, water-soluble zinc, and zinc solubilized on enzymatic digestion. Chromatographic analysis indicated several zinc components were solubilized ion digestion. A significant negative correlation was found for % zinc solubilized after the digestion of soy foods to the original contents of three components, i.e., protein, phosphorus and calcium. Variations among soy foods in chemical form of zinc after digestion should be taken into account on evaluating bioavailability of zinc from soy foods.