Absorption of calcium, magnesium, phosphorus, iron and zinc in growing rats fed diets containing either phytate-free soybean protein or soy-bean protein isolate or casein.

There is a lot of new research underway to evaluate the nutritional properties of genetically enhanced soybeans. Research conducted in Japan compared the effects of phy-tate-free soybean protein on the absorption and retention of minerals in growing mate rats. The rats were fed diets con-taining phytate-free soybeans, soybean protein isolate or casein at a 20 percent level for five weeks. Levels of calci-um, magnesium, phosphorus, iron and zinc in the experi-mental diets were adjusted with mineral salts. Results indi-cated that the mineral absorption and retention ratios in rats fed the phytate-free soybean protein diets were significantly higher than those in rats fed the isolated soy protein or the casein diets. The significance of these results is that soy-bean breeders and biotechnicians are now able to develop soybean varieties specifically designed to improve mineral bioavailability in diets formulated for livestock and poultry.

Kamao, M. and co-workers. 2000. Absorption of calcium, magnesium, phosphorus, iron and zinc in growing rats fed diets containing either phytate-free soybean protein or soy-bean protein isolate or casein. J. Nutritional Science and Vitaminology 46(1):34-4 1.