Availability of Zinc and Comparison of In Vitro and In Vivo Zinc Uptake of Certain Oil Seed Meals ,

Abstract

ISOLATED soy protein has been widely used as a vegetable protein source for studying zinc metabolism in poultry. A relationship between the chick’s dietary zinc requirements and phytates has been suggested. The zinc content of isolated soy protein is very low, and its effect on the chick’s dietary requirement seems to be in increasing the amount of added zinc necessary to fulfill this requirement. Sesame meals contain phytic acid but differ from isolated soy protein in that they contain relatively large amounts of zinc. The availability of zinc from sesame meals varied (Turk and Lease, 1962). Some meals behaved in a manner similar to isolated soy protein in increasing the chick’s dietary requirement. Sesame meals fell into three classes: (1) those from which zinc is available to the chick, (2) those from which zinc is partly or not available and (3) those from which zinc is not only unavailable but …