Study On Glycine-zinc Chelate Using As Food Additive

Zinc is the microelement necessary for human body, which exists in human body in the manner of protein and metal enzyme, performing various important biological functions. The zinc carrent in human body directly control various process of metaboly, if there is disorder in the process of metaboly in zinc ingestiom absortiom storage, using and excretion etc, it will lead to various pomology change even disease. Microelement is not like other things, which can not make in human body but only can acquire from outside body. Only a little zinc can be absorbed, food zinc can be absorbed by body are less than 10%.So, we must supply zinc reasonably. Zinc-glycine chelate is a new nutritional intensifying agent which has higher bioavailability than inorganic zinc.The zinc-glycine chelate was synthesized with glycine and zinc hydroxide as raw materials.The optimum technological conditions are that molar ratio of glycine to zinc hydroxide was 2:l,reac-tion temperature was 60C,reaction pH was 8.5,and reaction time was 2h.The yield was 52.6%.Composition and structure of the complex were characterrrized by elementary analysis,infrared spectrum,thermogravimetric and X-ray powder diffractionJts imposition is [Zn(NH2CH2COO)2] H2O. The results of indexization cf the X-ray powder diffraction data indicated that the crystal structure of the complex belongs to monoclinic system. The lattice parameters are: a=19.716(3)A, b=10.4590(ll)A,c=15.0965(18) A, alpha=90deg., beta=92.998 (3), garnma=90deg., V=3108.8 (7) A3, Z=16,DC=1.979g/cm3.The constants of zinc-glycine chelate were measured.The solubility of zinc-glycine chelate is 41.35mg/100gH2O.The melting point of zinc- glycine chelate is 282-284 C.The logarithms of stability constant in aqueous solution atpH=8.5 is 5.54. The oxidation resistance of zinc-glycine chelate was tested in soybeanoil.The result indicates that zinc-glycine chelate has higher ability of oxidation resistance than BHT in soybean oil.