Study On Synthesis And Physi-chemical Property Of Ferrous Glycinate

Ferrous glycinate is a new type of iron fortificant, which have well characters and biological activities. Ferrous glycinate was synthesized using ferrous choloride or ferrous sulphate and glycine as raw materials in this thesis.The preparation of ferrous glycinate was firstly studied. By single factor experiments, the synthesis technology was confirmed. The optimal reaction condition is as follows, water bath temperature 50℃, pH 5.5, the molar ratio of glycine to ferrous 4 : 1, and the amount of complex antioxidants is 1 / 60 of the amount of glycine. The filtrate was treated with organic solvent and the ferrous glycinate was precipitated in organic solvent. Consequently, the chelate can be purified and analyzed by common chemical method. The volume ratio of organic solvent to filtrate of ferrous glycinate is 9 : 1. With this condition, ferrous glycinate was obtained which contained 9.11 % ferrous and the content of ferrous account for 80 % of total iron content.The Infrared spectrometry of ferrous glycinate showed that there were no characteristic absorption of free glycine and it exists with a chelating compound structure.Oxidation stability of ferrous glycine is significantly better than that of FeSO4 by the storing experiment. Hydrolyzing stability test showed that ferrous glycinate keep no hydrolyzation in water. On the contrary, FeSO4 solution hydrolyzed very fast and formed deposit of Fe(OH)2. whereafter oxidated to be Fe(OH)3, finally, turned to be Fe2O3 deposit.The applications of ferrous glycinate as an iron fortificant were investigated. Comparing the catalyzing effect to lipid oxidation. It was confirmed that ferrous glycinate had almost no catalyzing effect. Whereas FeSO4's catalyzing effect were expectable. The oxidation and decomposed mechanism of vitamin A in fortified flour was discussed. Storing in different temperature for a period of time, oxidation vitamin A in iron fortified flour were manifested to be decomposed with an exponential characteristic. Different temperature deeply affect the oxidation speed. The oxidation vitamin A in flour fortified with ferrous glycinate is less than that of FeSO4 control. Synthesis technology of ferrous glycinate was also discussed by making use of Ca(OH)2 to adjust reaction pH. Most CaSO4 was easily precipitated and filtrate was further treated with organic solvent. High purified ferrous glycinate was obtained with this method. Comparing the two different synthesis method of ferrous glycinate. in the present study, it was found that the product from organic solvent extraction has good water-solubility and oxidation stability, but moisture absorption is higher. On the contrary, ferrous glycinate from precipitation method has lower moisture absorption property, but its water-solubility is very poor.