Abstract:The structure of amino acid chelated calcium was identified by infrared spectrum（IR），ultraviolet spectrum（UV），and scanning electron microscope（SEM），and the antioxidant，antibacterial，and digestive properties were analyzed.The UV and IR spectra showed that the chemical structure of the chelated products changed compared with that of non-chelated products.“White crystals”were clearly identified on the SEM images attached to the surface of the chelated products.These results confirmed the formation of amino acid chelated calcium.The chelated composite could effectively scavenge DPPH，hydroxyl，and superoxide anion radicals，and had good reduction ability and antioxidant activity.Further，the chelate had a significant antibacterial effect on Staphylococcus aureus，and to a lesser extent on Escherichia coli and Salmonella.An in vitro gastrointestinal digestion test showed that the calcium dissolution rate reached 90.38%after digestion for 2 hours.The calcium dissolution rate was maintained at 42.50%after the simulated intestinal digestion，indicating that the dissolution rate was high.