Optimization of preparation of calcium-lysine chelate from bay scallop shell by response surface method

In order to increase utilization of waste bay scallop shell, the preparation technology of calcium-lysine chelate from scallop shell was studied.Calcium chelating calcium was prepared from scallop shell and L-lysine under certain conditions.The effects of reaction temperature, time, L-lysine and Ca²⁺ molar ratio and p H value on chelate yield were investigated to determine reasonable preparation process.Response surface test was carried out on the basis of single factor experiment, and the chelating process was determined as follows-reaction temperature was 63.4 ℃, reaction time was 34.0 min, the molar ratio of L-lysine and Ca²⁺ was 2.1∶ 1, pH value was 8.4.Under the optimum conditions, the chelate yield of product was 82.16%, and the calcium content in chelate was about 9.58%.Fourier transform infrared spectroscopy showed that calcium ions and L-lysine chelate reaction occured, formed Ca-N bond and Ca-O bond, and produced calcium-lysine chelate.