It is obtained by hydrolyzing bovine cheese with trypsin, making CPP free and then purified by membrane separation after de-bittering by ion exchange resin. The origin of α-casein is α-CPP, and the origin of β-casein is β-CPP, and there are many kinds of products according to the different purification methods. The manufacturing process of the products of Meiji Fruit Manufacturing Co., Ltd. in Japan is as follows: Zheng Tiesong of Zhejiang University obtained casein from whey by isoelectric point precipitation method. According to the positive effect of the test with calcium holding capacity as an indicator, to find the best conditions: casein into a 15% solution, with 2 mol / L NaOH adjusted to Ph8.3 or so, according to the ratio of substrate and enzyme ratio of 100: 1 ratio to add trypsin for hydrolysis, hydrolysis process is always maintained in the solution of Ph value of 7.7 ~ 8.5 between the hydrolysis temperature of 40 ℃, after hydrolysis of 80min, add After 80 min of hydrolysis, 1 mol/L HCI was added to make the solution Ph value reach 4.8, centrifugation was used to remove the precipitate, and the supernatant was added with 10% CaCl2 solution to the final concentration of 100 mmol/L, and washed by ether and evaporated and dried, which was the finished product. The yield was 9.78%, and the calcium holding capacity (P:N) was 0.355.
