Optimization of Enzymatic Hydrolysis Conditions and Micromorphology of Bone Collagen Peptides from Donkey with Iron Chelating Ability

In order to make full use of donkey bone resources, a method was developed to hydrolyze donkey bone with protease to obtain donkey bone collagen peptide. The chelating ability of the enzymatic peptide with ferrous ions was investigated and its product was characterized. Using the ferrous ion chelation rate as the investigation index, the optimal enzyme species was screened, and the optimal enzymatic hydrolysis conditions of donkey bone were determined by single factor experiment and orthogonal experiment considering interaction. The results showed that the optimal pretreatment conditions for donkey bone were cooking at 121 ℃ for 30 min, papain was the optimal enzyme, and the optimized enzymatic hydrolysis process parameters were as follows: temperature of 50 ℃, pH of 7.0, enzyme-substrate ratio of 1 000 U/mL, time of 3 h, the chelation rate of donkey collagen peptide and ferrous ion was 38.40%, and the chelating product with sheet microstructure can be obtained. Papain enzymatic hydrolysis of donkey bone protein can prepare donkey bone collagen peptide with the ability to chelate ferrous ions, promoting iron absorption, and guiding the development of donkey bone collagen peptide related products.