Study on the Modification and Physicochemical Properties of Hemp Protein Isolate by Ultra-High Pressure Assisted Enzymatic Hydrolysis

Hemp protein isolate (HPI) was used as raw material to modify HPI through ultra-high pressure assisted enzymatic hydrolysis reaction. The solubility and degree of hydrolysis were used as criteria to screen the optimal conditions for the enzymatic hydrolysis modification. The influence of ultra-high pressure assisted enzymatic hydrolysis on solubility, foaming, emulsification, water retention and oil retention of enzymatic hydrolysis products was explored. The results showed that the optimum conditions for HPI enzymatic reaction were as follows: Adding amount of enzyme (complex protease) 5000 U/g, pH8.0, temperature 55 ℃ and time 50 min. Taking HPI as the control, when the pressure was 200 MPa, the solubility, foaming property, emulsification property and oil holding capacity of enzymatic hydrolysis products were the highest, when the pressure was 100 MPa, the foaming stability was the best, the emulsification stability after enzymatic hydrolysis had different degrees of decline, when the pressure was 0.1 MPa, the water holding capacity reached the maximum. In conclusion, the ultrahigh pressure technology can effectively promote the enzymatic hydrolysis modification reaction of HPI, and the physical and chemical properties of the enzymatic hydrolysis products were the best when the pressure is 200 MPa.