| Taking hemp seed meal as raw material, hemp protein isolate hydrolysate rich in branched amino acids was prepared by two-step hydrolysis of pepsin and flavourzyme and dearomatication by activated carbon. The quality of hemp protein isolate hydrolysate was evaluated by antioxidant properties and solubility. The results showed that the optimal hydrolysis conditions of pepsin were obtained as follows: solid-liquid ratio 1∶ 5, amount of enzyme 0.9%, pH 2.5, enzymolysis temperature 37 ℃ and enzymolysis time 5 h. The optimal hydrolysis conditions of flavourzyme were obtained as follows: enzymolysis temperature 50 ℃, amount of enzyme 0.8%, pH 7 and enzymolysis time 4 h. Under these conditions, the degree of hydrolysis and A280 were (33.01±0.43)% and 0.321±0.002, respectively. Compared with hemp protein isolate(HPI), the solubility of hemp protein isolate hydrolysate (E-HPI) was significantly improved and it was(83.67±2.45)% at pH 7. The content of branched amino acid of E-HPI was 2337%, significantly higher than that of HPI. The antioxidant results showed that the scavenging rates of E-HPI on ·OH and DPPH· were 1.15 times and 1.58 times higher than that of HPI. |
