Combined effects of high-pressure and enzymatic treatments on the hydrolysis of chickpea protein isolates and antioxidant activity of the hydrolysates

A chickpea protein isolate (CPI) was pretreated before hydrolysis under a pressure that varied between 100 and 600 MPa. The hydrolysis rate increased significantly with pressure above 300 MPa. At 40 min, the DH of the control was 15.3%, while the DH of the CPI treated at 300 MPa was 18.5%, which reached 23.74% post treatment at 400 MPa. The pretreatment of CPI above 300 MPa enhanced the superoxide anion capturing rate of enzymatic hydrolysis. Pretreatment at 400 MPa significantly reduced the hydrolysis time with the release of antioxidant peptides. While hydrolysis by Alcalase during treatment at high pressure (100-300 MPa) significantly increased the degree of hydrolysis (DH), its maximum value peaked after hydrolysis at 200 MPa for 30 min. In addition, hydrolysates obtained at high pressure (100-300 MPa) had a higher superoxide anion capturing rate. High-pressure treatment at 200 MPa for 20 min resulted in products with high antioxidative activity. The molecular-weight (MW) determination of the enzymatic hydrolysates indicated that hydrolysis at high pressure could significantly increase the amount of low-molecular-weight peptides. (C) 2012 Elsevier Ltd. All rights reserved.