*3.2. E*ff*ect of High Hydrostatic Pressure Coupled to Enzymatic Digestion on the Degree of Hydrolysis of Mealworm Proteins*

Figure 2 shows the evolution of DH for mealworm proteins digested by Alcalase® and pepsin under three different conditions: without pressure (control), HHP applied as a pretreatment before hydrolysis, and HHP applied simultaneously during in vitro digestion. The degree of hydrolysis during in vitro digestion of mealworm protein by Alcalase® increased rapidly from 0 to 10 min and linearly until the end of hydrolysis (120 min), no matter the condition (control, pretreatment, and simultaneous conditions) (Figure 2A). The evolution of DH was similar for the control and pretreatment conditions with respective final values of 32.29 ± 1.90%, 37.82 ± 3.43%, and 29.12 ± 0.95% (*p* > 0.05). However, the degree of hydrolysis under HHP (simultaneous condition) was higher than control (21.75 ± 1.27%) and pretreated (22.20 ± 1.89%) conditions up to 60 min (*p* < 0.05) (27.15 ± 2.02%), but remained similar from 60 to 120 min (*p* > 0.05).

The evolution of the DH during mealworm protein hydrolysis by pepsin was similar to that of Alcalase®, with values of 35.20 ± 1.87%, 29.01 ± 3.55%, and 32.31 ± 1.09% for the control, pretreated, and simultaneous conditions, respectively (*p* > 0.05) (Figure 2B). When compared to hydrolysis by Alcalase®, the DH increased steadily over time and was lower at the end of hydrolysis (120 min for Alcalase® and 240 min for pepsin).
