Effect of high pressure on the reaction between bovine myofibrils and cathepsin D

This study deals with the effect of high pressure [50-500 MPa] and time of treatment [20-900 s] on the reaction between myofibrils and cathepsin D from bovine post mortem meat, using Surface Response Methodology. We shown that every high pressure treatment enhanced activity of cathepsin D as evaluated on haemoglobin as a substrate or on control meat myofibrils. We also put in evidence that cathepsin D could carry out the hydrolysis of high pressure treated myofibrils. At last we studied the action of pressurised cathepsin D on pressurised myofibrils, and proved that the hydrolysis was increasing up to 170 MPa and then decreased; above 300 MPa the activity was lower than with control cathepsin D and control myofibrils. Thus above 300 MPa recognition of natural substrate is affected by high pressure induced modifications. These results may help to explain why high pressure treatment of post rigor meat is not able to increase tenderness.

Keywords:

• High Pressure
• Meat
• Enzymes
• Cathepsin D
• Myofibrils, Surface Response Methodology