The aim of this study was to develop a mathematical protocol (MP) to graphically analyze the irreversible changes induced by high pressure treatment in fish muscle protein. The MP was validated by thermal analysis data (DSC) from pressurized samples of Seriolella violacea muscle tissue between 200 and 500 MPa for 2s to 10 min. The MP included methodologies to obtain the thermodynamic parameters of protein denaturation and building 3-D plots from representative thermograms. Results obtained from the application of the MP showed that the pressurization of muscle tissue provoked that the total denaturation enthalpies values diminished, these changes were more evident for treatments > 450 MPa. The irreversible denaturation of actin in the pressurized samples was observed for any treatment condition > 300 MPa and greater than 3 min. The proposed MP is a powerful tool to improve data analysis from DSC when muscle tissue samples are subjected to pressurization. (c) 2017 Elsevier Ltd. All rights reserved.