This work presents a mathematical model to simulate the extraction process of soluble protein from sabalo (Prochilodus platensis) during the surimi elaboration. The mathematical model consists of both partial differential and algebraic equations. Central finite difference method and the explicit scheme were applied to discretize the partial differential equation. The resulting model was implemented into the optimization environment General Algebraic Modeling System (GAMS). Experimental data obtained from laboratory scale using sabalo as raw material, was used to verify the output results of the proposed model. A good agreement between experimental and simulated extraction yields was obtained (R-2 = 0.9552). Once validated, the model was used to investigate the influence of several parameters such as, particle's diameter, volume fraction of the solvent, residence time and agitation velocity on the extraction efficiency. The results are presented and discussed through different case studies. (C) 2013 Elsevier Ltd. All rights reserved.