Preparation of soy protein-based meat analogs by freeze alignment technique: Experimental and modeling of ice crystal size control

Abstract

This study investigates the application of a freeze alignment technique to control ice crystal formation in soy protein-based meat analogs, a critical factor influencing the texture of the final product. Varying the freezing methods (air blast and plate freezing) and temperatures from −10 °C to −80 °C, resulted in various freezing rates and directions, which in turn affected the patterns of ice crystal formation. Ice crystal sizes (L*) were obtained experimentally, and the freezing front rate (R) and temperature gradient (G) were obtained from simulation results using the finite element method. The empirical equation, L* = 201.77 R^−0.03 G^−0.30, was validated against experimental data, with an overall prediction error of 14.74 %. The developed empirical equation serves as a general model for predicting ice crystal size across various freezing methods and temperatures. The results demonstrate that lower freezing temperatures and higher freezing rates produced smaller ice crystals, with average sizes ranging from 77 µm to 209 µm. The developed prediction model, supported by both experimental and simulation data, offers a valuable tool for optimizing the freezing process in the production of soy protein-based meat analogs. The results of this study emphasize the importance of controlling the freezing parameters, especially the temperature gradient, to achieve the desired microstructure in meat analogs produced via the freeze-alignment technique. This predictive equation is a key contribution to designing the textual characteristics of plant-based meat analogs.