Influence of extrusion process parameters on specific mechanical energy and physical properties of high-moisture meat analog

To investigate the effect of process parameters during high-moisture extrusion on system parameter (specific mechanical energy, SME) and product physical properties, blend of soy protein isolate, wheat gluten, and corn starch (50:40:10 w/w) was extruded using co-rotating twin screw extruder equipped with cooling die at 55 and 65% feed moisture, 150 and 170 degrees C barrel temperature, 150 and 200 rpm screw speed. The hardness and chewiness of products increased as all the extrusion process parameters became low. Among the tested range of process parameters in this study, a combination of high moisture (65%), high barrel temperature (170 degrees C), and low screw speed (150 rpm) generated the low SME input (less energy consumption) with high texturization degree of meat analogs. Layer and fibrous structure formation of the samples were influenced by variations in process parameters, primarily feed moisture and barrel temperature.