Protein Functionality is Critical for the Texturization Process during High Moisture Extrusion Cooking

This study aimed to understand the importance of protein functionality in the extrusion texturization process for the development of high moisture meat analogs (HMMAs). Wheat and pea proteins were extruded, and part of the extrudates was freeze-dried and extruded again. Unextruded and extruded materials were analyzed for their physicochemical properties, including sulfur-containing groups and solubility in different extractants. Additionally, polymeric protein fractionation and texture analysis were conducted. Extrudate quality decreased with the second extrusion step. The obtained data suggest splitting of existing disulfide bonds and reformation to a large disulfide-linked network. Since single and dual extruded materials differed even though they exhibited the same amount of disulfide bonds, it is suggested that protein characteristics, including primary and secondary structures as well as rheological and melting properties, are of significance. However, further research is needed to fully understand the factors contributing to texturization.