Supercritical fluid extrusion of pea flour and pea protein concentrate: Effects on functional and structural attributes

This research investigated the effectiveness of supercritical fluid extrusion (SCFX) to modify the functional and structural characteristics of pea protein concentrate (PPC) and pea flour (PF). The results indicate that the SCFX process favorably modified the hydration properties of PPC and PF needed for developments in the structural and textural qualities of the meat analogs and other similar products. The water-holding capacity of extruded PPC and PF improved significantly. The SCFX-extruded samples showed greater emulsifying activity and stability index compared to the unextruded samples. The reduced solubility of the extruded samples indicates changes in the native protein structure and further denaturation due to the SCFX process. Denaturation is a prerequisite for protein texturization to produce meat analogs. Enhanced exposure of sulfhydryl (SH) groups indicates the favorable modification of the protein structure after extrusion. Free SH groups participate in covalent intramolecular disulfide linkages during the solidification process, enhancing the fibrous degree and formation of anisotropic structures. Additionally, the increase in surface hydrophobicity observed in the extruded samples demonstrates the ability of the SCFX process to enhance hydrophobic interactions among protein molecules, resulting in a stronger network formation. Overall, these findings showed the potential of SCFX processing as an innovative technique to effectively modify the structural and functional properties of PPC and PF, thereby enhancing their potential utility in creating novel food products from pea proteins.