Comparative Study of Physicochemical <scp>and Structural</scp> Characteristics of Meat Analogues Produced From Soy and Wheat Proteins

Plant-based meat analogues are gaining attention due to rising environmental concerns and demand for sustainable dietary options. However, achieving desirable texture and structure remains a challenge. This study investigated how varying proportions of soy protein isolate (SPI) and wheat gluten (WG) affect the physicochemical, structural, and sensory properties of high-moisture extruded meat analogues. SPI and WG were blended in different ratios (0%, 15%, 25%, 40% WG) and processed using a twin-screw extruder under controlled conditions. Additional ingredients included 7% vegetable oil, 5% pumpkin powder, 3.7% wheat starch, and 0.3% salt to enhance structure, color, and palatability. Physicochemical, textural, microstructural (SEM), and sensory analyses were conducted. Formulations containing 40% WG exhibited superior fibrous texture, hardness, chewiness, and flexibility. SEM analysis showed increasing WG content enhanced fiber density and alignment; however, the ultrastructure (defined here as sub-micrometer fibrous morphology) remained consistent in type. Protein solubility results suggested that hydrogen bonds, disulfide bridges, and hydrophobic interactions stabilized the network. Combining SPI and WG under high-moisture extrusion enhances the fibrous characteristics of meat analogues. Optimizing the WG content leads to improved texture and structural integrity, offering a viable strategy for developing consumer-acceptable, sustainable meat substitutes.