Development of texturized pea (Pisum sativum L.) protein and shiitake (Lentinus edodes P.) mushroom protein-based patties: extrusion optimization, physicochemical properties, and sensory acceptability

The development of texturized legume proteins (TLP), particularly from pea protein, is often limited by the globular structure of plant proteins, which restricts the formation of fibrous textures. This study demonstrated that optimised extrusion conditions enhanced the fibrous structure of texturized pea-shiitake mushroom (TPSM) protein using a single-screw extrusion process. A Box-Behnken design under response surface methodology was applied to optimise feed mixture composition (pea protein isolate (PPI) and shiitake mushroom (SM)), barrel temperature, and screw speed. The optimal conditions identified were 80.91% PPI:19.09% SM, 150 ℃ barrel temperature, and 151.41 rpm screw speed. These conditions significantly affected the integrity index and water absorption capacity, with barrel temperature being the most influential factor. Chemical analysis showed a protein content of 73.49 ± 0.3% and a favourable amino acid profile, while protein solubility decreased significantly after extrusion. TPSM exhibited higher water absorption capacity, lower oil absorption capacity, no gelling formation (2–20% w/v), and no significant effects on foaming and emulsifying properties. When TPSM was incorporated into beef patties (20–80%) and compared to a positive control (100% beef), notable improvements were observed in the cooking properties and nutritional profile. Sensory evaluation indicated moderate acceptance (hedonic score 6/9), particularly at 20% TPSM substitution, especially for flavour and texture attributes. These findings highlight the potential of TPSM as a functional ingredient in alternative protein applications.