Antioxidant activity, structural and physical properties of soy-based textured vegetable protein with added cannabis leaves as affected by extrusion process

The effects of cannabis leaf powder substituted for defatted soy flour (CP; 0%, 5%, 10% and 15%) and the moisture content of the mixture (MC; 25%, 35% and 45% on a wet basis) on physical properties and antioxidant activities of textured vegetable protein (TVP) prepared using a twin-screw extruder were studied. Increasing CP and MC decreased expansion, resulting in small air cells within the structure, which, in turn, led to an increased bulk density and decreased water absorption capacity, water holding capacity and water solubility index. After rehydration, TVP with the higher CP and MC levels tended to exhibit higher hardness and cohesiveness. An increase in CP significantly (P < 0.05) enhanced the total phenolic content and antioxidant activity of TVP as determined by DPPH, ABTS and FRAP assays. The preliminary consumer acceptance test indicated that TVP containing less than 10% CP and 25% MC tended to have higher overall liking score, with the texture resembling that of meat.