Subcritical water extraction of hydrolyzed proteins from canola meal: Optimization of recovery and physicochemical properties

The objective of this study was to valorize hot-pressed, desolventized toasted canola meal by tailoring subcritical water extraction (SCW) conditions to enhance protein recovery while optimizing their physicochemical properties. A 3 × 3 face-centered central composite design using response surface methodology was applied to understand the interaction between extraction temperature (200–250°C), time (20–30 min), and feed concentration (5–20 %) at 4.03 MPa pressure and their effects on protein recovery, degree of hydrolysis (DH), interfacial tension (IFT), and total phenolic content (TPC). The extracts displayed a maximum protein recovery of 68.9 wt% with a maximum DH of 14.1 %. The extracted protein significantly reduced the IFT to a minimum of 4.0 mN/m. The extracts showed a high value of TPC (24.6 mg/g) and excellent antioxidative properties. Overall, it demonstrates the potential of SCW to transform low-value canola meals into high-value protein hydrolysates with enhanced surface activity and antioxidative properties for food and industrial applications.