Pulsed Electric Field Processing of Liquid Milk Protein Concentrate 85 (MPC85) to Enhance Protein Functionality

Milk protein concentrate 85 (MPC85) is a high-protein dairy ingredient widely used in a variety of foods and prone to performance challenges with certain applications. To address the performance limitations, this study explored pulsed electric field (PEF) processing, a nonthermal method known to alter protein behavior and functional properties. The impact of PEF processing on liquid MPC85 was assessed for solubility, foaming capacity and stability, emulsion stability, gel strength, and water-holding capacity. Key parameters examined were temperature (25°C–50°C), electric field strength (4–20 kV/cm), and frequency (30–300 Hz). Predicted individual optimized conditions were as follows: For foaming capacity, the minimum (92.35 mL/g; 29.4% lower than the control) was predicted at 25°C, 12.45 kV/cm, and 32.21 Hz and maximum (153.86 mL/g; 17% higher than the control) was predicted at 49.35°C, 19.58 kV/cm, and 119.06 Hz. Maximum emulsion stability (55.12 min; 70.2% higher than the control) was at 50°C, 5.9 kV/cm, and 30 Hz, and the maximum gel strength (4751.33 N; 131% greater than the control) was at 50°C, 4 kV/cm, and 300 Hz. All models showed a good fit to the experimental data. Results demonstrated that foaming stability, water-holding capacity, and solubility did not show significant improvement under the tested conditions. In conclusion, PEF could be potentially used as a tool to modify the structure of the MPC85 to further promote the application of high-protein ingredients in the dairy industry.