Enhancing the Foaming Properties of Pea Protein through Enzymatic treatment and High-Pressure Homogenization

Commercial pea protein isolate (PPI) is widely recognized as a sustainable alternative to animal proteins. However, like most plant proteins, it has limited techno-functional properties due to its denaturation and aggregation during industrial processing. This study investigates the combined use of high-pressure homogenization (HPH) and enzymatic hydrolysis to improve the foaming properties of commercial PPI. A 5% (w/w) PPI solution was treated at 1000 bar using a high-pressure homogenizer (PandaPLUS, GEA, Germany) at room temperature and adjusted to pH 5. This condition (1000 bar pH 5) was selected due to its high foam stability, despite its limited foaming capacity (overrun 140%). To enhance overrun, samples were hydrolyzed with HT200 protease (40 °C, enzyme/substrate ratio 1:10). Particle size (Mastersizer 3000, Malvern) and soluble fraction were evaluated, along with foam properties after whipping for 3 minutes at 200 rpm (Griffin & George stirrer, room temperature). Interfacial properties of the hydrolysates were analyzed using a Tracker tensiometer (Teclis, Germany). Hydrolysis time was inversely correlated with interfacial tension, improving surface activity. Particle size showed no significant changes after enzymatic treatment. Overrun increased with hydrolysis time, reaching 350%, but foam stability decreased, due to the elasticity reduction of the interfacial film. To obtain a sample with both high foaming capacity and stability, mixtures of the 15-minute hydrolysate with the original sample were prepared at 50:50 and 25:75 (hydrolyzed/non-hydrolyzed) ratios. The mixtures achieved an overrun of 250%, maintaining a high foam stability. These results highlight the potential of combining green processing strategies (HPH and enzymatic hydrolysis) to enhance the foaming performance of commercial PPI, supporting its application in plant-based products.