High-pressure homogenization: A potential technique for transforming insoluble pea protein isolates into soluble aggregates

High-pressure homogenization (HPH) is a technique that impacts the aggregation of globular proteins. In this study, the effect of HPH (at a pressure of 30/50 MPa for three cycles) was investigated on the aggregation states and functional properties of insoluble commercial pea protein isolates (CPPI). Results showed that HPH significantly improved the solubility, foaming and emulsifying capacity of CPPI. Samples treated at 50 MPa demonstrated better foaming and emulsifying capacity than that at 30 MPa. Surface hydrophobicity, intrinsic fluorescence, SDS-PAGE and FTIR analysis revealed that insoluble precipitates/aggregates (most legumins included) of CPPI were broken down and converted into soluble aggregates. Low-pressure HPH (30 MPa) can break non-covalent bonds (hydrophobic interactions), whereas higher pressure (50 MPa) can further break covalent bonds (SS). The study sheds light on the mechanism of disruption of insoluble CPPI under HPH and proposes a method to enhance their techno-functional properties for application in food formulations.