The impact of high-pressure homogenization on thermal gelation of Arthrospira platensis (Spirulina) protein concentrate

Abstract Gelation is an important techno-functionality for novel protein sources. Yet, only one study has focused on the gelling potential of concentrates from the microalgae Spirulina, despite its potential as a sustainable protein source. That study reported relatively low stiffness, hindering the application. The current study focuses on Spirulina protein concentrate (SPC) gel characterization and the utilization of high-pressure homogenization (HPH) before thermal gelation to improve gel properties. We reveal that the gelation is possible at pH 6.5, yet not at more acidic pH due to insufficient protein solubility. Phycobiliproteins - the main proteins in SPC, aren't responsible for gel network formation. The application of HPH at 50 MPa, as a pretreatment increased protein solubility by 91%. The surface hydrophobicity increased by at least 212% while decreasing particle size. Those HPH effects on SPC dispersion were correlated with an increase in gel stiffness and a decrease in the gelation point.