Legume protein composition influences texturization during high temperature protein-starch complexation
Lavaraj Devkota, Gaurav Kumar, Pangzhen Zhang, Vikram Singh Raghuwanshi, Sushil Dhital
Abstract
Despite the frequent use of starches in formulating products like meat analogues, there is a notable lack of research and literature addressing the interaction between proteins and starches at high temperatures. This gap in scientific understanding is particularly significant given the widespread application of starches in protein-based food products that undergo high-temperature processing. This study investigates the gelation behaviour of plant proteins (lupin) with varied legumin to vicilin like protein ratios and their interactions with maize starches of different amylose contents. Using a High-Temperature Rapid Visco Analyzer (HTRVA), we simulated industrial processing conditions to assess the structural changes in these protein-starch systems under high-temperature conditions. The pasting properties were evaluated at 95 °C, 110 and 120 °C, while gel strength was assessed using a texture analyser. Size exclusion chromatography (SEC), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and small-angle X-ray scattering (SAXS) were employed to study molecular size, thermal properties, crystallinity, and nanoscale structures, respectively. Our findings reveal that not only the quantity, but the ratio of vicilin-like to legumin-like protein significantly impacts the gelation process, with the presence of maize starch further influencing the textural properties of the gels. Specifically, high amylopectin starches contributed to higher peak viscosity, gel strength and stability. Higher legumin-like protein content was associated with improved gel strength and stability, likely due to enhanced protein-protein interactions and network formation. These findings contribute to a better understanding of how protein-starch interactions can be optimized to create plant-based gels with desirable textural and functional properties. • Vicilin-to-legumin like protein ratio in lupin protein impacts gel texture and stability. • Waxy maize starch enhances peak viscosity, aiding albus protein gel strength. • High temperatures cause early vicilin denaturation; new crystalline structures form. • Legumin-like rich Angustifolius suits firm textures: vicilin-like rich Albus ideal for soft, quick-gelling applications.