Investigation into heat-induced lentil globulin–porcine albumin protein interactions

Hybrid food systems can be mobilized to enhance or develop specific textural attributes as part of food industry efforts to transition toward more sustainable and innovative solutions. In an unprecedented way, the study aimed characterizing and understanding the impact of porcine liver albumin (PA) and lentil globulins ( i.e. , lentil protein isolate; LPI) thermal denaturation on their mixture interactions using a panel of experimental characterization methods such as differential scanning calorimetry (DSC), rheology, scanning electron microscopy (SEM), and atomic force microscopy–force spectroscopy (AFM-FS). DSC was used to determine the denaturation temperatures of LPI and PA alone, which were 85 °C and 80 °C, respectively. We then evaluated the rheological properties and microstructure of thermal gels from 5% protein solutions at different LPI:PA protein ratios (0:100, 30:70, 50:50, 70:30 and 100:0). The mixed-protein combinations showed synergistic interactions. Up to concentrations of 50% LPI in the gels, the mixed gels showed lower enthalpy change, higher elastic modulus (G'), higher critical strain, and much lower frequency dependency that together demonstrated a stable elastic structure with superior resistance to deformation. The mixed gels also had a more compact and structured protein network. Using AFM-FS showed that protein–protein interactions were enhanced by thermal denaturation, and the forces measured were consistent with hydrophobic interactions and hydrogen bonds. This work opens up prospects for new ways of adding value to albumin-rich animal by-products. • Denaturation temperature was 85°C for lentil globulin and 80°C for porcine albumin • Heat treatment promoted lentil globulin–porcine albumin interactions • Porcine albumin increased the strength and resistance of thermal gels • Synergistic interactions occurred in the mixed gels • Mixed gels showed a more ramified and ordered network compared to pure gel