Modification of Faba Bean Protein Gels Using Thermal Treatment and Calcium Sulphate

Abstract

Faba bean protein concentrate (FPC) offers promising applications in the food industry, particularly in the formulation of plant-based meat and dairy alternatives, because of its versatile functional characteristics. This study examined the impact of thermal treatment on functional properties of FPC and the textural properties of its gels when using CaSO₄ as a coagulant. The thermal treatment involved a 30-min saturated steam treatment at 100°C in a commercial combination oven, followed by 10 min of fluidised-bed drying at 140°C, applied to dehulled faba bean seed material prior to dry fractionation. The functional properties of untreated and thermally treated FPCs, including protein solubility and water-holding capacity, were assessed. Subsequently, heat-induced gels were prepared with the faba bean protein material concentrations ranging from 12% to 16% w/w and CaSO₄ concentrations from 0.0% to 0.5% w/w and analysed for water-holding capacity, pH, textural and rheological properties. Thermal treatment resulted in a 32% reduction in protein solubility of the FPCs, while enhancing water-holding capacity by 2.2-fold. Gels formed with thermally treated FPC exhibited significantly higher stiffness and hardness, as well as altered rheological properties, including higher storage, loss modulus, yield stress and flow stress. The combination of thermal treatment and CaSO₄ significantly improved the textural and rheological properties of the gels, suggesting a synergistic effect. These findings demonstrate the potential of thermal treatment and salt coagulants to modulate the gelation properties of pulse protein concentrates, offering sustainable strategies for developing plant-based edible gels with enhanced functionality.