Influence of Dry and Steam Thermal Pretreatments on the Structural Properties and Flowability of Faba Bean Flours

Faba beans are emerging as a promising alternative protein source for bakeries, snacks, cereals and ready-to-eat foods. The quality and consistency of such products depend strongly on the processing behaviour of their flours, including handling, storage, mixing and extrusion performance, all of which are governed by flour flow and structural characteristics. However, there is currently a lack of information on the structural and flow properties of thermally treated faba bean flours. This study aims to understand the influence of dry and steam-heating temperature (70°C–100°C for 15–45 min) on the physical, structural and flowability properties of faba bean flours. Moisture content consistently decreased with high drying temperatures and longer duration for dry heating and vice versa for steam treatment. Dry-treated samples exhibited reduced particle size (D₅₀ = 14.5–18.9 μm), contributing to enhanced grindability but also increased cohesiveness. Fourier-transform infrared (FTIR) analysis revealed conformational changes in protein and starch domains, confirming that heating mode and moisture jointly influence molecular structure and powder behaviour. Flow indices (ffc) classified dry-heated flours as cohesive to very cohesive (ffc = 1.61–2.91), whereas steam-treated samples, particularly at 70°C for 15 min, were easy flowing (ffc = 4.24). Principal component analysis explained 70.78% of the variance, distinguishing treatments based on moisture and flow attributes. These findings demonstrate that controlled thermal pretreatments can be used to tailor faba bean flour handling properties, facilitating their use in food manufacturing processes such as flour conveying, blending and hydration-based applications where powder flow and stability are critical.