Edible Cactus Powder-Enriched Cassava and Rice Flours as Fiber-Enriched Plant-Based Ingredients: Physicochemical, Rheological, Freeze–Thaw Properties and Starch Digestibility

Understanding how plant-based ingredients influence the functional properties of starch-based flours is important for their potential applications in gluten-free food development. This study investigated the incorporation of edible cactus powder (CP) into cassava flour (CF) and rice flour (RF) at 5%, 10%, and 15% and evaluated its effects on their physicochemical, structural, pasting, rheological, freeze–thaw, and in vitro starch digestibility properties. CP incorporation increased crude fiber content from 0.32 to 3.41 g/100 g in CF and from 0.73 to 2.55 g/100 g in RF at 15% CP, while increasing the measured levels of bioactive compounds and antioxidant activity. SEM, FTIR, and XRD analyses indicated changes in the morphological, spectral, and diffraction characteristics of the flour blends. CP generally reduced the viscoelastic moduli (G′ and G″), apparent viscosity, and most pasting viscosity parameters, while reducing freeze–thaw syneresis under the experimental conditions. Furthermore, CP-fortified flour blends generally exhibited lower rapidly digestible starch (RDS) and higher slowly digestible starch (SDS) fractions, providing preliminary insights into their in vitro starch digestibility characteristics. Overall, the findings provide preliminary insights into the physicochemical and functional characteristics of CP-fortified flour blends and a basis for further investigation of their potential applications in gluten-free food formulations.