Optimizing Nutritional and Functional Properties of Gluten‐Free Grass Pea and Quinoa Instant Flours: Dual Modification by Sprouting and Extrusion

The growing demand for gluten-free products (GFP) among individuals with celiac disease and those adhering to gluten-free diets has prompted research into alternative flour sources offering enhanced nutritional profiles. This study investigated how sprouting and extrusion affect the quality attributes of GFP-based instant flour. The effects of feed moisture content (14%, 17%, and 20%) and whole sprouted grass pea (SGP): sprouted quinoa (SQ) blends (25:75, 50:50, and 75:25 w/w) on the macro and microstructure, functional properties, and nutritional properties of extrudates were analyzed using a central composite design. Results revealed that optimal conditions were 18.94% feed moisture content and a 75:25 SQ:SGP ratio. Under these conditions, significant increases were observed in porosity, water absorption index, and antioxidant properties, along with reduced hardness (<i>p</i> ≤ 0.05). The extruded flour exhibited improved particle size, protein, total dietary fiber, soluble fiber, antioxidant activity, and functional properties compared to the untreated flour. Notable improvements in flowability (Carr index and Hausner ratio), dispersibility, <i>a</i>* and <i>b</i>* attributes were observed in the extruded flour compared to the untreated flour.