Process Optimization and Validation of Functional Pasta Reformulated with Lupin and Flaxseed Flours: Impacts on Technological Quality, Bioactive Potential, and Sensory Attributes.

Traditional wheat-based pasta is widely consumed; however, its reformulation with functional plant-based ingredients remains challenging because technological quality, bioactive properties, and consumer acceptance must be balanced. This study aimed to optimize and validate a functional pasta formulation by partially replacing wheat flour (WF) with lupin flour (LF) and flaxseed flour (FF). A 2² central composite rotatable design was applied, using LF (2-12%) and FF (5-15%) as independent variables. Instrumental color, cooking properties, texture, total soluble phenolic compounds (TSPC), antioxidant capacity (ORAC), and sensory acceptance were evaluated. Flour substitution significantly affected pasta quality, particularly color, cooking behavior, and texture. Increasing FF reduced lightness and increased redness, whereas higher LF contributed to yellowness. Although cooking and texture properties were modified, several formulations maintained acceptable technological performance, with low cooking loss and suitable texture-related attributes. Enriched pasta showed significantly higher TSPC and ORAC values than the control, indicating enhanced bioactive potential. Sensory evaluation revealed moderate to high acceptance, although excessive substitution negatively affected color and texture perception. Sensory acceptance was mainly associated with texture, stickiness, and cooking time. Numerical optimization identified an optimal formulation with 12.0% LF and 12.13% FF, achieving an overall desirability of 77.3%. Validation assays showed good agreement between predicted and experimental values, confirming model adequacy. Overall, lupin and flaxseed flours are promising ingredients for developing functional pasta with improved bioactive potential and acceptable technological and sensory quality.