Impact of Whole Legume Flour Addition on the Physicochemical, Textural, and Sensory Properties of Greek Fermented Flatbread “Langites”

Langites, a traditional flatbread made from a fermented batter baked at 210°C, was investigated regarding the effects of replacing wheat flour with whole‐grain red lentil or chickpea flour on the physicochemical, structural, textural, and sensory properties of langites. Wheat flour was substituted with each legume flour at 0%, 10%, and 30%, and flour functionality and product quality were comprehensively evaluated. Both legume flours exhibited substantially coarser particle‐size distributions than wheat flour, with median particle sizes (D50) of 321.2  μ m for chickpea, compared with 122.5  μ m for wheat flour. The incorporation of legume flours increased water absorption capacity, reaching 2.56 g/g for chickpea blends and 2.40 g/g for lentil blends, whereas higher water solubility was observed in lentil formulations (4.32%). Flour and product color changed significantly, with color differences ( Δ E ) reaching 23.57 for red lentil and 10.93 for chickpea flour. In langites, increasing legume substitution significantly increased moisture content, hardness, gumminess, and chewiness, whereas cohesiveness decreased from 0.85 to 0.80 in the 30% lentil formulation. Image analysis revealed a marked reduction in the number and uniformity of surface eyes, accompanied by an increase in mean eye diameter from 0.97 mm (control) to 1.29 mm and 1.14 mm in langites containing 30% lentil and chickpea flour, respectively, indicating impaired gluten development and reduced gas retention. Sensory evaluation showed that 10% substitution received good acceptability (7.26–7.59) compared with the wheat control (8.21), whereas 30% substitution significantly reduced acceptance, particularly for lentil flour (4.19). Principal component analysis demonstrated that overall acceptability was positively associated with eye number and sweet‐taste perception and negatively associated with hardness, chewiness, larger irregular pores, and color intensity. Overall, the 10% substitution with whole‐grain legume flour represents a promising formulation with enhanced nutritional value while preserving desirable technological and sensory characteristics.