Black chickpea landraces as a sustainable protein source: physicochemical, nutritional, and technological properties

Neglected legume landraces represent valuable genetic resources for sustainable food systems, yet their compositional and technological properties remain poorly explored. This study comprehensively characterized the flours obtained from two Sicilian black chickpeas (Cicer arietinum L.) landraces, Rough Black Chickpeas (RBC) and Smooth Black Chickpeas (SBC), focusing on their chemical composition, nutritional profile, and technological properties using standardized analytical methods. Both flours showed a balanced macronutrient profile with significant genotype-dependent variations. SBC exhibited higher contents of protein (20.17 vs. 19.32 g/100 g), dietary fiber (7.14 vs. 6.23 g/100 g), and fat (4.66 vs. 4.36 g/100 g), as well as a higher total mineral content (18.65 vs. 17.84 g/kg) compared to RBC. Conversely, RBC showed higher total carbohydrates (59.34 vs. 57.29 g/100 g) and significantly higher levels of soluble sugars, including fructose (18.37 vs. 12.90 mg/100 g), galactose (17.43 vs. 7.76 mg/100 g), sucrose (85.39 vs. 56.40 mg/100 g), and stachyose (859.08 vs. 574.47 mg/100 g). Both cultivars met the FAO/WHO total essential amino acids requirements (SBC: 613.09; RBC: 649.12 mg/g protein), with methionine as the limiting amino acid (4.26–4.19 mg/g of protein). Phenolic profiling revealed shikimic acid, hydroxybenzoic and cinnamic derivatives, and catechin. Marked differences emerged in technological properties: RBC exhibited higher water absorption, swelling capacity, and emulsion stability, whereas SBC showed a more moderate hydration behavior. Overall, the results demonstrate that technological properties are strongly dependent on compositional and structural factors. These findings support the valorization of black chickpea landraces as sustainable and functional ingredients for innovative legume-based foods, contributing to biodiversity preservation and dietary diversification.