Nutritional evaluation of high-value alternative proteins extracted from legume defective seeds
Camila Jiménez-González, Laura Fernández de Castro, Ana Torrado, Clara Fuciños, Elena Díaz de Apodaca, María L. Rúa
Abstract
The high protein content of legumes, including P. vulgaris, L. culinaris, L. albus, and P. sativum, is increasingly valued in food formulations, driving interest in utilizing their by-products. This study evaluates the nutritional quality and applications of four legume protein concentrates derived from defective seeds. Analysis included amino acid composition, antinutrient presence, and in vitro digestion, along with structural analysis. Proximate composition, pigment, mineral, and bioactivity assays were also conducted. All concentrates surpassed 70 % protein concentration and presented a well-balanced amino acid profile meeting the requirements for healthy individuals. Bean concentrate exhibited elevated levels of trypsin inhibitor (53.27 ± 0.19 TIU/mg) and total phenolic compounds (0.82 ± 0.02 mg GAE/g), while pea concentrate showed the highest phytic acid content (2.67 ± 0.02 %). Bean concentrate displayed superior structural stability and lower in vitro protein digestibility (∼20 %), compared to the other concentrates (60–70 %). These findings optimize legume defective seeds utilization in plant-based products, addressing sustainability and enhancing nutritional value. • Legume by-products isolates offer high protein and balanced amino acid profile. • Phosphorus and potassium emerge as the primary minerals in the isolates. • Lutein and chlorophyll a establish as the predominant pigments. • Presence of antinutrients and phenolic compounds decreases protein digestibility. • Higher structural stability increases protein resistance to digestion.