Germination-Induced Changes in the Nutritional, Bioactive, and Digestive Properties of Lima Bean (Phaseolus lunatus L.)

Abstract

(1) Background: Lima beans (Phaseolus lunatus L.) are underutilized legumes rich in nutrients; however, they are limited by the presence of antinutritional content. In this study, we evaluated the effects of a low-cost germination treatment on the nutritional composition, antinutrient content, and digestibility of whole lima beans. (2) Methods: unlike previous studies focused on common legumes or isolated proteins, this work adopted a whole-seed approach and integrated multiple parameters to provide a comprehensive evaluation. (3) Results: The total polyphenol and flavonoid contents increased significantly, by 215.57 mg GAE/g and 71.84 mg RE/g, respectively, at 72 h of germination (p < 0.05). Antioxidant activity nearly doubled compared to raw beans, while the tannins and phytic acid content decreased significantly (p < 0.05). SDS-PAGE showed that germination enhanced digestibility by breaking down high-molecular-weight proteins into smaller fragments (15–30 kDa). Notably, samples germinated for 12–48 h showed higher digestibility after 2–3 h of limited proteolysis. (4) Conclusions: these findings indicate that germination effectively reduces antinutritional factors and improves digestibility, making processed lima beans a promising nutrient-dense ingredient for food formulations.