Chemical, biochemical, and spectral characterization of optimized fermented pulses compared to conventional cooking

The objective was to compare the effects of optimized Lactiplantibacillus plantarum 299v fermentation conditions and traditional cooking on the chemical composition and functional profiles of red lentil (RL), green split pea (GSP), black-eyed pea (BEP), black bean (BB), and pinto bean (PB). An integrated approach evaluated proximate composition, dietary fiber, protein profiles, antioxidant capacity (DPPH), enzyme inhibition (DPP-IV and α-glucosidase), FT-IR/NIR, and metabolomics analyses. Both cooking and fermentation significantly increased DPP-IV inhibition (p < 0.05), with fermentation showing the strongest effect, particularly BEP, RL, and GSP. Fermentation resulted in a higher α-glucosidase inhibition (p < 0.05) compared to cooking. Antioxidant capacity improved only in fermented BB (p < 0.05). Although soluble protein concentration decreased after processing, fermented BB retained the highest levels (p < 0.05). Untargeted metabolomics revealed distinct metabolite changes in response to cooking and fermentation of the pulses. Cooking mainly affected fatty acids, amino acids, and phenolic compounds whereas fermentation increased bioactive metabolites. Fermentation also promoted microbial derived dipeptides and additional fatty acid derivatives compared with raw and cooked samples. Lactic acid fermentation modulated pulse chemistry and enhanced their biological functional properties. While these findings show clear biochemical and functional enhancements, confirming their physiological relevance will be required in vivo and human feeding studies.