Selecting elite cowpea lines for food applications: nutritional composition, phenolic bioaccessibility, and proof-of-concept application in a cake model

Cowpea is a nutrient-dense legume with strong potential for breeding and ingredient development, yet elite-line selection is often based on isolated traits rather than integrated nutritional–functional performance. This study proposes a nutrition-oriented multicriteria screening framework to rank three elite cowpea lines by integrating proximate composition (protein, total dietary fiber, starch and moisture), mineral profile, total extractable polyphenols and phenolic-related antioxidant indicators. Criteria were combined by a block-weighted Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) approach and ranking robustness was tested under alternative weighting scenarios. MNC04-792 F-146 showed the best overall performance and remained first in all sensitivity tests, driven mainly by its superior phenolic-related block. To add post-digestion relevance, phenolic bioaccessibility of the selected line was assessed using the INFOGEST in vitro digestion model, showing a marked reduction in the oral phase followed by near-complete intestinal recovery, with 99.14% retention of the initial total extractable phenolics. As proof of concept for food application, cakes containing 5%, 10% and 15% flour from the selected line were produced. The 5% formulation preserved specific volume and density comparable to the control while improving nutritional density, providing the best balance between enrichment and trained-panel overall quality. Overall, this framework enables robust selection of elite cowpea lines by linking plant food composition to post-digestion behavior and practical applicability in a food matrix.