Abstract
As a high-value legume crop, the chemical basis underlying flavor and nutritional quality differences among cowpea (Vigna unguiculata L. Walp., Vu) varieties remains poorly understood, limiting targeted quality improvement. This study integrated headspace gas chromatography-ion mobility spectrometry with ultra-high-performance liquid chromatography-tandem mass spectrometry to comprehensively analyze metabolites in 14 Chinese cowpea varieties. A total of 174 volatile organic compounds were identified, with esters, heterocyclic compounds, and ketones accounting for 51.15% of the total. Principal component analysis and fingerprint clustering revealed variety-specific distribution patterns of volatile components, with the Vu-1 variety showing significant enrichment in β-pinene and 3-pentanol. Metabolomic analysis further identified 392 differentially expressed metabolites, revealing that amino acid metabolism and flavonoid metabolism are the core pathways determining varietal differences. This study systematically elucidates the chemical characteristics of cowpea varieties from a metabolomic perspective, providing important evidence for quality improvement and high-value utilization of legume crops.