Integrated Metabolomics and Flavor Profiling Provide Insights into the Metabolic Basis of Flavor and Nutritional Composition Differences Between Sunflower Varieties SH363 and SH361

Sunflower (<i>Helianthus annuus</i> L.) seeds exhibit variation in flavor and nutritional quality. In this study, we combined metabolomics (UPLC-MS/MS and GC-MS) with nutritional analysis and a database-driven flavoromics approach to elucidate the biochemical basis of quality differences between sunflower varieties SH361 and SH363. A total of 1448 seed metabolites were identified, with 242 varying between varieties (predominantly flavonoids and terpenoids). Based on the known aroma descriptors of identified metabolites, we inferred that SH363 would have a more intense nutty-aromatic flavor, whereas SH361 would be characterized by a predominantly sweet taste. SH363 seeds also contained ~50% oil (versus ~24% in SH361) and lower sugar content, indicating an inverse oil-sugar balance that is associated with more complex flavor notes. Lipids and aromatic terpenoids were identified as likely key contributors to SH363's richer flavor profile. Overall, although limited to two genotypes, this work provides new insights into the metabolic basis of sunflower seed flavor differences and supports a conceptual model of lipid-associated flavor enhancement. These findings offer valuable guidance for breeding programs aimed at improving sunflower seed flavor and nutritional quality.