Unveiling the key aroma-active volatiles influencing consumer preferences in typical oriental melon varieties by molecular sensory science methods

Oriental melons, a group of Cucumis melo varieties produced in East Asia, demonstrate considerable genetic diversity in aroma. However, the disparities and complex interrelations between volatiles, sensory, and consumer preferences among varieties remain underexplored. This study systematically evaluates 18 homozygous parental line varieties, harvested in uniform conditions and with optimal maturity to isolate genetic influences. Sensory evaluation classified the varieties into 3 Groups, with fruity aromas showing positive correlations to consumer preference (r = 0.88, p < 0.001) and green aromas exhibiting inverse associations (r = -0.65, p < 0.01). 251 volatiles were identified by comprehensive two-dimensional gas chromatography-olfactometry-time of flight-mass spectrometry (GC×GC-O-TOF-MS), with 35 aroma-active compounds quantified by gas chromatography-mass spectrometry (GC-MS) and standards. Finally, 10 key aroma-active compounds were revealed through orthogonal partial least squares discriminant analysis (OPLS-DA) and odor activity value (OAV). Ethyl acetate (OAV = 5510.54) and octanal (OAV = 645.08) drove Group 3's fruity aroma and high preference, while cis-4-heptenal (OAV = 18,518.39) and cis-6-nonenal (OAV = 6123.92) were linked to Group 1's green aroma and low preference. This research lays a solid groundwork for the evaluation of oriental melon aroma and provides a dependable framework for aroma-focused breeding programs aimed at enhancing consumer satisfaction.