Unveiling key aroma-active compounds of two distinct aroma-types oriental melon: An integrated sensomics approach utilizing GC × GC-O-TOF-MS, GC-MS, aroma recombination and omission experiments.

Comprehensive two-dimensional gas chromatography-olfactometry-time-of-flight mass spectrometry (GC × GC-O-TOF-MS) is valued for its high resolution, sensitivity, and odor identification in complex food aroma analysis. However, few studies have combined it with sensomics to identify aroma-active compounds in oriental melons. Key aroma-active compounds of two oriental melons (LONG4 and ZHCG) were characterized using optimized headspace solid-phase microextraction (HS-SPME) combined with GC × GC-O-TOF-MS and gas chromatography-mass spectrometry (GC-MS), aroma extraction dilution analysis (AEDA), aroma recombination and omission experiments. 124 volatiles and 32 aroma-active compounds were identified by HS-SPME-GC × GC-O-TOF-MS. Of these, 22 with a high flavor dilution factor (FD > 2) were accurately quantified by HS-SPME-GC-MS. Aroma recombination and omission experiments demonstrated that eight compounds were the key odorants contributing to the fruity and sweet aroma of LONG4, while seven compounds were the key odorants contributing to the grassy and cucumber aroma of ZHCG. This study provides support for aroma-oriented quality control and production of oriental melons.