Differential sensitivity to thermal processing of two muskmelon cultivars with contrasting differences in aroma profile

The muskmelon aroma is delicate, but unacceptable off-notes can be formed during thermal processing, impeding the muskmelon industrial applicability. To investigate cultivar differences in the thermal sensitivity of their aroma, heat-induced aroma alterations of muskmelon cultivars with different aroma profiles and post-harvest physiologies were comparatively studied using qualitative descriptive analysis, headspace-gas chromatography-ion mobility spectrometry, and a gas chromatography-olfactometry/modified frequency (MF) method. Higher intensities of "fermented" and "sulfurous" off-notes were observed in a non-climacteric Queen muskmelon (QM) compared to a climacteric Xizhoumi No. 25 muskmelon (XM). The number and MF values of odorants in QM and XM increased after heating. However, less agreeable odors and more off-flavors with higher MF values were identified in heated QM compared to XM. Both sensory and instrumental analysis revealed different thermal sensitivities between the muskmelon cultivars, which indicated that XM was better at retaining its original aroma and inhibiting the development of off-odors. This study provides theoretical guidance for muskmelon resource utilization and also promotes the muskmelon deep-processing products and growth in the muskmelon market.