Abstract:To understand the volatile aroma compounds in Xiangyu pumpkin fruit, and the characteristics of the main aroma contributors at different development stages of fruit, this study used electronic nose and head space solid-phase micro-extraction (HS-SPME) combined with gas chromatography (GC)-mass spectrometry (MS) to analyze the volatile compositions in both Xiangyu pumpkin and non-Xiangyu pumpkin resources. Significant differences in aroma trait were found by electronic nose between Xiangyu pumpkin and non-Xiangyu pumpkin. A total of 31 volatile aroma compounds were identified in mature fruit of Xiangyu pumpkin using HS-SPME/GC-MS. Subsequently, GC-MS and mass profiler professional were used to analyse the differences in volatile compounds between Xiangyu pumpkin and two kinds of mature non-Xiangyu pumpkin, and the obtained results revealed significant differences in volatile compounds (which was consistent with those obtained by electronic nose analysis). And 2-acetyl-1-pyrroline (2-AP) was the unique volatile compound in Xiangyu pumpkin as compared with the two sets of control samples (non-Xiangyu pumkins). Finally, the changing trends of 2-AP at different fruit development stages of unpollinated fruit, fruits collected at the 25th day and 55th day, respectively, after pollination. And unpollinated fruit and fruit obtained at the 25th day after pollination had a similar amount of 2-AP, while the 2-AP content deceased significantly in fruit at late maturity stag. This study has laid the foundation for future studies on aroma trait in Xiangyu pumpkin.
