Untargeted metabolomics analysis of Gannan navel orange at different storage periods under room temperature using HS-SPME-GC-MS and UPLC-Q-TOF/MS

Navel orange remains metabolized continuously during postharvest storage, but few studies have monitored the changes of these metabolites. Therefore, HS-SPME-GC-MS and UPLC-Q-TOF/MS were used to comprehensively investigate the dynamic changes of the components of Gannan navel orange during storage at room temperature. A total of 62 volatile components and 68 non-volatile components were identified. Principal Component Analysis and Partial Least Squares Discriminant Analysis showed that navel orange under different storage periods were clearly distinguished. Combined with VIP > 1 and p < 0.05, 19 volatile and 27 non-volatile differential metabolites were obtained. KEGG enrichment analysis revealed that flavonoid biosynthesis (map00941) was the primary metabolic pathway. The middle storage period had a higher antioxidant enzyme activity, but the malondialdehyde content was the opposite. These results reveal the changes of postharvest components of Gannan navel orange, providing a theoretical basis for the storage and product development of navel orange.