Juice volatile composition differences between Valencia orange and its mutant Rohde Red Valencia are associated with carotenoid profile differences.

A targeted approach using HS-SPME-GC-MS was performed to investigate volatile compounds of ordinary Valencia (VAL) and its more deeply colored mutant Rohde Red Valencia orange (RRV) at different developmental stages. Fifty-six volatile components classified into six chemical groups were quantified. The individual volatile compounds in each group were significantly influenced by the genotype and harvest date. Cluster analysis suggested two principal clusters. Cluster I included fruits of VAL and RRV harvested in July, September, and November and was characterized by the 2-ethyl-1-hexanol acetate and linalool chemotype; cluster II included fruits harvested in January and March, with the valencene/β-myrcene chemotype. Principal component analysis confirmed that fruits of both cultivars harvested at different dates possessed a unique aroma active profile, especially, the odor-active volatile-norisoprenoids degraded from C40 carotenoid were significantly higher in RRV than in VAL at full maturity. These results could provide information for further study of the flavor metabolism pathways in the two closely related cultivars.