A comparative analysis of the volatile profiles in the pulp of red-fleshed and standard orange varieties during fruit maturation

Kirkwood Navel and Ruby Valencia red-fleshed sweet oranges accumulate high concentrations of the carotenes phytoene, phytofluene and lycopene in the pulp. In order to gain insight into the parameters that influence fruit quality in these varieties, a comparative analysis of volatile organic compounds (VOCs) in the pulp of Kirkwood Navel and Ruby Valencia red-fleshed sweet oranges and their standard blond counterparts, Navel and Valencia, was performed during fruit development and ripening. A total of 95 VOCs were identified by HS-SPME/GC–MS during the ripening process. The observed differences in VOCs between red-fleshed and blond oranges were more closely related to the fruit ripening stage than to the genotype. However, two distinctive common features were identified in both red-fleshed oranges compared to their respective standard varieties. These were lower levels of sesquiterpenes and higher levels of the norisoprenoids 6-methyl-5-hepten-2-one and geranylacetone. These findings indicate that altered carotenoid metabolism in red-fleshed oranges not only affects flesh pigmentation but also leads to changes in specific VOCs that may influence flavor perception. • Red-fleshed oranges accumulate large amounts of carotenes in the pulp. • Ninety-five volatiles were identified in the pulp of red-fleshed and standard oranges. • Red and standard orange volatiles were affected more by fruit ripening stage than genotype. • Red oranges showed higher levels of specific norisoprenoids and reduced of sesquiterpenes. • Alteration of carotenes in red oranges may affect specific volatiles and fruit aroma.