Relationship between skin greasiness and cuticular wax in harvested "Hongro" apples

We investigated the ripening and skin greasiness of "Hongro" apples during storage at 20 °C. Postharvest treatment using 100 μLL^-1 ethylene accelerated ripening and increased greasiness, whereas treatment using 1 μLL^-1 1-methylcyclopropene delayed ripening and reduced greasiness. Scanning electron microscopy showed changes in cuticular wax structure linked to greasiness. Metabolic analysis identified specific metabolites related to greasiness, which varied upon postharvest treatment. Greasiness was positively associated with ethylene production and butyl-9,12-octadecadienoate content. Random forest modeling predicted greasiness levels with high accuracy, with root mean square error values of 0.322 and 0.362 for training and validation datasets, respectively. These findings illuminate the complex interplay between postharvest treatment, apple ripening, wax composition, and skin greasiness. The application of predictive models exemplifies the potential for technology-driven approaches in agriculture and aids in the development of postharvest strategies to control greasiness and maintain fruit quality.