Study On Cuticular Wax Greasiness Of ’Pink Lad’ Apple Fruit

Apple fruit is coated with a layer of cuticular waxes. Greasiness which severely bringsdown the economic value of apple fruit is a physical and chemical fruit-surfacephenomenon developing during apple ripening and storage and is associated with changesof cuticular waxes. In this study,‘Pink Lady’ apple fruits were treated with1-methylcyclopropene and then stored at the ambient temperature storage. To provide atheoretical basis for further research of apple fruit greasiness, during storage, we study thechanges of greasiness; cuticular wax morphology and cuticular wax content were measured;at the same time, we explored the changes of cuticular wax composition. The results are asfollows:1. Greasiness of controlled apple fruits occurred at14d after postharvest storage, andgreasiness level increased during storage. Greasiness was found on carpopodium aroundfirstly, calyx around lastly.2. Greasiness was a phenomenon of fruits ripening.1-MCP treatment could maintainfruit quality and delay senescence. For fruits treated with1-MCP, changes of greasinessrevealed a decreasing trend.3. Greasiness was resulted from cuticular wax content and morphology. There wasextremely significant positive correlation between greasiness and cuticular wax content;meanwhile, cuticular wax morphology was changing with wax platelets healing.4. Cuticular waxes generally consisted of various hydrocarbons, fatty acids, esters andalcohols. Hydrocarbons could prevent water loss which didn’t pass through stoma. Thesecondary alcohol nonacosan-10-ol was the most abundant component of alcohols, whichcould be associated with greasiness.