Fruit Quality and Antioxidant Activities of Yellow-Skinned Apple Cultivars Coated with Natural Sucrose Monoesters

Yellow-skinned ‘Tsugaru’, ‘Summer King’, and ‘Shinano Gold’ apples (Malus × domestica Borkh.) were coated with a mixture of edible sucrose monoesters of fatty acid and ethanol that had never been applied in those apple fruits, for up to 28 days after room temperature storage (DAS) to evaluate their morphological characteristics, fruit qualities, and antioxidant concentrations. The coating treatment significantly reduced respiration rates of ‘Tsugaru’ and ‘Summer King’ apples at both 14 and 28 DAS, and ‘Shinano Gold’ at 28 DAS. The coated ‘Tsugaru’ and ‘Summer King’ apples were found in greater coverage with fragments of the sucrose esters than those of ‘Shinano Gold’, exhibiting greater skin greasiness and thickness. The coated ‘Tsugaru’ and ‘Summer King’ apples mostly maintained high fruit firmness, peel color, vitamin C, total polyphenol concentrations, and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. The recent developed coating material contributed to improving shelf-life of the ‘Tsugaru’ and ‘Summer King’ apples and fruit defense systems as a novel post-harvest technology for sustainable food security.