Changes in Cell Wall Sugar Neutral Composition Contribute to Apple Texture Loss during Storage among Cultivars

Abstract

Fruit texture affects apples’ quality, consumer preference, and shelf life. The cell wall neutral sugar composition was reported to contribute to apples’ mechanical properties at harvest. However, the contributions of cell wall neutral sugar composition to apple texture loss during storage among different cultivars are still unclear. In this study, six cultivars of the apple fruit were stored at 25 °C for 60 days (i.e., rapid loss of texture: ‘Jiguan’, ‘Yindu’, and ‘Qinguan’; slow loss of texture: ‘Fuji’, ‘Huaguan’, and ‘Cripps pink’). The texture properties, physiological indicators, and expression of cell wall-related genes were investigated every 20 d. The results showed that apple cultivars with rapid texture loss showed a faster loss in flesh hardness and crispness, and a higher level of flesh tightness and pericarp break distance, than the cultivars with slow texture loss. Galactose content showed the closest association with the texture properties among the cell wall neutral sugar compositions. The rapid loss of galacturonic acid content and the expression of MdPG1 were higher in the cultivars with rapid texture loss than in those with slow texture loss. These results indicated that changes in cell wall neutral sugar composition contribute to apple texture loss during storage among cultivars.