Establishing quality evaluation standards for pomelo fruit: The role of harvesting time and appearance characteristic

The postharvest quality of pomelo fruit is pivotal in determining its market competitiveness and ensuring consumer satisfaction. However, a unified set of quality control standards for pomelo is lacking. This study analyzed a dataset comprising 1681 fruit samples using 21 indicators (6 appearance characteristics and 15 internal qualities) across the entire pomelo harvest period in southeastern China. The findings indicated that the peak flavor quality was achieved during the mid-harvesting period. In contrast, the best nutritional quality was typically found in the early harvesting period within the same growth season. Correlation analysis highlighted significant associations between appearance characteristics (color values a*, fruit shape index, and density) and most internal quality indicators. Using a random forest model to predict flavor and nutritional quality based on appearance yielded R2 values from 0.21-0.41 and 0.01-0.18, respectively. These results emphasized the critical role of harvesting time and appearance characteristics in assessing pomelo quality and presenting a nondestructive and cost-effective approach to improving postharvest handling and market competitiveness. Furthermore, the insights derived from this study provide a valuable framework for enhancing the grading and sustainability of large fruit varieties other than the pomelo.