Selection of ripeness stages for hot-air drying of peaches based on drying characteristics and physicochemical properties

The aim of this research was to systematically evaluate the impact of varying ripeness stages (categorized into five distinct levels: I, II, III, IV, and V) on the drying behavior, moisture status, cellular injury, texture, rehydration properties, bioactive compounds, antioxidant activities, and sensory attributes of peaches. The ultimate goal was to identify the optimal ripeness stage of peaches for hot-air drying. Results demonstrated that significant disparities exist in drying characteristics among peaches of different ripeness levels. Peaches at ripeness stage III exhibited the most efficient drying kinetics, characterized by the shortest drying duration, highest drying rate, and maximum moisture diffusion coefficient. This was followed by peaches in stages II, I, IV, and V, the differences being attributed to variances in moisture mobility, content, and cellular injury. Additionally, stage III peaches displayed optimal levels of ascorbic acid, total phenolics, antioxidant capacity, and rehydration ratio. Conversely, peaches at stage V excelled in visual appearance, sugar-to-acid ratio, and flavor profile. Consequently, peaches at ripeness stage III are recommended for hot-air drying due to their superior drying efficiency and quality attributes. This study serves as a theoretical foundation for future work on quality categorization and drying methodologies for peaches.