The concevitve drying of eggplant slices subjected to ultrasonic pretreatment: Some quality attributes

This study investigated the drying kinetics, color parameters (CIE L*a*b), microstructural properties (SEM and porosimetry), rehydration behavior, and sensory attributes of eggplant slices. These slices were dried at various temperatures (50°C, 60°C, and 70°C) after being subjected to ultrasound pre-treatments of differing intensities. A significant reduction in drying time was observed with increasing temperature, with the fastest mass loss occurring at 70°C. Color analyses revealed that higher temperatures (70°C) led to a decrease in L* values (darkening), while light conditions positively influenced color preservation. SEM and porosimetry data indicated that samples subjected to ultrasound pretreatment (W1) developed a more homogeneous pore structure. In contrast, high-intensity ultrasound (W2) resulted in structural damage. Rehydration studies demonstrated the highest water absorption capacity at 70°C. However, samples dried at 60°C exhibited the best performance in sensory evaluation (an overall acceptability score of 81.11). These findings suggest that a drying temperature of 60°C combined with moderate ultrasound pretreatment (W1) represents the optimal conditions for preserving microstructural integrity, color stability, and sensory quality in eggplant drying processes.