Assessment of the color attributes of quince slices affected by microwave drying method and pretreatments using image processing approach

This study focused on evaluating the influence of various pretreatments and microwave power levels on the drying behavior and color attributes of quince slices. In this context, quince slices were either pretreated with ultrasound, tangerine juice, or ascorbic acid, or left untreated (control), and then dried in a microwave at 300, 600, or 900 W. The color properties (L, a, b) of the fruit slices were determined by an image processing technique. In the study, the shortest drying time was determined to be 12 min at 900 W with ascorbic acid pretreatment. However, 900 W-ascorbic acid treatment gave the lowest total energy consumption (0.15 kWh). The highest values of the L, a, and b parameters determined by image processing were obtained in the 300 W - ascorbic acid (77.83), 600 W - control (15.40), and 600 W - ascorbic acid (52.37) treatments, respectively. The highest total color change was recorded in the 600 W - ascorbic acid (55.33) treatment. Tangerine juice caused an increase in redness in the product color. Ascorbic acid pretreatment effectively enhanced drying efficiency, minimized energy consumption, and preserved the color quality of quince slices. Pretreatments accelerated drying and minimized energy consumption. The color characteristics of the pretreated samples were better preserved than those of the control group (no pretreatment). While the drying rate was initially high, it decreased as the products lost moisture. In line with the findings, future studies are needed to develop new pretreatment strategies that optimize drying time, maintain color stability, and improve product quality, and to develop new pretreatment strategies for different fruit species.