Evaluation of high intensity ultrasound pre-treatment effects on the physical properties and bioactive compounds of convective dried quince samples

Abstract

This work was undertaken to evaluate the impact of high-intensity ultrasound (HUS) pre-treatment on some quality characteristics of convective-dried (CVD) quince fruit pieces at different temperatures (50, 60, 70, and 80 °C). CVD quince samples at 70°C with a 15 min HUS pre-treatment showed the lowest water activity (0.36 ± 0.02). On the other hand, the quince fruit samples exposed to 15 min HUS pre-treatment shrank significantly (P < .05) especially when combined with convective drying at 70°C. The dried quince samples with no HUS pre-treatment exhibited the most condense and denser porous texture. While the lowest antioxidant capacity (AOC) was described for dried quince samples at 50°C with no HUS pre-treatment (2.58 μmol TE/g dry–weight), the highest AOC was determined for the dried quince samples exposed to HUS pre-treatment for 15 min at 70 °C (7.08 μmol TE/g on dry basis). Among the HUS-treated quince samples, the highest vitamin C content was found for the CVD quince samples at 70°C with 15 min HUS pre-treatment (43.79 mg/100 g on dry weight.). In overall, HUS is a promising pre-treatment as shown in current work by its efficiency for better preservation of CVD quince quality in terms of physical and chemical characteristics.