Ultrasound-Assisted Air-Drying of Apple (Malus domestica L.) and Its Effects on the Vitamin of the Dried Product

This work has examined the influence of ultrasonic-assisted air-drying on the dehydration of apple (Malus domestica L. var Royal Gala) and its influence in the availability of vitamins A, B-1, B-2, B-3, B-5, B-6, and E of the dried product. This study also has estimated the effective water diffusivity in air-drying process subjected to ultrasonic waves. The water effective diffusivity increased by up to 79 % by ultrasound application, which caused a reduction of about 35 % in the total drying time compared to the air-drying without sonication. The application of ultrasound increased the availability of vitamins B-1, B-2, B-3, and B-6 in the dried product. A loss of vitamins B-5 and E were observed for all studied drying conditions.