Dehydration of Malay apple (Syzygium malaccense L.) using ultrasound as pre-treatment

Abstract

This work examined the influence of the ultrasonic pre-treatment prior to air-drying on dehydration of jambo (Syzygium malaccense L.) also known as Malay apple. This study allowed estimate water loss and sugar gain during the pre-treatment and the effective water diffusivity in the air-drying process for jambo subjected to ultrasonic pretreatment. Results showed that during the ultrasonic treatment, in distilled water, the Malay apples lost sugar, so such a pre-treatment stage can be a practical process to produce dried fruits with lower sugar content. The water effective diffusivity increased by 28.1% (best result) after application of ultrasound, which caused a reduction of about 27.3% in the total drying time.