Process Optimization of Ultrasound-Assisted Osmotic Dehydration of Yellow Cassava Using Response Surface Methodology

Abstract

The process parameters of ultrasound power output (20–100%), osmotic concentration using salt solution (10–30% w/v), and process time (10–30 min) were investigated and optimized for ultrasound-assisted osmotic dehydration of yellow cassava using response surface methodology. The experiment was carried out with ultrasound generator at a fixed frequency of 20 kHz at a room temperature. Box Behnken design consisted of three factors at three levels each which made up to 17 experimental runs were used in the experiment. Two slices of yellow cassava were used per experimental run. The result showed that linear terms of power and concentration had significant effects on water loss, solid gain, and weight reduction. The optimized values that would give minimum solid gain and maximum water loss and weight reduction were time of 10 min, ultrasound power of 100%, and concentration of 20.24% w/v. This gave predicted values of 23.05, 0.58, and 22.90% for water loss, solid gain, and weight reduction, respectively. The optimized values could be useful in the processing of yellow cassava in order to achieve increased shelf life.