Effect of microwave pre-treatment on air-drying orange (Beauregard) kumara slices

The effects of slice thickness, microwave pre-treatment, and drying temperature on drying orange kumara slices were investigated. The highest drying rate, with minimal loss of colour, occurred at 80°C. Slice thickness did not significantly influence colour but drying time increased with slice thickness. The drying curves fitted the Page thin-layer drying model. Two minutes microwave pre-treatment significantly reduced overall drying time and improved colour but increased shrinkage