Raw materials
The matured purple sweet potatoes will be acquired from a local fresh market in Suratthani province, Thailand. The obtained raw materials will be thoroughly cleaned using tap water, and then, hand peeled and cut into slices (~1.5 cm cubes) using a knife. The sliced potatoes will be washed in drinkable water, thoroughly wiped the excessive water with a paper towel and proceeded to osmotic dehydration treatment. Commercial food grade sucrose and salt (CaCl2) will be used as osmotic agents for this study.