The moisture content of the fresh and osmotic dehydrated purple sweet potatoes will be determined by drying at 70ºC for 24 hr in an oven (AOAC, 1984). The water loss of the samples will be calculated as the total moisture content of the fresh samples after osmotic dehydration based on the initial sample mass. WL of samples will be calculated using the following equation and the data will be expressed in percentage.
WL (%) = [(Mi-Mo)/Wi)] x 100
In which Mi is the initial moisture content (g); Mo is the moisture content of osmotically treated samples (g); Wi is the initial total sample mass (g).