Shrinkage of strawberries during microwave drying

Strawberries were pretreated with ethyl oleate and sodium hydroxide solutio n to make the skin transparent to moisture diffusion. The treated berries w ere dried with convective air at 45 degrees C and microwaves at two power l evels of 0.1 and 0.2 W/g. During the drying process change in shrinkage rat io with respect to moisture ratio was studied. Also, the change in equivale nt diameter of strawberries in correlation with moisture ratio was investig ated. During drying the variation in surface and centre temperatures with m oisture content and time was studied. It was observed that there is a direc t relation between the shrinkage and moisture ratio. The equivalent diamete r of the berry has a logarithmic function with respect to the moisture rati o.