Effect of Moisture Content on Diffusion Coeffkient in Osmotic Dehydration of Pineapple Core

Abstract

Effective diffusivity of water in pineapple core was determined by using twopieces of pineapple core with different moisture content. The two pieces were made tocontact at a transverse surface area. After contacted for a given period , both were slidedinto further smaller pieces. Water content were then measured to obtain concentrationprofile, a subsequent comparison with theoretical prediction provided the effectivediffusivities of water. The effective diffusivities of water in pine apple core with watercontent of 0.699 to 3.951 gm./gm.solid were found in range between 9.0454x10^-11 to 4.1045x10^-10 m²/s. The correlation coefficient showed that the water content hadno effect on effective diffusivities of water. The diffusion process in this system mightbe molecular diffusion more than osmotic diffusion that shown in apple and pineapple.