Kinetic Modeling of Mass Transfer during Osmotic Dehydration of Ziziphus jujube

Osmotic dehydration of jujube slices was performed to evaluate the influence of solution temperature (30, 40 and 50°C), sucrose concentration (40, 45 and 50% w/v) and sample to solution ratio (1:10, 1:15 and 1:20) on mass transfer kinetics. Modeling of mass transfer kinetics for water loss and solid gain were carried out using Magee, Azuara and Peleg models. Effective moisture and solid diffusivities and activation energy were also determined. The results showed that an increase in sucrose concentration as well as solution temperature led to an increase in water loss and solid gain of jujube samples during osmotic dehydration. Azuara model was the most suitable model to describe the osmotic drying process for both moisture loss and solid gain because of high R^2 values and small values of RMSE and SSE. The effective moisture and solid diffusivities ranged from 2.734 to 5.617×10^− 10 and 3.0828 to 5.964×10^−10 m^2/s, respectively. The results indicated that osmotic solution concentration has a reverse relationship with moisture and solid activation energy.