Osmotic dehydration of zucchini and cherry

In this study, osmotic dehydration process on zucchini (Cucurbita pepo), and cherry (Malpighia punicifolia) was investigated.The effect of osmotic dehydration and osmotic dehydration with ultrasound effect in different salt (NaCl) concentrations (5, 15, and 25 %) and temperatures (15, 25, and 35°C) for different lengths on zucchini was evaluated. Responses of water loss (WL), solid gain (SG) and weight reduction (WR) were evaluated. Water loss was linearly affected by salt concentration and immersion time. The influence of temperature was found to be highly insignificant (p<0.05). Response Surface Methodology (RSM) was used to study the effect of temperature, concentration and time factors which influence the responses. First and second degree polynomial models were fitted to data. Ultrasound affected mass transport during osmotic dehydration increasing both water losses and solute gains.Cherry was osmotically dehydrated in various sucrose concentrations (40, 55, and 70 %). Responses of water loss (WL), solid gain (SG) and weight reduction (WR) were evaluated. First and second degree polynomial models were fitted to data for studying the effect of concentration and time. Osmotic treatment of cheryy prior to air drying was also studied.The drying curves obtained from drying experiments were used for the determination of water effective diffusion coefficients.Keywords: osmotic dehydration, air drying, cherry, zucchini, water loss, solid gain and weight reduction.