Osmotic dehydration of Aloe vera (Aloe barbadensis Miller)

Aloe vera possess immunomodulatory, anti-inflammatory, antibacteria effects and wound and burn healing properties, but it is a very unstable product due to its high water content. Osmotic dehydration can be used to obtain stable products from aloe. In this work the effect of osmotic dehydration (OD) on Aloe vera (Aloe barbadensis Miller) leaves was studied. Peeled and unpeeled Aloe vera slices (15 x 50 mm), were immersed in sucrose solutions at 35, 50 and 65 degrees Brix at 25 and 40 degrees C. Moisture, effective diffusion coefficients and mass fluxes (water loss, solids gained and weight reduction) were determined. Osmotic dehydration experiments were conducted at atmospheric pressure. The best conditions for the OD of Aloe slices with the highest effect on diffusivity were obtained using a temperature of 40 degrees C for peeled samples. The analysis of the effect of temperature on mass transfer kinetics showed that unpeeled samples were more effected than peeled samples. (C) 2009 Elsevier Ltd. All rights reserved.