Kinetics of osmotic dehydration of orange slices using healthy sweeteners

Abstract

Orange slices have been osmotically dehydrated using as osmotic agents new healthy sweeteners: isomaltulose, oligofructose and aqueous extract of stevia. A kinetic study was done by analyzing changes in the water activity, total mass, mass of water and mass of soluble solids in orange slices, depending on the combination of sweeteners used in syrups (A: 30% isomaltulose and 70% of water; AS: 30 % of isomaltulose, 35 % aqueous solution with 1% of stevia and 35% water; B: 20 % isomaltulose, 20 % oligofructose and 60 % water and BS: 20 % isomaltulose, 20 % oligofructose, 30 % aqueous solution with 1% of stevia and 30% water). The results showed that the incorporation of stevia in syrups increased total mass and water mass losses of orange slices. Besides, by fitting second Fick¿s law effective diffusivities have been obtained in order to estimate the time to reach different concentrations of soluble solids in orange slices