Reuse of sorbitol solution in pulsed vacuum osmotic dehydration of yacon (Smallanthus sonchifolius)

Abstract

The osmotic solution (OS) used in pulsed vacuum osmotic dehydration (PVOD) could represent an environmental problem. The reuse of the solution minimizes the cost, but has to consider the properties of the dehydrated product and the solution itself. The reuse of sorbitol solution, 38 kg/100 kg solution, in 15 successive PVOD of yacon slices (35°C, 300 min) was studied. The evaluation was based on alterations of soluble solids, water activity, pH, turbidity, electrical conductivity, viscosity, density, color, and microbiological stability. The weight loss, moisture content, and soluble solids of the food were also evaluated. Among the OS characteristics, only the color, electrical conductivity, and turbidity of the solution changed significantly, alterations that could be reduced with filtration. The food properties were not significantly affected. The microbiological content was retained in acceptable levels. The reuse of the sorbitol solution could be performed without relevant alterations in the food or the solution.