Prediction of water and soluble solids concentration during osmotic dehydration of mango

The objective of this work was to develop a mathematical model to predict the kinetics of the change in water and soluble solids fractions in mango (cv. Haden) osmotically dehydrated in a sucrose solution. A full factorial design at three levels was used, varying temperature (T) and concentration of soluble solids in the osmotic solution (SSC). The models based on the Weibull distribution were built up in two steps: (i) primary models to determine the kinetic parameters at constant T and SSC, (ii) secondary models to further include the influence of T and SSC on the parameters of the primary model. The Weibull model can successfully describe both water and sugar fractions during osmotic dehydration (R-2 = 0.98 and 0.96, respectively for water and sugar models). The time constant (T) for both models followed an Arrhenius-type relationship with temperature, with the reference time constant (tau(ref)) at the average T and increasing linearly with SSC. The shape factor (0) was constant. The prediction accuracy of the models to predict water and sugar fraction was tested by cross validation and using a third set of experimental data, showing very good results with shrinkage values below 4.6% and errors on predictions lower than 1.6%. (C) 2007 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.