Mathematical modelling of hot-air drying of osmo-dehydrated nectarines

M.M. RODRÍGUEZ; R. H. MASCHERONI; A. QUINTERO RAMOS

INTERNATIONAL JOURNAL OF FOOD ENGINEERING

BERKELEY ELECTRONIC PRESS

Lugar: N.Y.; Año: 2015 vol. 11 p. 533 - 545

1556-3758

The influence of osmotic pretreatment onnectarines with solutions of glucose syrup and sorbitoland subsequent dehydration at different temperatures(60 °C, 70 °C, or 80 °C) was evaluated. The kinetics ofmoisture loss during drying was obtained and mathematicalmodels were adjusted to estimate the kinetic parameters.Effective diffusion coefficients were calculatedusing Fick?s second law. All drying kinetics exhibitedonly a falling-rate period during hot-air drying owing tomoisture loss in the osmotic pretreatment. Moisture losswas favoured by the use of sorbitol, whereas the diffusivityof water increased when glucose was used as anosmotic agent. Logarithmic and Midilli et al. models bestdescribed the changes in moisture over time, whereasFick?s second law estimated water diffusion coefficientvalues between 4.9610−9 and 2.4310−8 m2 s−1. Thesemodels may be employed to predict the optimum conditionsfor osmo-dehydrating nectarines under hot-air dryingat the industrial level.