DESHIDRATACIÓN OSMÓTICA DE CASTAÑA EN MEDIOS ESTÁTICOS Y DINÁMICOS DE SAL, SACAROSA Y GLUCOSA OSMOTIC DEHYDRATION OF CHESTNUT USING STATIC AND DYNAMIC MEDIA OF SALT, SUCROSE AND GLUCOSE

Abstract

Chestnut fruits were submitted to osmotic dehydration in sodium chloride (17, 22, 26.5% w/w), sucrose (40, 50, 60% w/w) and glucose (40, 50, 56.5% w/w) solutions at different stirring rates (0, 40, 110 rpm) and periods of time (1, 2, 4, 8 h) at 20 °C. The effect of temperature (50 °C) was studied in the case of samples dehydrated with glucose solutions. Several parameters for each dehydration process such as solids gain, water loss, and its corresponding ratio and weight reduction, were determined. High stirring rates increased solids gain and decreased water loss and its ratio, especially in the case of solutions of high viscosity. Moisture and solids gain contents were modelled by Hawkes and Flink equation for short times and water and osmotic solute transfer coefficients were calculated. The corresponding effective coefficients of diffusion were also evaluated by means of Fick's law. © 2008 SOMENTA.