Effective moisture diffusivity prediction in two Portuguese fruit cultivars (Bravo de Esmolfe apple and Madeira banana) using drying kinetics data

Abstract

Air convective dehydration was performed at various temperatures (35 °C, 40 °C, 45 °C and 50 °C) using two types of fruits cultivars produced in different regions of Portugal: the Bravo de Esmolfe apple, from the Beiras province, and the Cavendish banana, from Madeira Island. The data collected were used to predict the effective moisture diffusion, which is a crucial input parameter in drying modeling and design. As expected, the values obtained in both falling drying rate periods detected for apples increased with an increase in drying temperature. The effective moisture diffusion in apples varied from 1.968 × 10-10 m2 s-1 at 35 °C to 4.013 × 10-10 m2 s-1 at 50 °C, for the first falling drying rate period, and from 0.9567 × 10-10 m2 s-1 at 35 °C to 3.328 × 10-10 m2 s-1 at 50 °C, for the second period. The dependence of effective moisture diffusion on temperature for bananas is similar, ranging from 1.572 × 10-10 to 2.627 × 10-10 m2 s-1 as the drying temperature changed from 35 to 50 °C.