Evaluation of the mechanical properties and diffusion coefficients of osmodehydrated melon cubes

The objective of this work was to evaluate the influence of osmotic agents, their concentration and temperature, on the mass transfer kinetics and mechanical properties of osmodehydrated melon cubes. Samples were immersed in a hypertonic solution of sucrose or maltose up to 8 h under controlled temperature and agitation. Water loss, sugar gain and mechanical properties were analysed throughout the process. Mass transfer kinetics was modelled according to Peleg and Fick equations. Higher water loss, lower sugar uptake and stress at rupture values more similar to fresh fruit were observed in samples treated with maltose solutions. Peleg's model showed the best adjustment to all the experimental data, however the k(1) and k(2) parameters did not show a clear trend with the solution concentration or temperature increase. The effective diffusivity obtained using Fick's equation varied from 3.93 x 10(-9) to 6.45 x 10(-9)m(2) s(-1) for water loss and from 7.57 x 10(-10) to 3.14 x 10(-9)m(2) s(-1) for sugar gain.43112065207