Osmotic dehydration progression in apple tissue II: generalized equations for concentration prediction

In Part I of the present communication, osmotic dehydration experiments at atmospheric pressure were carried out using apple (Granny Smith var.) slice s (20 and 30 mm thick) at 20 degrees C, 30 degrees C, 40 degrees C and 50 d egrees C. The slices were subjected to treatment for varying periods of tim e (0.5, 1, 2, 3, 6, 12, 22 and 34 h) by using a sucrose solution (65% (w/w) as osmotic agent following which, slices, 1.5 mm thick, were obtained to d etermine water and sugar contents throughout the sample thickness. In an at tempt to understand the osmotic phenomena, an approach based on the "advanc ing disturbance front" (ADF) concept was developed. In this second part, generalized equations developed from the concept of AD F have been proposed to describe the kinetics of sample concentration chang es either in terms of concentration profiles or average concentrations. (C) 1999 Elsevier Science Ltd. All rights reserved.