ABSTRACT
The objectives of this study were (i) to evaluate moisture loss (ML), solids gain (SG), moisture loss rate (d(ML)/dt), solids gain rate (d(SG)/dt), effective moisture diffusivity (DeM), and effective solids diffusivity (DeS) during osmotic dehydration (OD), ultrasound-assisted osmotic dehydration (UA-OD), and osmotic dehydration of whole cranberries, preceded by microwave-vacuum pretreatment (MV + OD) or freezing/thawing treatment (F + OD ) and (ii) to use a mathematical model to predict moisture content ML∞ and solids content SG∞ in equilibrium state and the distribution of moisture and sucrose in whole cranberries during dehydration. Microwave-vacuum and OD treatments produced cranberries with the highest values of ML and SG (39.7 and 8.4 g 100 g fresh fruit−1, respectively), d(ML)/dt and d(SG)/dt (76.9 and 8.5 h−1, respectively), DeM and DeS (6.1 and 3.7 × 10−10 m2 s−1, respectively). Azuara’s and Peleg’s models adequately described the OD kinetics of whole cranberries in terms of ML and SG. The results indicate that the equilibrium values of ML∞ and SG∞ were not reached under the conditions specified in the present study.