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The effect of pre-treatment and air temperature on the drying kinetics and some quality criteria of Jerusalem artichoke were investigated. The pre-treated and untreated of Jerusalem artichoke slices were dried in a cabinet dryer at temperatures of 60, 70 and 80 °C. It was found that air temperature and pre-treatment had more significant effects on drying kinetics, color and rehydration ratio. The experimental data were adjusted to seven thin-layer drying models in the representation of vegetable and fruit drying. The Midilli & Kucuk model was best fitted to measurements. The effective moisture diffusivity at each temperature was determined by Fick’s second law of diffusion, in which their value varied from 5.49×10–10 to 1.90×10-9 m2·s-1 over the mentioned temperature range. The values of the activation energy of moisture diffusion were 50.74 and 40.21 kJ·mol-1 for citric acid and control samples, respectively.

Edible mushrooms are foods with high nutritional value, delicious and therapeutic products. The main objective of this research was to investigate the influence of different temperatures of the dehydration process on the microstructure and color of Agaricus bisporus mushrooms. Tray drying conditions were: constant air velocity, 50, 60 and 70 °C suited to relative humidity (RH) values of 12.17, 4.8 and 2.26 % respectively. Mathematical modeling of drying process, effective moisture diffusivity and activation energy calculations were presented. The effective moisture diffusivity was between (1.09665 – 2.11723)·10-10 m2∙s-1 for white and (0.99522 – 1.69885)·10-10 m2∙s-1 for brown mushrooms. The activation energy values indicate a higher energy input for the white mushrooms drying. SEM micrographs revealed the overall integrity of the tissue and some hyphae from the stipes of brown and white mushroom appeared intact and similar. At 70 °C, the presence of these crystals is more emphasis due to calcium.