Sweet cherry (Prunus avium L.) vacuum drying: Kinetics modelling and textural properties

Sweet cherries ( Prunus avium L.) were vacuum dried at different temperatures in the range between 50 and 70  o C and different pressures between 20 and 200 mbar. Seven mathematical models (Henderson-Pabis, Modified Henderson-Pabis, Simplified Fick’s diffusion, Peleg, Logarithmic, Two term and Midilli et al. ) were used for description of the vacuum drying process and the Midilli et al. model was selected as the most suitable with the highest mean value of coefficient of determination ( R 2 =0.9985) and the lowest mean values of the average absolute relative deviation (AARD=0.90 %), root mean square error (RMSE=0.0061) and the reduced chi-square ( χ 2 =0.0001). Seven textural properties (shear force, penetration force, hardness, springiness, cohesiveness, gumminess and chewiness) were investigated in all dried sweet cherry samples. The results indicated that the pressure influenced the textural properties of sweet cherries during vacuum drying since the minimum values of all investigated texture properties were obtained in samples dried at the pressure of 200 mbar, while the maximum values were obtained at 20 and 65 mbar. It also was noticed that the temperature influenced the textural properties in the temperature range investigated, but not as significantly as it was the case of the pressure influence.