Influence of Blanching Pretreatment on the Drying Characteristics of Cherry Tomato and Mathematical Modeling

The hot air drying with blanching pretreatment may provide a practical method for the production of dried cherry tomatoes. The influences of drying temperature (50°C, 60°C, 70°C and 80°C) and blanching on the drying kinetics of cherry tomatoes were studied. Nine mathematical models were evaluated and the determination of coefficient ( R 2 ), chi-square ( χ 2 ) and root mean square errors (RMSE) were compared. The Logarithmic model gave best results with R 2 of 0.9992 and 0.9995 for fresh and blanched cherry tomatoes, respectively. The values of effective moisture diffusivity coefficient D eff varied in the range of 1.7281 × 10 −9 to 4.6306 × 10 −9 m 2 s −1 for the fresh cherry tomatoes, while 2.1034 × 10 −9 to 6.6487 × 10 −9 m 2 s −1 for the blanched samples. The values of activation energy were 31.99 and 36.21 kJ mol −1 for the raw and blanched cherry tomatoes, respectively. Furthermore, the effect of temperature and blanching on color change of cherry tomatoes was measured.