Microwave drying and moisture diffusivity of white mulberry: experimental and mathematical modeling

Abstract

The literature surveyed revealed that drying kinetics of white mulberry under microwave treatment has not been investigated. In present study, both experimental study and mathematical modeling on microwave drying of white mulberry was performed. The microwave drying process which reduced the moisture content of mulberry from 3.76 to 0.25 (g water/g dry matter) was carried out at 90, 180, 360, 600, and 800 W in a modified microwave drying set-up. The effects of microwave drying technique on the moisture ratio and drying rate of white mulberry were investigated experimentally. Both the effects of microwave power level (under the range of 90-800W) and initial sample weight (50-150g) were studied. No constant rate period was observed. Mathematical modeling of thin layer drying kinetics of white mulberry under microwave treatment was also investigated by fitting the experimental drying data to eight thin layer drying models. Among the models proposed, Midilli et al. model precisely represented the microwave drying behavior of white mulberry with the coefficient of determination higher than 0.999 and mean square of deviation (χ 2 ) and root mean square error (RMSE) lower than 1.1x10 -4 and 8.9x10 -3 , respectively for all the microwave drying conditions studied. The effective moisture diffusivity (D eff ) of white mulberry varied from 0.45 x10 -8 to 3.25x10 -8 m 2 s -1 . Both the drying constant (k) and D eff increased with the increase of microwave power level.

Effect of Microwave, Infrared and Freeze Drying Methods on Drying Kinetics, Effective Moisture Diffusivity and Color Properties of Turmeric

“…Accordingly, the drying periods were 255, 125 and 65 min for the samples that were dried at 90, 120 and 350 W, respectively. Similarly, the decline in drying periods along with the rise in the microwave power level has also been confirmed for okra (Dadalı et al 2007), pumpkin (Wang et al 2007), white mulberry (Evin 2011) and onion slices (Arslan & Özcan 2010). As expected, the shortest time in infrared drying (120 min) was obtained at 80 °C in comparison with 60 and 70 °C, which required times of 250 and 170 min, respectively.…”

Investigation of drying kinetics and physicochemical properties of mulberry leather (pestil) dried with different methods

“…For the determination of the best model for portraying the drying curve of pestils, seven thin layer mathematical models were utilized. Models name and references were given, respectively, as; Page MR = exp(− kt n ) (Liu et al, ), Modified Page MR = exp [(− kt ) n ] (Toğrul, ), Logarithmic MR = a exp(− kt ) + c (Bhattacharya, Srivastav, & Mishra, ), Lewis MR = exp(− kt ) (Doymaz, ), Henderson and Pabis MR = a exp(− kt ) (Evin, ), Two‐Term Exponential MR = a exp(− kt )+(1 − a ) exp(− kat ) (Ertekin & Yaldiz, ), Wang and Singh MR = 1 + at + bt 2 (Wang & Singh, ).…”

Mathematical Modelling and Determination of Mass Transfer Characteristics of Celeriac Slices under Vacuum Drying

“…As the results show, the Midilli-Kucuk model with average values of RMSE=0.008289 and SSE=0.0002 was found as the best model to describe the drying kinetics of the celeriac slices. Similarly, the Midilli-Kucuk model has been introduced as the best mathematical model to describe microwave drying of white mulberry [19], intermittent drying of rough rice [20], convective solar drying of prickly pear peel [21], convective drying of potato pulp waste [22] and hot air drying of apple slices [1].…”