scholarly journals Mathematical modelling of diced konjac corms drying in a fluidised bed dryer

2020 ◽  
Vol 24 (5 Part A) ◽  
pp. 2833-2843
Author(s):  
Montree Montreepila ◽  
Nattapol Poomsa-Ad ◽  
Lamul Wiset
Keyword(s):  
Fluidized Bed ◽  
Native Species ◽  
Linear Regression Analysis ◽  
Moisture Diffusivity ◽  
Drying Kinetics ◽  
Moisture Loss ◽  
Effective Moisture Diffusivity ◽  
Fluidised Bed ◽  
Effective Moisture ◽  
Kinetics Of

Konjac glucomannan (KGM) can be obtained from tubers (called corms) of various species within the Amorphophallus genus. Among the most popular species for use in food industry is Buk Nuea Sai (Amorphophallus muelleri), a native species in Thailand. Drying process can be helpful in preserving KGM during long storage periods. However, the existing drying systems are often slow and lead to drying delays and subsequently quality reduction of the dried product. Given the economic importance of KGM, new, more efficient drying systems, have to be developed. The present study focuses on the drying kinetics of konjac dices in a fluidized bed, operating at a constant air velocity of 2.5 m/s and air temperatures of 50, 60, and 70?C. Six empirical mathematical models were selected to describe and compare the drying characteristics of konjac dices subjected to these conditions. The model coefficients were determined by non-linear regression analysis. Among the tested models used to describe the drying kinetics of konjac dices, the two-term model was found as the best one. The moisture loss from the dice was described by the Fick?s diffusion equation, and based on the obtained results the effective moisture diffusivity was estimated, getting a value in the range between 9.60526 ? 10?9 m2/s and 1.2006 ? 10?7 m2/s. The relationship between the temperature and the effective moisture diffusivity was described adequately by means of Arrhenius-type equation. An activation energy value between 8.65 kJ/mol and 61.28 kJ/mol was obtained. The findings allow the successful simulation of konjac dice drying in a fluidized bed between 50 and 70?C, 30-60 mm bed height and 6-15 mm dice thickness.

An Experimental Study on the Drying Kinetics of Castor Bean Fruits (Ricinus communis L., “Brs Energia” Variety)

2016 ◽  
Vol 369 ◽  
pp. 119-124
Author(s):  
E.M.A. Pereira ◽  
J.V. Silva ◽  
J.P.S. Santos ◽  
T.H.F. Andrade ◽  
A.G. Barbosa de Lima
Keyword(s):  
Experimental Study ◽  
Castor Bean ◽  
Moisture Diffusivity ◽  
Drying Kinetics ◽  
Effective Moisture Diffusivity ◽  
Effective Moisture ◽  
Air Temperatures ◽  
Thin Layer Drying ◽  
Drying Behavior ◽  
Kinetics Of

This work aims to conduct an experimental study of the drying kinetics of castor bean fruits (Ricinuscommunis L., “BRS Energia” variety). Experiments were conducted using an oven at air temperatures 50 and 70°C and air relative humidity values 16.34 and 6.24%, respectively. The castor bean fruits were considered as a triaxial spheroid. The experimental moisture content data as a function of time were fitted to different lumped models (namely Henderson and Pabis, Page, Midilli and two-term exponential models) available in the literature.The values of the effective moisture diffusivity were obtained from the Fick's diffusion model. Results shows that the two-term drying model could adequately describe the thin layer drying behavior of castor bean fruit, and that the effective moisture diffusivity increases with increasing drying air temperature.

scholarly journals Mathematical modeling and effect of blanching pretreatment on the drying kinetics of Chinese yam (Dioscorea opposita)

2015 ◽  
Vol 21 (4) ◽  
pp. 511-518 ◽  
Author(s):  
Sheng Fang ◽  
Li-Ping Wang ◽  
Ting Wu
Keyword(s):  
Model Performance ◽  
Moisture Diffusivity ◽  
Drying Kinetics ◽  
Effective Moisture Diffusivity ◽  
Diffusivity Coefficient ◽  
Drying Time ◽  
Chinese Yam ◽  
Effective Moisture ◽  
Dioscorea Opposita ◽  
Kinetics Of

The influences of blanching pretreatment on the drying kinetics of Chinese yam (Dioscorea opposita) slices were investigated. Drying experiments were carried out at 60, 70, 80 and 90?C. Six thin layer models were evaluated and the determination of coefficient (R2), chi-square (?2), root means square error (RMSE) were used to analysis the model performance for both raw and blanched samples. The Wang and Singh model gave best results with R2 of 0.9987 and RMSE of 0.0136 for raw yam slices, and R2 of 0.9989 and RMSE of 0.0119 for blanched samples. The effective moisture diffusivity coefficient Deff varied in the range of 0.7295?10-9 to 2.4087?10-9m2 s-1 for raw slices, and 1.3748?10-9 to 3.8524?10-9m2 s-1 for the blanche dones. The activation energy of yam slices drying were 41.149 and 33.499 kJ mol-1 for raw and blanched yam slices, respectively. Results show that blanching pretreatment can reduce the total drying time and improve the effective moisture diffusivity compared with the raw samples.

Drying Kinetics of Grape Stalk

2006 ◽  
Vol 258-260 ◽  
pp. 225-230 ◽  
Author(s):  
J.V. García-Pérez ◽  
M. Blasco ◽  
J.A. Cárcel ◽  
G. Clemente ◽  
A. Mulet
Keyword(s):  
Mass Fraction ◽  
Moisture Diffusivity ◽  
Diffusion Models ◽  
Drying Kinetics ◽  
Effective Moisture Diffusivity ◽  
Effective Moisture ◽  
Mass Load ◽  
Mass Fractions ◽  
The Individual ◽  
Kinetics Of

Grape stalk may be considered as an agro-food byproduct of the wine industry, being considered as a potential source of antioxidant compounds. Actually, before the extraction of antioxidants a previous stage of drying would be necessary. Stalks obtained from a red wine processing (Vitis vinifera var. Bobal) were characterized as a cylinder net with different size ending in spheres. The average diameters and mass fractions of the individual parts of the stalk were measured: spheres (4.4±0.7 mm and 0.352 mass fraction), large cylinders (3.3±0.6 mm and 0.204 mass fraction), intermediate cylinders (2.1±0.4 mm and 0.294 mass fraction) and small cylinders (1.1±0.3 mm and 0.150 mass fraction). Drying kinetics of each one of the parts of the stalk were carried out at 40 °C and 2 m/s using an initial mass load of 30 g. Furthermore, drying experiments of the whole stalk were conducted at the same experimental conditions. Different diffusion models were considered to predict the drying kinetics for each one of the individual parts of the stalk according to the geometry considered. A diffusion model for the whole stalk was developed by adding the individual diffusion models weighed by the corresponding mass fractions. The diffusion models considered fitted properly the drying kinetics of the individual parts considered on the stalk. The figures of the effective moisture diffusivity identified for the different kinds of cylinders were close (1.07-1.78 10-11 m2/s), however, the spheres showed a different behavior characterized by a significantly higher figure of effective moisture diffusivity (3.92 10-8 m2/s). Finally, the usefulness of the model considered to describe the drying kinetics of the whole stalks was shown.

Microwave Drying of Tilapia Fillets: Kinetics and Modeling

2011 ◽  
Vol 396-398 ◽  
pp. 1306-1312 ◽  
Author(s):  
Bao Yan Zhang ◽  
Yin Zhe Jin ◽  
Yu Dong Cheng
Keyword(s):  
Experimental Data ◽  
Temperature Distribution ◽  
Mathematical Models ◽  
Output Power ◽  
Moisture Diffusivity ◽  
Microwave Drying ◽  
Effective Moisture Diffusivity ◽  
Effective Moisture ◽  
Tilapia Fillets ◽  
Kinetics Of

To study the effect of microwave output power on the drying kinetics of tilapia fillets, the drying experiments were carried out at 150W, 250W, 500W, 700W and 900W, respectively. And ten mathematical models were involved to fit experimental data. It was found that Midilli et al model gave a best fitness for this conditions applied. Besides, effective moisture diffusivity increased progressively from 1.6248×10-9(m2/s) to 10.0735×10-9(m2/s) as the power increased from 150W to 900W. In addition, to obtain more homogeneous samples, temperature distribution of tilapia fillets was analyzed when they were put in different layout forms.

Effect of Air Velocity and Temperature on the Drying Kinetics of Drumstick Leaves (Moringa Oleifera)

2012 ◽  
Vol 8 (4) ◽  
Author(s):  
Monica Premi ◽  
Harish Sharma ◽  
Ashutosh Upadhyay
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Moringa Oleifera ◽  
Moisture Diffusivity ◽  
Drying Kinetics ◽  
Drying Rate ◽  
Air Velocity ◽  
Drying Time ◽  
Effective Moisture ◽  
Kinetics Of

Abstract The present study examines the effect of air velocity on drying kinetics of the drumstick leaves in a forced convective dryer. The drumstick leaves were dried in the temperature range of 50–800 C, at different air velocity (Dv) of 0.5 and 1.3 m/s. The results indicated that drying temperature and air velocity are the factors in controlling the drying rate. Experimental data obtained for the samples for color, drying rate and drying time proved that air velocity of 1.3 m/s yielded the product superior in terms of both quality and energy efficiency as compared to the samples at 0.5 m/s. Activation energy for drumstick leaves dried with air velocity, 0.5 and 1.3 m/s was 12.50 and 32.74 kJ/mol respectively. The activation energy relates similarly with the effective moisture diffusivity which also increased with increase in air velocity and temperature.

scholarly journals Modelling the Drying Characteristics and Kinetics of Hot Air-Drying of Unblanched Whole Red Pepper and Blanched Bitter Leaf Slices

2017 ◽  
Vol 5 (1) ◽  
pp. 24
Author(s):  
Samuel Enahoro Agarry
Keyword(s):  
Moisture Diffusivity ◽  
Effective Moisture Diffusivity ◽  
Red Pepper ◽  
Coefficient Of Determination ◽  
Drying Time ◽  
Drying Characteristics ◽  
Hot Air ◽  
Effective Moisture ◽  
Drying Curves ◽  
Kinetics Of

The objective of this study was to investigate the drying characteristics and kinetics of red pepper and bitter leaf under the influence of different drying temperatures. The drying experiments were carried out at dry bulb temperature of 35, 45, 55 and 75oC, respectively in an oven dryer. The results showed that as drying temperature increased, drying rate also increased and the drying time decreased. It was observed that un-sliced red pepper and sliced bitter leaf would dry within 2.5-12 h and 1.67-7 h, respectively at temperature ranging from 75 to 35oC. The drying of red pepper and bitter leaf was both in the constant and falling rate period. Four semi-empirical mathematical drying models (Newton, Page, Henderson and Pabis, and Logarithmic models) were fitted to the experimental drying curves. The models were compared using the coefficient of determination (R^2) and the root mean square error (RMSE). The Page model has shown a better fit to the experimental drying data of red pepper and bitter leaf, respectively as relatively compared to other tested models. Moisture transport during drying was described by the application of Fick’s diffusion model and the effective moisture diffusivity was estimated. The value ranges from 15.69 to 84.79 × 10-9 m2/s and 0.294 to 1.263 × 10-9 m2/s for red pepper and bitter leaf, respectively. The Arrhenius-type relationship describes the temperature dependence of effective moisture diffusivity and was determined to be 37.11 kJ/mol and 32.86 kJ/mol for red pepper and bitter leaf, respectively. A correlation between the drying time and the heat transfer area was also developed.

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