Drying Kinetics of Onion (Allium cepa L.) Slices using Low-humidity Air-assisted Hybrid Solar Dryer

2021 ◽  
Vol 58 (03) ◽  
pp. 262-273
Author(s):  
Arun Kumar Attkan ◽  
M. S. Alam ◽  
Angam Raleng ◽  
Y. K. Yadav
Keyword(s):  
Standard Error ◽  
Goodness Of Fit ◽  
Initial Moisture Content ◽  
Moisture Diffusivity ◽  
Drying Characteristics ◽  
Coefficient Of Correlation ◽  
Solar Dryer ◽  
Thin Layer Drying ◽  
Low Humidity ◽  
Drying Conditions

Onion slices were dried in a low-humidity air-assisted hybrid solar dryer. Drying occurred in the falling rate period, and the drying rate was attenuated with the initial moisture content of the samples. The effects of different drying air temperatures (50, 60, 70°C) and KMS pre-treatments (0.1, 0.3, 0.5%) on drying characteristics of onion slices were also studied. Eight thin layer drying mathematical models viz. Newton, Page, Modified Page, Exponential, Asymptotic, Logistic, Wang and Singh, and two-term exponential were investigated and the results were compared to their goodness of fit in terms of coefficient of correlation (r), standard error (es), and the mean square of the deviation ?2. Drying characteristics of onion slices were better delineated by Page’s regression model for hybrid solar drying with values for the coefficient of correlation (0.9962–0.9999), standard error (0.0048–0.0431), and ?² (5.98E-05 to 2.16E-03). Effective moisture diffusivity values of onion slices ranged between 1.33E-08 m2.s-1 to 2.49E-08 m2.s-1 for the drying conditions under investigation.

Modeling Some Drying Characteristics of Cantaloupe Slices

2012 ◽  
Vol 45 (2) ◽  
pp. 5-14 ◽  
Author(s):  
R. Chayjan ◽  
H. Agha-Alizade ◽  
H. Barikloo ◽  
B. Soleymani
Keyword(s):  
Air Temperature ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
Initial Moisture Content ◽  
Moisture Diffusivity ◽  
Convective Drying ◽  
Drying Characteristics ◽  
Thin Layer Drying ◽  
Temperature Levels ◽  
Drying Conditions

Modeling Some Drying Characteristics of Cantaloupe Slices This study investigated thin layer drying of cantaloupe slices under different drying conditions with initial moisture content about 18.53 (d.b.). Air temperature levels of 40, 50, 60 and 70°C were applied in drying of samples. Fick's second law in diffusion was applied to compute the effective moisture diffusivity (Deff) of cantaloupe slices. Minimum and maximum values of Deff were 4.05x10-10 and 1.61x10-9 m2/s, respectively. Deff values increased as the input air temperature was increased. Activation energy values of cantaloupe slices were found between 30.43 and 36.23 kJ/mol for 40°C to 70°C, respectively. The specific energy consumption for drying cantaloupe slices was calculated at the boundary of 1.01x105 and 9.55x105 kJ/kg. Increasing in drying air temperature in different air velocities led to increase in specific energy value. Results showed that applying the temperature of 70°C is more effective for convective drying of cantaloupe slices. The aforesaid drying parameters are important to select the best operational point of a dryer and to precise design of the system.

scholarly journals Investigation of Solar Drying of Ginger (Zingiber officinale): Emprical Modelling, Drying Characteristics, and Quality Study

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
A. Waheed Deshmukh ◽  
Mahesh N. Varma ◽  
Chang Kyoo Yoo ◽  
Kailas L. Wasewar
Keyword(s):  
Energy Requirement ◽  
Initial Moisture Content ◽  
Food Preservation ◽  
Convective Drying ◽  
Drying Methods ◽  
Solar Drying ◽  
Drying Time ◽  
Drying Characteristics ◽  
Solar Dryer ◽  
Thin Layer Drying

Drying is a simultaneous heat and mass transfer energy intensive operation, widely used as a food preservation technique. In view of improper postharvest methods, energy constraint, and environmental impact of conventional drying methods, solar drying could be a practical, economical, and environmentally reliable alternative. In the present paper applicability of mixed mode solar cabinet dryer was investigated for drying of commercially important and export oriented ginger. Freshly harvested ginger slices were successfully dried from initial moisture content of 621.50 to 12.19% (d.b.) and their drying characteristics, quality parameters, and kinetics were evaluated. The results showed that present solar dryer could be successfully applied for drying of ginger in view of quality, reduced drying time, and zero energy requirement as compared to conventional open sun drying and convective drying techniques, respectively. Drying curves showed that drying occurred in falling rate period and no constant period was observed. The effective moisture diffusivity was determined by using Fick’s second law and found to be 1.789×10-9 m2/s. The drying data was fitted to five thin layer drying models and compared using statistical criteria. Page model was found to be most suitable to describe the drying kinetics of ginger in solar dryer under natural convection among the tested models.

Thin-Layer Drying Characteristics and Modeling of Paper Sludge

2012 ◽  
Vol 190-191 ◽  
pp. 575-580
Author(s):  
Han Min Xiao
Keyword(s):  
Goodness Of Fit ◽  
Effective Diffusivity ◽  
Empirical Models ◽  
Coefficient Of Determination ◽  
Paper Sludge ◽  
Mean Square ◽  
Statistical Parameters ◽  
Drying Characteristics ◽  
Thin Layer Drying ◽  
Drying Conditions

In this paper, the drying experiments of paper sludge were performed at different drying conditions. The drying kinetics and phenomena of paper sludge were investigated. The effective diffusivity and the activation energy of the paper sludge during drying had been evaluated. At the same time, seven empirical models were used to model the experimental data, such as Newton, Page, Modified Page, Henderson and Pabis, Logarithmic, Two term, Two Term exponential et al. Three statistical parameters (The coefficient of determination (R2), root mean square error (RMSE) and the residual sum of square (RSS) ) were used to evaluate goodness of fit of the tested models.

scholarly journals INFRARED DRYING OF APRICOT POMACE

2019 ◽  
Vol 49 (4) ◽  
pp. 213-218
Author(s):  
Seda Kayran ◽  
Íbrahim Doymaz
Keyword(s):  
Type Equation ◽  
Moisture Diffusivity ◽  
Coefficient Of Determination ◽  
Chi Square ◽  
Drying Characteristics ◽  
Infrared Drying ◽  
Thin Layer Drying ◽  
Apricot Pomace ◽  
Drying Conditions ◽  
Kinetics Of

Effect of infrared powers (62, 74, 88, 104 and 125 W) on drying kinetics of apricot pomace was investigated. It is observed that drying characteristics of apricot pomace were greatly influenced by infrared power. Henderson and Pabis model was investigated for describing thin-layer drying of apricot pomace. The model because of the high coefficient of determination (R2) as well as the lowest reduced chi-square (c2) and root mean square error (RMSE) values adequately described the experimental data of apple pomace drying. Effective moisture diffusivity (Deff) values were increased by increasing infrared power and changed between 1.67×10-9 and 6.03×10-9 m2/s. Activation energy was estimated by a modified Arrhenius type equation and found to be 2.32 kW/kg. The colour results were affected by drying conditions.

scholarly journals Drying characteristics and kinetics of fluidized bed dried potato

2008 ◽  
Vol 19 (2) ◽  
pp. 127 ◽  
Author(s):  
S.B. BAKAL ◽  
K.H. GEDAM ◽  
G.P. SHARMA
Keyword(s):  
Activation Energy ◽  
Developed Countries ◽  
Moisture Diffusivity ◽  
Drying Characteristics ◽  
Effective Moisture ◽  
Air Temperatures ◽  
Processed Products ◽  
Drying Conditions ◽  
Kinetics Of ◽  
Good Agreement

In developed countries, more than 50% potatoes are consumed as processed products. As drying is the vital phenomenon in processing, it is necessary to investigate the drying characteristics and its kinetics. In this experimental study, drying kinetics of Potato in two different shape of cuboidal & cylindrical with three aspect ratio was investigated as a function of drying conditions. Experiments were conducted using air temperatures of 50, 60 and 70 ºC, at velocity of 7 ms-1. The experimental moisture data were fitted to Page and simple models available in the literature, and a good agreement was observed. The Page model gave better fit than simple model. In the ranges covered, the values of the effective moisture diffusivity, Deff were obtained between 2.278 × 10-9 to 3.314 × 10-8 m2s-1 from the Fick's diffusion model. Using Deff, the value of activation energy (Ea) was determined assuming the Arrhenius-type temperature relationship.

scholarly journals Drying Modelling, Moisture Diffusivity and Sensory quality of Thin Layer dried Beef

2018 ◽  
Vol 6 (2) ◽  
pp. 552-565 ◽  
Author(s):  
Eunice Akello Mewa ◽  
Michael Wandayi Okoth ◽  
Catherine Nkirote Kunyanga ◽  
Musa Njue Rugiri
Keyword(s):  
Thin Layer ◽  
Sensory Quality ◽  
Moisture Diffusivity ◽  
Drying Kinetics ◽  
Effect Of Temperature ◽  
Slice Thickness ◽  
Drying Time ◽  
Drying Characteristics ◽  
Thin Layer Drying

The objective of the present study was to determine the drying kinetics, moisture diffusivity and sensory quality of convective air dried beef. The effect of temperature of drying (30-60°C) and thickness of samples (2.5-10 mm) on the convective thin-layer drying kinetics of beefdried in a cabinet dryer was evaluated. Five semi-theoretical models were fit to the drying experimentaldata with the aim of predicting drying characteristics of beef and fitting quality of models determined using the standard error of estimate (SEE)and coefficient of determination (R2). Determination ofeffective moisture diffusivity (Deff) from the experimental drying datawas done and sensory quality of the optimized dried cooked and uncookedbeef samplesevaluated. Drying time and rate of drying increased with an increasing temperature but decreased with increased slice thickness. However, there was overlapping of drying curves at 40-50°C. Among the selected models, Page model gave the best prediction of beef drying characteristics. Effective moisture diffusivity (Deff) ranged between 4.2337 x 10-11 and 5.5899 x 10-10 m2/s, increasing with an increase in air temperature and beef slice thickness.Of all the sensory parameters evaluated, texture was the only attribute that gave significantly different (P > 0.05) scores between the cooked and uncooked dried beef samples.

Mathematical Modelling of Thin Layer Sun and Solar Drying of Cassava Chips

2010 ◽  
Vol 6 (6) ◽  
Author(s):  
Toyosi Y Tunde-Akintunde
Keyword(s):  
Thin Layer ◽  
Correlation Coefficients ◽  
Moisture Diffusivity ◽  
Solar Drying ◽  
Drying Time ◽  
Drying Characteristics ◽  
Page Model ◽  
Thin Layer Drying ◽  
Rate Period ◽  
Pretreatment Conditions

In this paper, the effect of sun and solar drying and pretreatment conditions (soaking in water; soaking in water and then blanching; blanching and then soaking) on the drying characteristics and kinetics of cassava chips were investigated. The drying time was shorter for samples pretreated by soaking only (SK) compared to the others. It was observed that pretreatment conditions and drying method significantly (P < 0.05) affected the drying rate. The drying for all experiments occurred in the falling rate period with no constant rate period. Four mathematical models were studied for the description thin layer drying characteristics of pretreated cassava chips. The models considered were the Henderson and Pabis, Newton, Logarithmic and the Page model. Comparing the correlation coefficients (R2), chi-square (c2) and root mean square error (RMSE) values of four models, it was observed that the highest values of R2 and lowest ?2 and RMSE were obtained using Page model. This shows that the Page model represents drying characteristics better than other models. The effective moisture diffusivity values were estimated from Fick’s diffusional model. These values obtained for solar dried samples were generally higher than those obtained for sun dried samples.

Drying Kinetics of Lima Bean (Phaseolus lunatus L.) Experimental Determination and Prediction by Diffusion Models

2009 ◽  
Vol 5 (3) ◽  
Author(s):  
Wilton Pereira da Silva ◽  
Jürgen W. Precker ◽  
Antonio Gilson Barbosa de Lima
Keyword(s):  
Boundary Condition ◽  
Goodness Of Fit ◽  
Initial Moisture Content ◽  
Effective Diffusivity ◽  
Lima Bean ◽  
Diffusion Models ◽  
Phaseolus Lunatus ◽  
Convective Boundary ◽  
Thin Layer Drying ◽  
Infinite Slab

This article aims at determining thin-layer drying curves for grains of lima bean, variety olho-de-peixe and to predict them using diffusion models. Samples of lima bean (110.0 g) with initial moisture content of 66.0% (wet basis, wb) were dried at temperatures of 40.0, 50.0 and 60.0°C. The effective diffusivity of moisture was determined by analytical solutions of the mass diffusion equation (Fick’s second law) with prescribed boundary condition for spherical, cylindrical, and infinite slab at each temperature. Comparison with the experimental data showed that the infinite slab with constant diffusivity predicted more accurately, but statistical indicators of the goodness of fit were not completely satisfactory. Thus, a model for the infinite slab with constant volume, moisture-dependent diffusivity and convective boundary condition was numerically integrated. This model was solved by the numerical method of finite volumes with fully implicit formulation. The values obtained for the diffusivity were between 5.58 x 10-9 and 6.39 x 10-8 m2 min-1, being the activation energy 28.4 kJ mol-1. The model satisfactorily describes the drying process of this lima bean cultivar under all conditions investigated.

scholarly journals Modelling of vacuum drying of cherry pepper

2018 ◽  
Author(s):  
H. Boris ◽  
D. Shrilekha ◽  
J. Sujata
Keyword(s):  
Initial Moisture Content ◽  
Moisture Diffusivity ◽  
Coefficient Of Determination ◽  
Vacuum Drying ◽  
Chi Square ◽  
Plate Temperature ◽  
Moisture Movement ◽  
Drying Characteristics ◽  
Different Temperatures ◽  
Time Required

Drying is a complex phenomenon and study of drying kinetics and modelling is very important for describing the moisture movement with respect to time and predicting the dryer performance. Considering this fact, vacuum drying characteristics of cherry pepper was studied at different drying temperatures (50, 60 and 70oC). Cherry pepper were dried from initial moisture content of about 400% (dry basis) to 13 – 14.5% (dry basis) at different temperatures at 630 mm Hg vacuum. Time required to dry cherry peppers at 50, 60 and 70p C plate temperatures were 19 h, 9.75 h and 8 h respectively. Moisture reduction of cherry pepper at various temperatures was modelled using thin-layer models viz. Lewis, Page, Modified Page and Henderson and Pabis model. Based on highest value of coefficient of determination, lowest values of reduced chi square and root mean square error, Modified Page model was found to be the best fit. Moisture diffusivity increased from 6.27 × 10-10 to 1.9× 10-9m2s-1 as plate temperature increased from 50 – 70oC. Activation energy was estimated to be 50.98 kJkgmol-1.

scholarly journals Drying characteristics and mathematical modelling of the drying kinetics of oyster mushroom (Pleurotus ostreatus)

2018 ◽  
Author(s):  
A. A. Satimehin ◽  
M. O. Oluwamukomi ◽  
V. N. Enujiugha ◽  
M. Bello
Keyword(s):  
Pleurotus Ostreatus ◽  
Goodness Of Fit ◽  
Oyster Mushroom ◽  
Coefficient Of Determination ◽  
Chi Square ◽  
Drying Characteristics ◽  
Thin Layer Drying ◽  
Model Equations ◽  
Drying Behaviour ◽  
Kinetics Of

This study was conducted to determine the drying characteristics of oyster mushroom (Pleurotus ostreatus) at 50, 60 and 70 °C.  Pleurotus ostreatus were cleaned and dried in a laboratory cabinet dryer. The drying data were fitted to six model equations namely Newton, Pabis and Henderson, Logarithmic, Two-term diffusion, Wang and Singh, as well as Modified Henderson and Pabis equations. The goodness of fit of the models were evaluated by means of the coefficient of determination (R2), root mean square error (RMSE) and reduced chi-square (χ2). The Logarithmic model best describes the drying data and could be used to predict its drying behaviour. Keywords: oyster mushroom; thin-layer drying; characteristics; modelling

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