Moisture desorption isotherms of fresh Jamun (Syzygium cumini) fruit

2017 ◽  
Vol 51 (03) ◽  
Author(s):  
S. Biswal ◽  
M. Mohapatra ◽  
M. K. Panda ◽  
S. K. Dash
Keyword(s):  
Moisture Content ◽  
Sorption Isotherms ◽  
Model Parameters ◽  
Desorption Isotherms ◽  
Predicted Values ◽  
Temperature Levels ◽  
Gab Model ◽  
Monolayer Moisture ◽  
Increasing Temperature ◽  
Moisture Desorption

<span>Moisture desorption isotherms of fresh Jamun fruit, were investigated using the methods of AOAC. Equilibrium moisture content of the samples were measured at three temperature levels viz., 5, 10 and 25 °C and nine relative humidity conditions in the range of 10-90% approximately using MSI jar. The sorption isotherms of jamun fruit followed type III (J-shaped) isotherms, characteristic of high sugar products. The reverse temperature effect occurred at water activity, aw &gt;0.75, resulting in a crossing over of the sorption curves for the adsorption isotherms only. The application of the GAB model to the experimental data, using direct nonlinear regression analysis, provided agreement between the experimental and predicted values. The GAB model parameters monolayer moisture content (Mo) and heat of sorption for monolayer (C) were found to decrease with increasing temperature.</span>

Moisture desorption isotherms of fresh Jamun (Syzygium cumini) fruit

2017 ◽  
Vol 51 (03) ◽  
Author(s):  
S. Biswal ◽  
M. Mohapatra ◽  
M. K. Panda ◽  
S. K. Dash
Keyword(s):  
Moisture Content ◽  
Sorption Isotherms ◽  
Model Parameters ◽  
Desorption Isotherms ◽  
Predicted Values ◽  
Temperature Levels ◽  
Gab Model ◽  
Monolayer Moisture ◽  
Increasing Temperature ◽  
Moisture Desorption

Moisture desorption isotherms of fresh Jamun fruit, were investigated using the methods of AOAC. Equilibrium moisture content of the samples were measured at three temperature levels viz., 5, 10 and 25 °C and nine relative humidity conditions in the range of 10-90% approximately using MSI jar. The sorption isotherms of jamun fruit followed type III (J-shaped) isotherms, characteristic of high sugar products. The reverse temperature effect occurred at water activity, aw >0.75, resulting in a crossing over of the sorption curves for the adsorption isotherms only. The application of the GAB model to the experimental data, using direct nonlinear regression analysis, provided agreement between the experimental and predicted values. The GAB model parameters monolayer moisture content (Mo) and heat of sorption for monolayer (C) were found to decrease with increasing temperature.

Moisture Sorption Characteristics of Dakuwa (Nigerian Cereal/Groundnut Snack)

2013 ◽  
Vol 9 (4) ◽  
pp. 499-504 ◽  
Author(s):  
Ocheme Boniface Ocheme ◽  
Chukwuma Charles Ariahu ◽  
Emmanuel Kongo Ingbian
Keyword(s):  
Moisture Content ◽  
Equilibrium Moisture Content ◽  
Goodness Of Fit ◽  
Sorption Isotherms ◽  
Moisture Sorption ◽  
Sorption Data ◽  
Moisture Contents ◽  
Monolayer Moisture ◽  
Increasing Temperature ◽  
Sorption Characteristics

AbstractThe moisture sorption characteristics of dakuwa at 10, 20, 30 and 400°C were studied. The experimental sorption data obtained were applied to BET, GAB, Oswin and Henderson equations to test fitness of the equations to moisture sorption of dakuwa. The sorption isotherms of dakuwa were type III isotherms (J shaped), and the equilibrium moisture content increased with increasing water activity but decreased with increasing temperature. The BET and GAB monolayer moisture contents all decreased with increasing temperature. For adsorption, the BET monolayer was higher (3.163–4.158 g/100 g solid) than that of GAB (2.931–3.728 g/100 g solid), but for desorption, the GAB monolayer (4.792–7.741 g/100 g solid) was higher than that of BET (3.962–4.480 g/100 g solid). Evaluation of goodness of fit of models revealed that moisture sorption of dakuwa was best modelled by GAB equation.

scholarly journals Water sorption kinetics of damaged beans: GAB model

2017 ◽  
Vol 21 (8) ◽  
pp. 550-555 ◽  
Author(s):  
Fernanda M. Baptestini ◽  
Paulo C. Corrêa ◽  
Jaime D. B. Vanegas ◽  
Rafael Leite ◽  
Fernando M. Botelho ◽  
...  
Keyword(s):  
Moisture Content ◽  
Water Sorption ◽  
Initial Moisture Content ◽  
Sorption Kinetics ◽  
Climatic Chamber ◽  
Gab Model ◽  
Monolayer Moisture ◽  
Increasing Temperature ◽  
And Control ◽  
Kinetics Of

ABSTRACT The objective of this study was to model the water sorption kinetics of damaged beans. Grains with initial moisture content of 53.85%, dry basis (d.b.), were used. One portion of the grains was used to obtain desorption isotherms, while the other was subjected to drying until the moisture content of 5.26% (d.b.), so that it was subjected to the adsorption. For the induction of damage, a Stein Breakage Tester was used. To obtain the equilibrium moisture content, grains were placed in a climatic chamber at 20, 30, 40 and 50 ± 1 °C combined with relative humidity of 30, 40, 50, 70 and 90 ± 3%. The GAB model fitted well to the equilibrium moisture experimental data of damaged grains and control. With increasing temperature, the monolayer moisture contents decreased in adsorption and desorption processes, ranging from 9.84 to 5.10% d.b. The lower moisture content in the monolayer in damaged grains indicates that lower moisture content is necessary to ensure their conservation.

scholarly journals Desorption Isotherms and Isosteric Heats of Fermented Cocoa Beans (Theobroma cocoa)

2015 ◽  
Vol 4 (3) ◽  
pp. 138 ◽  
Author(s):  
Djedjro C. Akmel ◽  
Kouassi E. Kakou ◽  
Kisselmina Y. Kone ◽  
Nogbou E. Assidjo ◽  
Patrice Kouame
Keyword(s):  
Moisture Content ◽  
Energy Requirement ◽  
Isosteric Heat ◽  
Cocoa Beans ◽  
Water Desorption ◽  
Average Value ◽  
Desorption Isotherms ◽  
Monolayer Moisture ◽  
Isotherm Equations ◽  
Increasing Temperature

<p>Water desorption isotherms of fermented cocoa beans from Ivory Coast were determined using the gravimetric static method of saturated salts solutions at 30 °C, 40 °C and 60 °C, and isosteric heats of desorption were calculated from Clausius-Clapeyron equation. The experimental data were fitted to several isotherm equations. The best fittings were obtained for the BET equation for aw&lt;0.50 (with an average mean relative deviation (MRD) value of 1.56%) and for the Harkins-Jura equation for aw?0.50 (with an average value MRD equation of 4.17%). The isotherms obtained at 30 °C and 40 °C are practically coincident and overlapped for aw below 0.40. Fermented cocoa beans presented a monolayer moisture content of 0.083 dry basis (d.b.) at 30 °C and this value decreases with increasing temperature. The net isostheric heats of desorption for fermented cocoa beans for the temperature range studied (30-60 °C) were estimated as a function of moisture content. The maximum net isosteric heat of desorption for fermented cocoa beans was estimated at around 13.51 kJ/mol corresponding to a moisture content value of 2.85%. The energy requirement for maintaining the moisture content low of 8.7% (d.b.) or 8% wet basis (w.b.) for safe storage of this product or for reducing the moisture content during drying was estimated at around 9.58 kJ/mol.</p>

scholarly journals Experimental Investigation of Moisture Sorption Isotherms for Mefenamic Acid Tablets

2020 ◽  
Vol 21 (4) ◽  
pp. 11-20
Author(s):  
Maha Muhyi Alhussaini ◽  
Hassanain A. Hassan ◽  
Nada S. Ahmedzeki
Keyword(s):  
Moisture Content ◽  
Water Activity ◽  
Mefenamic Acid ◽  
Sorption Isotherms ◽  
Moisture Sorption ◽  
Sorption Process ◽  
Sorption Behavior ◽  
Moisture Sorption Isotherms ◽  
Gab Model ◽  
Monolayer Moisture

   The moisture sorption isotherms of Mefenamic acid tablets were investigated by measuring the experimental equilibrium moisture content (EMC) using the static method of saturated salt solutions at three temperatures (25, 35, and 45°C) and water activity range from 0.056 to 0.8434. The results showed that EMC increased when relative humidity increased and the sorption capacity decreased, the tablets became less hygroscopic and more stable when the temperature increased at constant water activity. The sorption curves had a sigmoid shape, type II according to Brunauer’s classification. The hysteresis effect was significant along with the whole sorption process. The results were fitted to three models: Oswin, Smith, and Guggenhein - Anderson and de Boer. According to the fitting results, the GAB model was the most appropriate model to describe the sorption behavior of Mefenamic acid; it had a regression coefficient range (0.9803-0.994), %E (0.69-4.06), and low values of SEE (0.85-2.2). The monolayer moisture content was calculated using the GAB model and it was concluded that the tablets should be stored at moisture content equal or slightly higher than (0.2046, 0.1843, and 0.1437 %) for desorption and (0.2073, 0.1269, and 0.1452 %) for adsorption for the three temperatures.

scholarly journals Sorption Characteristics of Bulgarian Penny Buns (Boletus Edulis)

2020 ◽  
Vol 180 ◽  
pp. 03008
Author(s):  
Albena Durakova
Keyword(s):  
Chemical Composition ◽  
Moisture Content ◽  
Model Assessment ◽  
Physico Chemical ◽  
Bet Model ◽  
Monolayer Moisture Content ◽  
Desorption Isotherms ◽  
Monolayer Moisture ◽  
Model Linearization ◽  
Sorption Characteristics

The present study determined the sorption characteristics of Bulgarian penny buns (Boletus) for eight water activities in the 10 % 90 % range and at three temperatures, of 10 °С, 25 °С and 40 °С. The coefficients of the modified Oswin, Chung-Pfost, Halsey and Henderson models were obtained statistically. The modified Halsey model is recommended as a description of adsorption and desorption isotherms since it corresponds to the criteria for model assessment and suitability. Via BET model linearization, the values of the monolayer moisture content for water activity of aw > 0.5 and temperatures of 10 °С, 25 °С and 40 °С were established. The approximate physico-chemical composition of Bulgarian penny buns (Boletus) – moisture content – 10.80 %, protein – 32.23 %, carbohydrate 0.99 %, fat – 6.62 %, ashes – 6.20 % - was also determined.

Note: Estimation of Sorption Isotherm and the Heat of Sorption of Quinoa (Chenopodium quinoaWilld.) Seeds

2004 ◽  
Vol 10 (6) ◽  
pp. 409-413 ◽  
Author(s):  
C. Rohvein ◽  
E. Santalla ◽  
M. C. Gely
Keyword(s):  
Moisture Content ◽  
Pure Water ◽  
Absolute Temperature ◽  
Sorption Data ◽  
Statistical Adjustment ◽  
Exponential Trend ◽  
Gab Model ◽  
Sorption Heat ◽  
Monolayer Moisture ◽  
Negative Exponential

A modified Guggenheim-Anderson-de Boer (GAB) equation of four parameters was obtained to adjust the experimental sorption data for washed quinoa seeds. From the original GAB equation, only the monolayer moisture resulted in a dependence-temperature parameter showing a negative exponential trend with the absolute temperature. The results of the statistical adjustment showed that the new four parameters GAB equation adequately represented the experimental data in the range of 20 to 30°C with a corrected correlation coefficient of 0.999. The sorption heat of washed quinoa seeds was estimated by combining the GAB model with the Clapeyron equation and it resulted approximately 32% higher than the sorption heat of pure water in the temperature ranges between 20 and 60°C for temperature and 0.003 and 0.30 for moisture content. Using Othmer method the ratio of latent heats varied from 1.18 to 1.0474 in the range of moisture content studied.

scholarly journals Desorption capacity of raw energy bars with fruits of Zizyphus jujuba Mill. - Bulgaria

2021 ◽  
Vol 286 ◽  
pp. 03002
Author(s):  
Albena Durakova ◽  
Adelina Vasileva ◽  
Tzvetana Gogova ◽  
Milena Temelkova ◽  
Rumyana Krasteva
Keyword(s):  
Moisture Content ◽  
Modified Model ◽  
Type Iii ◽  
Physico Chemical ◽  
Zizyphus Jujuba ◽  
Monolayer Moisture Content ◽  
Desorption Isotherms ◽  
Monolayer Moisture ◽  
Desorption Capacity

The current study presents a mixture for raw energy bars of fresh fruits of the exotic fruit Zizyphus jujuba Mill. with origin - Bulgaria. The physico-chemical indices of the ready mixture are analyzed. A high content of carbohydrates - 24.45% and of nourishing fiber - 22.08% is reported. The desorption capacity of the exotic mixture is examined for temperatures of 10°С, 25° and 40°С in eight watery activities from 11% to 85%. The analysis shows that the equilibrium moisture lowers with the raise of temperature in constant watery activities. The desorption isotherms are of type III according to the classification of Brunauer et al. The modified model of Halsey is recommended for the isotherms description according to the estimation criteria distribution, and the model of Oswin - as a second modified model. The values of the monolayer moisture content in aw <0.5 for temperatures 10°С - 5.46% dry basis (d.b.), 25°С - 5.72% d.b. and 40°C - 4.05% d.b. are calculated Brunauer-Emett-Teller model.

scholarly journals MATHEMATICAL MODELS AND THERMODYNAMIC PROPERTIES OF MOISTURE SORPTION ISOTHERMS OF FERMENTED CASSAVA FLOUR BY RED YEAST RICE

2017 ◽  
Vol 13 (1) ◽  
pp. 29 ◽  
Author(s):  
Mutiara Nur Alfiah ◽  
Sri Hartini ◽  
Margareta Novian Cahyanti
Keyword(s):  
Thermodynamic Properties ◽  
Moisture Content ◽  
Sorption Isotherm ◽  
Moisture Sorption ◽  
Red Yeast Rice ◽  
Cassava Flour ◽  
Red Yeast ◽  
Moisture Sorption Isotherm ◽  
Gab Model ◽  
Monolayer Moisture

<p>This research aims to determine moisture sorption isotherm curves, moisture sorption isotherm models and thermodynamic properties of fermented cassava flour by red yeast rice. The moisture sorption isotherm model used are Guggenheim Anderson deBoer (GAB), Brunauer Emmet Teller (BET) and Caurie. Meanwhile, the test of modelling accuray by Mean Relative Deviation (MRD) and Root Mean Square Error (RMSE). The thermodynamic properties, i.e., enthalpy and entropy were calculated by Clausius - Clapeyron equation. The result shows that the moisture sorption isotherm curve on fermented cassava flour in a sigmoid form (type II). The GAB model is the best model for moisture sorption isotherm of fermented cassava flour by red yeast rice. The MRD and RMSE values at 30˚C, 35˚C and 40˚C are 3.12%, 2.71%, 3.81%, and 1.01, 0.35, 0.42, respectively. The monolayer moisture content at 30˚C, 35˚C and 40˚C are 6.61%, 6.27% and 6.91%, based on GAB model. Meanwhile, when the BET model was used, the monolayer moisture content are 4.92%, 4.86% and 5.19%, while by Caurie model are 6.37%, 6.18% and 5.30%, at 30˚C, 35˚C and 40˚C, respectively. The enthalpy and entropy of water sorption process were decreased when moisture content increased.</p>

scholarly journals Drying kinetics and determination of water sorption isotherms of corn

2017 ◽  
Vol 15 (2) ◽  
Author(s):  
J Roy ◽  
MA Alim ◽  
MN Islam
Keyword(s):  
Moisture Content ◽  
Sorption Isotherm ◽  
Water Sorption ◽  
Sorption Isotherms ◽  
Moisture Sorption ◽  
Drying Kinetics ◽  
Drying Time ◽  
Moisture Sorption Isotherm ◽  
Water Sorption Isotherm ◽  
Monolayer Moisture

The study was carried out for the purpose of determining the drying kinetics as well as moisture sorption isotherm of hybrid-81 corn. Corn at about 31% moisture content (wb) was dried in a forced convective hot air cabinet dryer at different drying conditions, such as variable air dry bulb temperature (40°C, 50°C and 60°C) and loading density (3.56 kg/m2, 7.12 kg/m2, and 10.68 kg/m2) as well as in shining sun at different layers (3.56 kg/m2, 7.12 kg/m2, and 10.68 kg/m2). The water sorption isotherm of the dried corn was developed using vacuum desiccators, which contained saturated salt solutions in the range of 11-93% RHs. The mono-layer moisture content calculated by the Brunauer–Emmett–Teller (BET) model (6.76 g/100 g solid) was lesser than that calculated by the Guggenheim–Anderson–De Boer (GAB) model (10.53 g/100 g solid). The energy constants were 10.45 and 4.64 as per BET and GAB equation, respectively. Both models gave suitable fits for corn. The activation energy (Ea) for diffusion of water was found to be 11.09 kcal/gm-mole for corn. Furthermore, it was noticed that, with the increase of corn layer, the drying rate decreased in case of both sun and mechanical drying. However, higher loading density resulted in efficient drying, at least up to 10.7 kg/m2. It was shown that the drying time to obtain stability was the lowest for moisture content (12.08 %) corresponding to aw of 0.65 in case of BET or GAB monolayer moisture content. This finding could be helpful in predicting the storage life of corn.J. Bangladesh Agril. Univ. 15(2): 309-317, December 2017

Sign in / Sign up

Export Citation Format

Share Document