Moisture Sorption Isotherms, Drying Behavior, and Quality Attributes of Mango Sheets Dried Using Hot Air Combined with Relative Humidity Control

Abstract The equilibrium moisture contents (EMC) were determined for lentil extrudates produced under different processing conditions at 25°C and eight relative humidity (RH) in the range of 0.113 – 0.902. It was established that for the ten extruded samples the EMC values at the same RH were not statistically equal. Four models – Chung-Pfost, Halsey, Oswin, and Henderson equations were applied for analyzing the experimental data. The Oswin model was most suitable for describing the relationship between the EMC and RH.

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Experimental Determination of Moisture Sorption Isotherm of Fecal Sludge

Water ◽

10.3390/w11020303 ◽

2019 ◽

Vol 11 (2) ◽

pp. 303 ◽

Cited By ~ 3

Author(s):

Catherine Bourgault ◽

Paul Lessard ◽

Claire Remington ◽

Caetano C. Dorea

Keyword(s):

Relative Humidity ◽

Water Distribution ◽

Gravimetric Method ◽

Sorption Isotherms ◽

Moisture Sorption ◽

Critical Data ◽

Moisture Sorption Isotherm ◽

Fecal Sludge ◽

Moisture Sorption Isotherms ◽

Gab Model

Dewatering and drying of fecal sludge (FS) is a key treatment objective in fecal sludge management as it reduces volume (thereby reducing emptying frequency and associated transportation costs), inactivates pathogens, and is beneficial and/or necessary to resource recovery activities such as composting and combustion as fuel. However, studies on dewatering performances of FS are limited. The physical water distribution of such matrices is not fully understood, limiting the progress in the development and optimization of FS dewatering technologies. The objective of this study is to present a gravimetric method intended to assess the dewatering characteristics and associated modelling of FS through moisture sorption isotherms. Samples were placed in airtight jars containing different saturated salt (NaOH, CaCl2, NaCl, KCl, K2SO4) solutions to reproduce a range of relative humidity values (6 to 97%). Results confirmed the achievement of characteristic sigma-shaped moisture sorption isotherms with increasing moisture adsorption at higher values of relative humidity. Furthermore, experimental data best fit the three-parameter Guggenheim–Anderson–de Boer (GAB) model. This method can be replicated to contribute critical data about the characterization of fecal sludge, a seriously under-researched matrix.

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Modeling of the Equilibrium Moisture Content (EMC) of Tarragon (Artemisia Dracunculus L.)

International Journal of Food Engineering ◽

10.2202/1556-3758.1025 ◽

2005 ◽

Vol 1 (5) ◽

Cited By ~ 10

Author(s):

Akbar Arabhosseini ◽

Willem Huisman ◽

Anton van Boxtel ◽

Joachim Müller

Keyword(s):

Relative Humidity ◽

Moisture Content ◽

Equilibrium Moisture Content ◽

Sorption Isotherms ◽

Moisture Sorption ◽

Relative Deviation ◽

Artemisia Dracunculus ◽

Significant Difference ◽

Moisture Sorption Isotherms ◽

The Relationship

The equilibrium moisture content of tarragon, Artemisia dracunculus L. (stem and leaf separately) was determined by using the saturated salt solutions method at three temperatures (25, 50 and 70°C) within a range of 5 to 90% relative humidity. Both adsorption and desorption methods were used for stem and leaf of two varieties: Russian and French tarragon. Experimental curves of moisture sorption isotherms were fitted by modified Henderson, modified Halsey, modified Oswin, modified Chung-Pfost and GAB equations and evaluated by residual sum squares, standard error of estimate and mean relative deviation. The modified Halsey and GAB equations were found to be the most suitable for describing the relationship among equilibrium moisture content, relative humidity and temperature. There was no significant difference between the equilibrium moisture content of the Russian and French tarragon.

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Determination of Moisture Sorption Isotherm of Crosslinked Millet Flour and Oxirane Using GAB and BET

Journal of Chemistry ◽

10.1155/2018/2369762 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

M. S. Alamri ◽

A. A. Mohamed ◽

S. Hussain ◽

M. A. Ibraheem ◽

Akram A. Abdo Qasem

Keyword(s):

Relative Humidity ◽

Moisture Content ◽

Sorption Isotherm ◽

Sorption Isotherms ◽

Moisture Sorption ◽

Water Binding ◽

Moisture Sorption Isotherm ◽

Water Sorption Isotherm ◽

Moisture Sorption Isotherms ◽

Different Temperatures

Epoxy resin was prepared by crosslinking epoxidized oil and millet flour. The reaction was carried out at three different temperatures (25, 40, and 55°C) and zinc chloride levels (1, 2, and 3%). Moisture sorption isotherms were determined at 0.1 to 0.9 water activity (aw) using a gravimetric sorption analyzer (Q 2000). The sigmoidal shape (type II) of the resin isotherms exhibited lower equilibrium moisture content (EMC) at higher temperature. The experimental data were modeled using GAB (Guggenheim–Anderson–de Boer) and BET (Brunauer–Emmett–Teller). The EMC of the resin was significantly lower than that of the flour, which could be attributed to the decrease in the number of water-binding sites due to the creation of dense areas during crosslinking. The low root-mean-square error (RMSE) indicates that GAB and BET were suitable for predicting the water sorption isotherm for millet flour resin. The heat of sorption of the resin was large at low moisture content and increased at higher relative humidity. It is recommended that millet flour resin be used at relative humidity below 60%.

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Moisture sorption isotherms of millet seeds

Czech Journal of Food Sciences ◽

10.17221/8316-cjfs ◽

2000 ◽

Vol 18 (No. 3) ◽

pp. 86-90 ◽

Cited By ~ 1

Author(s):

N.D. Menkov ◽

D.I. Gelyazkov

Keyword(s):

Experimental Data ◽

Relative Humidity ◽

Moisture Content ◽

Equilibrium Moisture Content ◽

Sorption Isotherms ◽

Moisture Sorption ◽

Static Method ◽

Moisture Contents ◽

Moisture Sorption Isotherms ◽

The Relationship

The equilibrium moisture contents were determined for millet seeds of two cultivars using the gravimetric static method at 10, 25 and 40°C over a range of relative humidities from 0.112 to 0.868. The sorption capacity of the seeds decreased with an increase in temperature at constant relative humidity. The hysteresis effect is not distinctly expressed but statistically significant. The differences between equilibrium moisture contents of the cultivars are small. Four models were applied for analyzing the experimental data using the following equations: modified Chung-Pfost, modified Halsey, modified Oswin, and modified Henderson. The modified Chung-Pfost model was found to be the most suitable for describing the relationship between equilibrium moisture content, relative humidity and temperature.

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