Drying and rehydration of oyster mushroom

Dehydration and rehydration processes of Pleurotus ostreatus fruiting bodies were investigated in this work. Mushroom samples were dehydrated at 40, 50 and 60 ºC, using drying air with relative humidity of 75 %. The rehydration was investigated at different temperatures of immersion water (25, 55 and 85 ºC) and different immersion times (30, 75 and 120 minutes). The best rehydration occurred for the samples dried at 40 ºC. The rehydration could be done in water at room temperature, during 30 minutes. Water sorption isotherms of samples were determined at 30, 40 and 50 ºC. Both GAB and BET models satisfactorily represented the experimental data of moisture sorption of dried mushrooms.

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Thermodynamic properties and moisture sorption isotherms of two pharmaceutical compounds

Proceedings of 21th International Drying Symposium ◽

10.4995/ids2018.2018.7702 ◽

2018 ◽

Cited By ~ 1

Author(s):

Amel Zammouri ◽

M. Ben Zid ◽

N. Kechaou ◽

N. Boudhrioua Mihoubi

Keyword(s):

Experimental Data ◽

Thermodynamic Properties ◽

Moisture Content ◽

Equilibrium Moisture Content ◽

Water Sorption ◽

Pharmaceutical Preparations ◽

Sorption Isotherms ◽

Integral Enthalpy ◽

Isotherm Models ◽

Water Sorption Isotherms

This investigation examines and compares the water sorption isotherms and the thermodynamic properties of two pharmaceutical preparations (Hypril and Azix) intended to be manufactured with the same process plant and equipment. The moisture equilibrium isotherms were determined at 50, 60 and 70 °C using a gravimetric technique. Five isotherm models were explored for their fitting to the experimental data. Azix showed sigmoid type II isotherms while Hypril showed type III isotherms according to the BET classification. All investigated models fitted well the water sorption isotherms of Hypril. By contrast, only GAB and Adam and Shove equations gave appropriate fit to the experimental data of Azix. For both formulations, the isosteric heat and the differential entropy decreased sharply with the increase of equilibrium moisture content to minimum values and thereafter remain constant. In the case of Azix, the integral enthalpy decreased with equilibrium moisture content while the integral entropy increased until reaching a constant value. Contrariwise, Hypril showed decreasing of the integral enthalpy and entropy with the equilibrium moisture content. Keywords: sorption isotherm, enthalpy, entropy, spreading pressure, pharmaceutical formulations

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Numerical modelling of water sorption isotherms of zeolite 13XBF based on sparse experimental data sets for heat storage applications

Energy Conversion and Management ◽

10.1016/j.enconman.2017.08.033 ◽

2017 ◽

Vol 150 ◽

pp. 392-402 ◽

Cited By ~ 5

Author(s):

Simone Semprini ◽

Christoph Lehmann ◽

Steffen Beckert ◽

Olaf Kolditz ◽

Roger Gläser ◽

...

Keyword(s):

Experimental Data ◽

Numerical Modelling ◽

Water Sorption ◽

Heat Storage ◽

Sorption Isotherms ◽

Data Sets ◽

Water Sorption Isotherms

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Moisture Sorption Isotherms of Lentil Extrudates

International Journal of Food Engineering ◽

10.1515/1556-3758.2834 ◽

2012 ◽

Vol 8 (3) ◽

Cited By ~ 1

Author(s):

Nikolay Penov ◽

Todorka Petrova ◽

Milena Ruskova ◽

Nesho Toshkov ◽

Nikolay Menkov

Keyword(s):

Experimental Data ◽

Relative Humidity ◽

Sorption Isotherms ◽

Moisture Sorption ◽

Processing Conditions ◽

Moisture Contents ◽

Moisture Sorption Isotherms ◽

The Relationship

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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Moisture Sorption Isotherms and Thermodynamic Properties of Carrot

International Journal of Food Engineering ◽

10.2202/1556-3758.1804 ◽

2011 ◽

Vol 7 (3) ◽

Cited By ~ 17

Author(s):

Valeria S. Eim ◽

Carmen Rosselló ◽

Antoni Femenia ◽

Susana Simal

Keyword(s):

Moisture Content ◽

Dry Matter ◽

Sorption Isotherms ◽

Moisture Sorption ◽

Isosteric Heat ◽

Nonlinear Regression Analysis ◽

Mean Relative Error ◽

Moisture Sorption Isotherms ◽

Different Temperatures ◽

Water Sorption Isotherms

The water sorption isotherms of carrot were determined at five different temperatures (at 10, 20, 30, 40 and 50ºC) within wide ranges of moisture content (1.3-78.4 kg water /100 kg dry matter) and water activities (0.165-0.907) by using a standardized conductivity thermohygrometer. The sorption isotherms exhibited the type III behaviour, thus, an increase in temperature promoted a decrease in water activity. The GAB, Halsey, Henderson, Iglesias & Chirife and Oswin models were tested to fit the experimental data by using nonlinear regression analysis. The GAB and Henderson models satisfactorily described the sorption isotherms (mean relative error < 5.6%). The net isosteric heat of sorption (Qstn) and the differential entropy (Sd), estimated as functions of the moisture content, decreased as the carrot moisture content increased.

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Water sorption isotherms for lemon peel at different temperatures and isosteric heats

LWT ◽

10.1016/j.lwt.2007.02.010 ◽

2008 ◽

Vol 41 (1) ◽

pp. 18-25 ◽

Cited By ~ 57

Author(s):

J.V. García-Pérez ◽

J.A. Cárcel ◽

G. Clemente ◽

A. Mulet

Keyword(s):

Water Sorption ◽

Sorption Isotherms ◽

Lemon Peel ◽

Different Temperatures ◽

Water Sorption Isotherms

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Determination of the water sorption isotherms for cassava flour

Revista Brasileira de Pesquisa em Alimentos ◽

10.14685/rebrapa.v1i2.21 ◽

2010 ◽

Vol 1 (2) ◽

pp. 83 ◽

Cited By ~ 2

Author(s):

Juliana Fermino Farias ◽

Mirele Fernandes Ferreira ◽

Wagner André dos Santos ◽

Evandro Bona

Keyword(s):

Water Sorption ◽

Chemical Properties ◽

Sorption Isotherms ◽

Small Variation ◽

Cassava Flour ◽

Different Temperatures ◽

Saline Solutions ◽

Processing Steps ◽

Water Sorption Isotherms

Cassava is a nourishing food and widely consumed in Brazil in the form of flour. However, it is necessary a more detailed study of the physical-chemical properties of the cassava flour and thus optimize its processing steps such as drying. The objective of this work was to obtain the water sorption isotherms for the cassava flour at different temperatures. For this aim, experiments were carried out using the static method with saturated saline solutions at 30, 40, 60 and 70°C. The data obtained were adjusted on available literature equations using the software MATLAB R2007b. The results indicate that the temperature ranging from 40 to 70°C does not significantly influence the cassava flour equilibrium moisture. It was also found  that both Halsey and Smith's isotherm can be used to predict the cassava flour equilibrium moisture. Furthermore, it was observed a small variation in the equilibrium moisture for water activity ranging from 0 to 0.8. DOI: http://dx.doi.org/10.14685/rebrapa.v1i2.21

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Modeling of moisture sorption isotherm and evaluation of net isosteric heat for spray-dried fortified coconut (Cocos nucifera L.) powder

British Food Journal ◽

10.1108/bfj-11-2020-1017 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Juan Carlos Lucas Aguirre ◽

German Antonio Giraldo Giraldo ◽

Misael Cortés Rodríguez

Keyword(s):

Experimental Data ◽

Moisture Content ◽

Sorption Isotherms ◽

Moisture Sorption ◽

Isosteric Heat ◽

Fundamental Parameter ◽

Sorption Data ◽

Content Type ◽

Moisture Sorption Isotherms ◽

Different Temperatures

PurposeIn order to understand interactions aw vs equilibrium moisture content (EMC) in fortified coconut powder, moisture sorption isotherms were constructed under different storage conditions in order to predict the changes in their physical, chemical and microbiological properties that occur during storage and processing, which are unique to each food.Design/methodology/approachFor which the moisture sorption isotherms were determined at three different temperatures (15, 25 and 35 °C), in a range of water activity from 0.1 to 0.90. Nine models, namely, the GAB, BET, Oswin, Smith, Halsey, Henderson, Chung and Pfost, Peleg and Caurie equations, were fitted to the sorption data. Various statistical tests were adopted as criteria to evaluate the fit performance of the models.FindingsOf the models tested, the Peleg model gave the best fit to experimental data (R2 = 0.997; RMSE = 0.276), across the full range of water activities and at different temperatures. Humidity of the monolayer (mo) was found between 2.54 and 2.34%, a fundamental parameter to define the storage and control conditions, given that it is considered the value at which the product is more stable. The net sorption isosteric heat (Qst) increased to maximum and then diminished with increased moisture content (Xw); maximum values were obtained in the Xw interval between 0.48 and 2.87% (db), being between 35.72 and 99.26 kJ/mol, where the maximum value indicates coverage of the strongest bond sites and higher adsorbate-adsorbent interaction.Originality/valueThese results provide reliable experimental data on water absorption isotherms of the CP + FAC important to determine optimal processing, storing and packaging conditions.

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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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