Moisture Adsorption Isotherms and Isosteric Energy for Almond

Pahlevanzadeh, H.; Yazdani, Moslem

doi:10.1111/j.1745-4530.2005.00401.x

Cited by 30 publications

(32 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…6,11,13,16 The experimental and calculated adsorption isotherms using the GAB and Oswin models are shown in Figure 2a and b, respectively. In addition, Figure 3a and b shows the modelling applied to desorption isotherms using GAB and Halsey models, respectively.…”

Section: Mathematical Modelling Of Sorption Isothermsmentioning

confidence: 99%

“…The lowest, or near zero values of SEE, RMSE and 2 , together with the highest r 2 values (near unity), and a %E less than 15% identify the best models. 4,5,7,13,16 The effect of temperature on the physicochemical parameters X m , C, k and X s of the GAB, BET and Caurie models was evaluated by an Arrheniustype equation. This method allows determination of the activation energy (E a kJ mol -1 ).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Moisture sorption isotherms and isosteric heat determination in Chilean papaya (Vasconcellea pubescens)

Vega‐Gálvez¹,

Palacios²,

Lemus‐Mondaca³

et al. 2008

Quím. Nova

View full text Add to dashboard Cite

Recebido em 17/8/07; aceito em 14/3/08; publicado na web em 26/8/08The moisture sorption isotherms of Chilean papaya were determined at 5, 20, and 45 ºC, over a relative humidity range of 10-95%. The GAB, BET, Oswin, Halsey, Henderson, Smith, Caurie and Iglesias-Chirife models were applied to the sorption experimental data. The goodness of fit of the mathematical models was statistically evaluated by means of the determination coefficient, mean relative percentage deviation, sum square error, root-mean-square error, and chi-square values. The GAB, Oswin and Halsey models were found to be the most suitable for the description of the sorption data. The sorption heats calculated using the Clausius-Clapeyron equation were 57.35 and 59.98 kJ·mol -1 , for adsorption and desorption isotherms, respectively.Keywords: Chilean papaya; sorption isotherms; isosteric heat. INTRODUCTIONThe Chilean papaya, Vasconcellea pubescens, which grows in a temperate climate regime, is a distant relative of the tropical papaya Carica papaya L.1,2 Most of the Chilean papayas come from the (irrigated) region around La Serena, Chile (ca.30 ºS) which has a Mediterranean-type climate, typically overcast mornings and evenings, and an annual relative humidity normally over 80%.3 The Chilean papaya is very different from the tropical papaya in that it is much smaller, and is consumed whole, only after cooking, with the seeds removed. It has an edible yield of 46%, a sugar content of about 5% and is high in papain content. 4 Exogenous sugar is usually added to its commercialized products, since this papaya is commercialized mainly in canned and dried (candied) forms.Water activity within a food is the amount of water available for chemical and biochemical reactions (i.e. lipid oxidation, enzymatic, and Maillard reactions), its participation in microbial development, and as a parameter useful in predicting the shelf life of the product. 5 In addition, water activity (a w ) measured within a product provides a good indicator of its shelf-life. The isotherm of a product, for a constant temperature, relates the equilibrium moisture content to the thermodynamic water activity, since in equilibrium, the latter is equal to the relative humidity of the air around the product. 6 The isotherms are important for the analysis and design of various food transformation processes such as drying, mixing, and storage; and to predict changes in food stability and aid in the selection of suitable packaging materials. 7Various empirical and semi-empirical equations have been proposed to predict the behaviour of sorption isotherms of foods and foodstuffs. The equation proposed by Guggenheim, Anderson and de Boer usually called GAB, is very useful for foods and has been recommended by the European project COST 90. 8 The GAB equation is based on the Brunauer, Emmett and Teller usually called BET adsorption theory, 9 which gives a physical explanation for the parameters of the equation. 10The monolayer moisture content (X m ) for the GAB and BET models is related to f...

show abstract

Section: Mathematical Modelling Of Sorption Isothermsmentioning

confidence: 99%

mentioning

confidence: 99%

Moisture sorption isotherms and isosteric heat determination in Chilean papaya (Vasconcellea pubescens)

Vega‐Gálvez¹,

Palacios²,

Lemus‐Mondaca³

et al. 2008

Quím. Nova

View full text Add to dashboard Cite

show abstract

“…(1985) and Midilli-Kucuk (2002) were used to fit the data. o C by Pahlevanzadeh and Yazdani [5] and Taitano and Singh [3] . They have showed GAB model as the most suitable one to predict the equilibrium moisture for almond kernel.…”

Section: Processing Of Acquired Moisture Datamentioning

confidence: 99%

“…Pearson [4] has studied the effect of temperature (55 °C to 110 °C) on drying of almonds for concealed damage. Pahlevanzadeh and Yazdani [5] have determined equilibrium moisture content of almond kernel at 15 o C, 55 o C and 75 o C. Almond dimensions, geometric mean diameter, density, porosity and other physical properties were measured by Aydin [6] , which have been used in the current study. Widely used drying kinetics of various food products have been explained through empirical and semi-empirical models e.g.…”

Section: Introductionmentioning

confidence: 99%

Drying of Almonds I: Single Particle

Chilka

Ranade

2017

Indian Chemical Engineer

View full text Add to dashboard Cite

Drying is an essential unit operation required in food processing industries, particularly in the dry fruits industry. Drying of almonds exhibit many characteristic features such as non-spherical shape, swelling/ shrinkage as a function of moisture content, uneven drying because of their peculiar shape and proximity to other almond kernels and so on. In this study, we have investigated the drying of almonds through experiments and computational modeling. In this regard, Mettler Toledo Halogen moisture analyzer unit was used to conduct experiments for a single almond kernel. In this widely used equipment, internal air flow patterns and therefore heat and mass transfer depend on natural circulation of air. A detailed three dimensional computational fluid dynamics (CFD) model was used to simulate the air flow pattern, heat and mass transfer in the drying unit. Carefully designed experiments with a single almond kernel were carried out at different temperatures to estimate key parameters of interest (drying kinetics and effective diffusivity). The CFD model was also used to quantify non-uniform heat and mass transfer and therefore non-uniform drying of a single almond kernel. The presented approach, models and results might be useful to improve the performance of drying units in industrial systems.The results and models presented here will also provide a basis for further work on multiple almond kernels and on tray dryer unit.

show abstract

“…Il s"agit en particulier de la méthode des sels saturés [6,7]. Le protocole expérimental consiste, en premier, à préparer des solutions des sels saturés.…”

Section: Ii2 Mode Opératoireunclassified

Détermination Expérimentale Et Modélisation Des Isothermes De Sorption Du Laurus Nobilis.L Du Sud Tunisie

Nasfi¹

2017

IOSR JESTFT

View full text Add to dashboard Cite

Moisture Adsorption Isotherms and Isosteric Energy for Almond

Cited by 30 publications

References 14 publications

Moisture sorption isotherms and isosteric heat determination in Chilean papaya (Vasconcellea pubescens)

Moisture sorption isotherms and isosteric heat determination in Chilean papaya (Vasconcellea pubescens)

Drying of Almonds I: Single Particle

Détermination Expérimentale Et Modélisation Des Isothermes De Sorption Du Laurus Nobilis.L Du Sud Tunisie

Contact Info

Product

Resources

About