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Title: Journal of Food Composition and Analysis



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Title: Journal of Food Composition and Analysis


Full Journal Title: Journal of Food Composition and Analysis

ISO Abbreviated Title: J. Food Compos. Anal.

JCR Abbreviated Title: J Food Compos Anal

ISSN:


Issues/Year:

Journal Country/Territory:

Language:

Publisher:

Publisher Address:

Subject Categories:

: Impact Factor

? Saleh, M.A., Ewane, E., Jones, J. and Wilson, B.L. (2001), Chemical evaluation of commercial bottled drinking water from Egypt. Journal of Food Composition and Analysis, 14 (2), 127-152.

Abstract: Inorganic constituents and trihalomethanes were analyzed in five major brands of commercial bottled water currently used by many Egyptians and tourists visiting Egypt. The inorganic analysis included determination of both anion and cation species. Trihalomethanes analysis included the determination of chloroform, bromodichloromethane and dibromochloromethane. For the purpose of comparison. selected samples of tap water and rain water from Cairo and Giza were also analyzed. Inductively coupled plasma mass spectrometry (ICP/MS) was used for the analysis of elements including heavy metals. Ion chromatography (IC) was used for the analysis of anions. Ion selective electrodes (ISE) were used for measuring physical constants and for the analysis of nitrite, cyanide and sulphide ions, and ammonia. Gas chromatography and gas chromatography/mass spectrometry (GC;MS) were used for the analysis of trihalomethanes, All water samples were within the acceptable levels of the World Health Organization (WHO) guidelines and were lower than maximum contaminant levels (MCL) established by the United States Environmental Protection Agency (USEPA). Tap water from both Cairo and Giza was of a higher quality than any of the bottled water with regard to the analyzed chemical constituents. Out of the five brands of bottled water only Mineral(R) brand had a concentration level approaching the maximum allowed concentration for most of the chemical constituents. and it also contained the highest total dissolved solids. Trihalomethanes were found in all of the tap water but at much lower levels in Baraka(R) and Siwa(R) bottled water. Charcoal filters were effective in reducing the trihalomethanes concentration but showed no significant changes in other constituents. (C) 2001 Academic Press.

Keywords: Drinking Water, Bottled Water, Egypt, Pollutants, Ion Chromatography, ICP/MS, Cardiovascular-Disease, Lead, Absorption, Corrosion, Nitrate, Barium, Risks


Title: Journal of Food and Drug Analysis


Full Journal Title: Journal of Food and Drug Analysis

ISO Abbreviated Title: J. Food Drug anal.

JCR Abbreviated Title: J food drug anal

ISSN: 1021-9498

Issues/Year: 4

Language: Multi-language

Journal Country/Territory: Taiwan

Publisher: Natl Laboratories Foods Drugs

Publisher Address: 161-2 Kuen Yang Street, Nankang, Taipei, Taiwan

Subject Categories:

Food Science & Technology: Impact Factor 0.597, 50/95 (2003);

Pharmacology & Pharmacy: Impact Factor 0.597, 163/185 (2003)

? Lee, K.H., Wang, H.K., Itokawa, H. and Morris-Natschke, S.L. (2000), Current perspectives on Chinese medicines and dietary supplements in China, Japan and the United States. Journal of Food and Drug Analysis, 8 (4), 219-228.

Full Text: J\J Foo Dru Ana8, 219.pdf

Abstract: Chinese and other herbal medicines are being used increasingly by the general populations in both Eastern and Western countries, particularly as dietary supplements in the latter, to relieve and treat many different human diseases. By applying advanced scientific technology, herbal medicine can serve as a unique, fundamental basis for modern drug discovery and development. Herbal medicine must be researched and modernized in order to assure safety and efficacy, to provide qualitative and quantitative analyses for dietary supplements, and to develop new, effective, and safe world-class drugs. This drug design process is an iterative process of bioactivity-directed fractionation and isolation of natural lead compounds, chemical modification and improvement through structure-activity relationship, mechanism of action, drug metabolism, molecular modeling, and combinatorial chemistry studies, as well as efficacy and toxicity determination and clinical trials. From these studies, new drugs can be continuously generated from Chinese medicine. Importantly, now and in the future, not only bioactive lead compounds, but also active fractions and active prescriptions, must be investigated to continue the legacy of Chinese medicine for drug development in the 21(st) century. Such current perspectives and examples of herbal medicines and new drug development in China, Japan, the US, and other countries are illustrated in this paper.

Keywords: Chinese Medicine, Medicinal Herbs, Dietary Supplements, Drug Discovery, Drug Development, 2-Stage Carcinogenesis, Promoting Activities, Shouseiryu-TO


Title: Journal of Food Engineering


Full Journal Title: Journal of Food Engineering

ISO Abbreviated Title: J. Food Eng.

JCR Abbreviated Title: J Food Eng

ISSN: 0260-8774

Issues/Year: 16

Journal Country/Territory: England

Language: Multi-Language

Publisher: Elsevier Sci Ltd

Publisher Address: The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, Oxon, England

Subject Categories:

Engineering, Chemical: Impact Factor 1.085, 20/126 (2002)

Food Science & Technology: Impact Factor 1.085, / (2002)

McKay, G., Murphy, W.R. and Jodieri-Daddaghzadeh, S. (1987), Fluidisation and hydraulic transportation of carrot pieces. Journal of Food Engineering, 6 (5), 377-399.

Full Text: J\J Foo Eng6, 377.pdf

Abstract: The behaviour of discs and cylinders of carrot in a water-fluidised bed was studied. Pressure drop measurements and terminal (or transportation) velocity relationships were established using cylinders of carrot, PVC and Nylon 6.6. This enabled the effect of particle density to be studied. Comparisons were made with the results of previous work by McKay and McLain (1980) on spheres and cuboids.

At minimum fluidisation, large cylinders did not behave as spherical or near-spherical solids and the equation derived by Ergun (1952) for spheres, relating friction factor to Reynolds number and voidage, did not apply. However, a similar relationship has been established, viz:

which is valid for cylinders having sphericity factors in the range 0.73-0.87.

The relationships derived by Wadell (1934) for spheres and discs, having sphericities from 0.125 to 1.00 and largest dimension 5.00 mm, were unsatisfactory for predicting terminal fluidisation velocities of carrot or plastic cylinders. The resistance coefficient was related to the sphericity factor by:



logC=0·77+4· logøs

As the L/D ratio increased, i.e. the sphericity decreased, the drag on the particles was reduced. This is the converse of their settling behaviour and shows that a resistance coefficient measured in settling conditions cannot be used to predict the fluidising behaviour of cylinders having large L/D ratios.

Relationships between the slopes of the plots of log U vs log  and volumetric shape factor, K, were investigated. The slope, n, of these plots was related to K by:

log N=0.28−0.226 log K

Ahmad, M.N., Holland, C.R. and McKay, G. (1994), Mass transfer studies in batch fermentation: Mixing characteristics. Journal of Food Engineering, 23 (2), 145-158.

Full Text: J\J Foo Eng23, 145.pdf

Abstract: Studies have been undertaken to investigate the mass transfer parameters due to mixing effects during fermentation using Candida utilis in a 2.0-dm3 batch fermentor. Mechanical agitation and mixing via air flow have been studied and each varied independently of the other. Oxygen transfer rates were found to increase up to a limiting value when both airflow rate and agitation were increased. Aerobic fermentation is characterised by the specific oxygen rate which increased with agitation and airflow rate. It was found, however, that agitation and aeration had no effect on the carbon dioxide production rate but the mass transfer coefficient increased markedly with increasing agitation. Values for all the mass transfer terms were determined. The mass transfer coefficient, k(L)a, has been correlated with the impeller agitation speed, N, as follows: k(L)a = 1.079  10-3 N1.96.

Mir, M.A. and Nath, N. (1995), Sorption isotherms of fortified mango bars. Journal of Food Engineering, 25 (1), 141-150.

Full Text: J\J Foo Eng25, 141.pdf

Abstract: Sorption isotherms of plain mango bar (86.9% total sugars, 2.7% protein and 0.54% fat, db), mango-coconut bar (81.8% total sugars, 3.0% protein and 5.0% fat, db) and mango-soya protein concentrate bar (75.2% total sugars, 13.1% protein and 0.40% fat, db) were of a sigmoid shape having long second local isotherms. Their colour and texture were adversely affected during storage at RH 54.1%, and mould growth was observed after 13–43 days storage at RH 75.5%; the bars retained their quality best at RH 64.8%. The sorption data were fitted to five (BET, GAB, Henderson, Oswin and Smith) models of sorption isotherms. The BET and GAB models were found to predict well the moisture content only for the plain mango bar (R2 0.9067 and 0-9325, E % 5.59 and 10.76) whereas the Oswin model was applicable to all the three types of bars (R2 0.9201–0.9731, E % 22.65–31.44).

Minkov, S., Minchev, A. and Paev, K. (1996), Modelling of the hydrolysis and extraction of apple pectin. Journal of Food Engineering, 29 (1), 107-113.

Full Text: J\J Foo Eng29, 107.pdf

Abstract: A mathematical model, describing the extraction of pectin with a first order chemical reaction in the solid phase was proposed. A numerical solution was obtained, which is compared with the experimental data for the increase of the pectin concentration in the liquid phase. A good fit with experimental data was demonstrated. As a result the values of the rate coefficient of the acidic hydrolysis (9.8×10−4 and 9.7×10−4 s−1), the coefficient of effective diffusion in the particles (6.57×1011 and 7.9×10−11 m2/s) and the external mass transfer coefficient (6.62×10−5 m/s for particles with mean radius of 0.25×10−3 m and 2.56×10−5 m/s for particle with mean radius of 0.8125×10−3 m) were estimated.

Viollaz, P.E. and Rovedo, C.O. (1999), Equilibrium sorption isotherms and thermodynamic properties of starch and gluten. Journal of Food Engineering, 40 (4), 287-292.

Full Text: J\J Foo Eng40, 287.pdf

Abstract: A modification of the GAB isotherm (Guggenheim–Anderson–de Boer) is proposed in order to correlate the sorption data for water activities higher than 0.9. The proposed isotherm retains the desirable properties of the GAB isotherm, i.e. good fitting in the range of aw between 0.05 and 0.80, and also provides a noticeable improvement in the fitting quality for high values of aw, by introducing a new term with an additional constant. Sorption data for native potato starch and gluten at different temperatures (2°C, 20°C, 40°C and 67°C) were well correlated for the whole aw range. For starch at 67°C, the values of the constants of the proposed equation do not follow the same tendency obtained for lower temperatures, suggesting that the structure of the material could be changed due to the high temperature. The proposed isotherm can be of interest in the area of drying given that there are few isotherms that accurately represent sorption data at different temperatures in the zone of high aw. Also, it can be useful to predict other thermodynamic functions. In addition, a new procedure is proposed to determine the isosteric heat by using a second order polynomial for representing the variation of moisture as a function of temperature at a fixed water activity.

Chu, B.S., Baharin, B.S., Che Man, Y.B. and Quek, S.Y. (2004), Separation of vitamin E from palm fatty acid distillate using silica: I Equilibrium of batch adsorption. Journal of Food Engineering, 62 (1), 97-103.

Full Text: J\J Foo Eng62, 197.pdf

Abstract: In this study, vitamin E was separated from palm fatty acid distillate by batch adsorption using an orbital shaker. Silica was used as the adsorbent. Equilibrium of the adsorption process as a function of reaction temperature, agitation rate and silica mass on vitamin E adsorption onto silica was investigated over a range of vitamin E concentration. Lower reaction temperature led to higher vitamin E uptake at equilibrium, indicating that the adsorption process in this study was exothermic. Adsorption capacity increased with the rise in agitation rate. However, in this study the maximum adsorption capacity remained unchanged when silica mass was increased. Generally, non-linear regression analysis showed that the Redlich–Peterson and Langmuir isotherm models described the equilibrium data reasonably well (coefficient of determination, R2>0.90 in most cases). The Freundlich model, however, was found to be relatively poor (R2<0.90 in most cases) for explaining the adsorption equilibrium in this study. Thermodynamic parameters of the adsorption further confirmed the exothermic nature of the adsorption process as did the negative heat of enthalpy, accompanied by a negative value of entropy change. The overall Gibbs free energy change during the adsorption process was negative for the experimental range of temperatures, corresponding to spontaneous adsorption.

Keywords: Adsorption, Enthalpy, Entropy, Equilibrium, Free Energy, Isotherm, Silica, Vitamin E

Chu, B.S., Baharin, B.S., Che Man, Y.B. and Quek, S.Y. (2004), Separation of vitamin E from palm fatty acid distillate using silica: II Kinetics of batch adsorption. Journal of Food Engineering, 62 (4), 105-111.

Full Text: J\J Foo Eng62, 105.pdf

Abstract: The kinetics of vitamin E batch adsorption onto silica was detailed in this study; as functions of initial vitamin E concentration, reaction temperature, agitation rate and silica mass. For all systems, the adsorption occurred rapidly initially and then proceeded gradually to equilibrium in about 5 min. It was found that the fraction of vitamin E adsorbed onto the silica at equilibrium was higher when the initial vitamin E concentration in the solution was lower. However, the reverse was true for the effects of agitation rate and silica mass. Increasing the reaction temperature would result in lower adsorption capacity, suggesting that adsorption of vitamin E onto silica was exothermic in nature. Two main adsorption mechanisms were involved during the vitamin E adsorption, namely external mass transfer and intraparticle diffusion. The external mass transfer coefficient, kf, and rate constant of intraparticle diffusion, kid, were determined for each system. It was noted that increasing the initial vitamin E concentration resulted in a decrease in kf values, but an increase in kid values. Increase in agitation rate facilitated the adsorption processes and therefore increased both kf and kid values. Meanwhile, a higher silica mass gave a lower kid value, indicating that the intraparticle diffusion rate was lower. The activation energies were considered high (-25.45 and -54.13 kJ mol-1 for external mass transfer and intrapartiele diffusion, respectively) suggesting that the adsorption appeared to be a chemosorption rather than low energy physiosorption process.

Keywords: Adsorption, Kinetics, Silica, Vitamin E

Chu, B.S., Baharin, B.S., Che Man, Y.B. and Quek, S.Y. (2004), Separation of vitamin E from palm fatty acid distillate using silica. III. Batch desorption study. Journal of Food Engineering, 64 (1), 1-7.

Full Text: J\J Foo Eng64, 1.pdf

Abstract: Batch desorption experiments of vitamin E from silica were carried out to study the effects of reaction temperature and agitation rate on the kinetics and equilibrium of desorption. For all systems, it was found that vitamin E desorbed rapidly in the early stages, followed by a much slower release. The two distinct desorption rates might be due to the heterogeneities of the adsorbing surfaces. A first-order two-component four-parameter model described the desorption kinetics well with a coefficient of determination, R2 of >0.97. The rate constants for rapid (krap) and slow (kslow) desorption ranging from 0.51 to 2.23 min-1 and from 0.01 to 0.14 min-1, respectively, depending on reaction temperature and agitation rate. It was found that the krap value increased with increase in reaction temperature, indicating that desorption of vitamin E from silica was endothermic in nature. The desorption rate also increased with increase in agitation rate. Activation energies for the rapid and slow desorption were 38.64 and 73.08 kJ mol-1, respectively. It was found that the desorption isotherm can be fitted by the Fruendlich model. Percentage recovery of vitamin E from silica ranged from 70.36% to 98.74%, depending on the experimental variables. The results from this study provided useful information for achieving high recovery of vitamin E during its separation using an adsorption method.

Keywords: Desorption, Equilibrium, Kinetics, Silica, Vitamin E

Bera, D., Lahiri, D. and Nag, A. (2004), Kinetic studies on bleaching of edible oil using charred sawdust as a new adsorbent. Journal of Food Engineering, 65 (1), 33-36.

Full Text: J\J Foo Eng65, 33.pdf

Abstract: A new and low cost acid hydrolyzed charred sawdust as an adsorbent has been used for the purification of edible oils. The maximum colouring matter adsorbed Γpm (mg/m2) for different oils on sawdust has been calculated. The change in free energy −ΔG×10−1 (kJ/ mol) due to adsorption of colouring matter from the bulk to the interface of the sawdust has been calculated. From our result it has been found that the maximum adsorption has been comparable to the change in free energy. The thermodynamic parameters such as the activation energy, enthalpy, and entropy are presented. The negative value of ΔS indicates less disorder i.e. the crude oil contains more colourant and impurities before bleaching process and these are decreased during adsorption process because disorder is directly proportional with entropy.

Keywords: Charred Sawdust, Activation Energy, Change in Free Energy, Enthalpy and Entropy, Oil Loss

Pagano, A.M. and Mascheroni, R.H. (2005), Sorption isotherms for amaranth grains. Journal of Food Engineering, 67 (4), 441-450.

Full Text: J\J Foo Eng67, 441.pdf

Abstract: Compiling of EMC–ERH data for amaranth grains (Amaranthus cruentus L.) in the range of water activity from 0.029 to 0.979 and temperature from 25 to 90 °C was performed. Included data sets comprised experimental values of EMC–ERH that summarize 78 identified points for desorption, 53 for adsorption and 16 not discerned points that were considered for mean sorption.

Five isotherm equations for grains included in the ASAE Standards (Modified Henderson, Modified Chung–Pfost, Modified Halsey, Modified Oswin and GAB) were evaluated for their ability to fit sorption data from the literature (Me vs. aw for adsorption, desorption and mean sorption).

The goodness of fit for each isotherm was quantified through the correlation coefficient (R2), the sum of squares (RSS), the standard error of the estimate (Sy), the mean relative deviation (MRD) and the plots of residuals.

The three-parameter GAB isotherm was the best and gave a good correlation (R2 > 0.9817, RSS < 0.0293, MRD < 0.1380, Sy < 0.0141, and random residuals-plots) for the general data-fit in the range of aw from 0.1 to 0.9, of interest in seed storage and processing. The Modified Halsey equation was rejected because it gave poor statistic parameters of agreement and patterned residual plots.

For desorption, the Modified Chung–Pfost model gave the lowest mean relative deviation; the Modified Henderson equation was the second best in describing the EMC–ERH data, followed by the Modified Oswin and GAB models. For adsorption, the GAB equation presented the lesser MRD, followed by the Modified Chung–Pfost, Henderson and Oswin models. When mean sorption data were analyzed, the Modified Chung–Pfost equation was the best.

However, when the GAB isotherm was adjusted at each temperature, a higher quality of agreement was obtained compared with the other isotherms, demonstrating the adequacy of GAB model to describe the experimental data of EMC–ERH for amaranth.

Keywords: Equilibrium Moisture Content, Amaranth, Water Activity

Swami, S.B., Das, S.K. and Maiti, B. (2005), Moisture sorption isotherms of black gram nuggets (bori) at varied temperatures. Journal of Food Engineering, 67 (4), 477-482.

Full Text: J\J Foo Eng67, 477.pdf

Abstract: Adsorption–desorption behaviours of bori nuggets prepared from black gram pulse were studied at different relative humidity (ERH) ranging from 0% and 85% and temperatures at 25, 35, 45 and 55 °C following the static equilibriation technique using the saturated solutions of various salts. These data were analysed and fitted Guggenheim–Anderson–de Boer (GAB) sorption model. The temperature dependence of the respective coefficients revealed that the GAB model is acceptable (r2  0.99; MRES  0.481) in describing the EMC–ERH relationships of the nuggets. The M0, C and K values were in the range of 8.35–8.24, 82.28–41.04 and 0.74–0.72 for adsorption. The corresponding values for desorption are 9.52–8.77, 107.83–39.68 and 0.74–0.73. The net isosteric heats of sorption estimated from the Clausius–Clapeyron equation, decreased exponentially from 5.94 to 2.52 kJ mol−1 with the increase in moisture content of the sample 5–24% (db) for adsorption. The corresponding values were 8.42 to 3.42 kJ mol−1 for desorption.

Keywords: Black Gram Bori Nuggets, Sorption Isotherms, Excess Heat of Sorption

Ait Mohamed, L., Kouhila, M., Jamali, A., Lahsasni, S. and Mahrouz, M. (2005), Moisture sorption isotherms and heat of sorption of bitter orange leaves (Citrus aurantium). Journal of Food Engineering, 67 (4), 491-498.

Full Text: J\J Foo Eng67, 491.pdf

Abstract: Moisture adsorption–desorption isotherms (EMC/e.r.h.) of Citrus aurantium leaves were determined at 30, 40, and 50 °C using the standard gravimetric static method over a range of relative humidity from 0.05 to 0.9. The experimental sorption curves were fitted by six equations: modified Chung–Pfost, modified Halsey, modified Oswin, modified Henderson, modified BET, and GAB. The modified Halsey and the modified BET models were found to satisfactorily describe the desorption isotherms of Citrus aurantium leaves. For adsorption, GAB and modified BET models were the best fit. The net isosteric heats of sorption of water were determined from the equilibrium data at different temperatures.

Keywords: C. Aurantium Leaves, Equilibrium Moisture Content, Isosteric Heat of Sorption, Modelling, Sorption Isotherms

Kowalska, J. and Lenart, A. (2005), The influence of ingredients distribution on properties of agglomerated cocoa products. Journal of Food Engineering, 68 (2), 155-161.

Full Text: J\J Foo Eng68, 155.pdf

Abstract: The aim of this work was the analysis of the influence of a coating on general properties of food powders. The material used in the research consisted of such powders as: sugar, cocoa, maltodextrine and milk. For the purpose of the research mixtures of these powders were made, in the proportions of: 20% cocoa and 0–80% sugar, 0–80% maltodextrine or 0–80% milk powder, which were then agglomerated. The analysis of general properties included the change in granulometric content (mediana), loose and tapped bulk density, flowability, angle of repose and reconstitution characteristics such as wettability, isotherms and adsorption kinetics of water vapour.

Change of chemical composition of cocoa drink had an influence on the mixture’s sorption properties. Water vapour sorption capacity depended on properties of individual components. The best results were obtained for a coated mixture with composition: 20% cocoa + 80% sugar.

Keywords: Cocoa, Instant, Agglomeration, Sorption, Coating

Arslanoğlu, F.N., Kar, F. and Arslan, N. (2005), Adsorption of dark coloured compounds from peach pulp by using granular activated carbon. Journal of Food Engineering, 68 (4), 409-417.

Full Text: J\J Foo Eng68, 409.pdf

Abstract: The adsorption of dark coloured compounds from peach pulp on granular activated carbon (GAC) was studied at different GAC concentrations (0.5, 1, 3, 5 kg GAC per m3 peach pulp) and the temperature range of 20–60 °C. The equilibrium isotherm for each dark coloured compounds-GAC system was determined. Absorbance data at 420 nm were used to plot all the isotherms that are correlated reasonably well with the Langmuir, Freundlich, Temkin and Frumkin isotherms. The characteristic parameters for each isotherm were determined. The Langmuir isotherm provided the best correlation for the dark coloured compounds. Five kinetic models were evaluated to fit the experimental data: the pseudo-first-order, the pseudo-second-order, the modified Freundlich, the pore diffusion and the Elovich equations. The kinetic parameters of each model were calculated. From the experimental results obtained, the adsorption process can be well described with the Elovich model for adsorption kinetics. The calculated activation energy for process studied was 9.83 kJ/mol. This low activation energy value indicates that the adsorption process is also diffusion controlled.

Keywords: Peach Pulp, Adsorption, Discolouration, Granular Activated Carbon

? Chu, B.S., Baharin, B.S., Che Man, Y.B. and Quek, S.Y. (2005), Reply from the authors to the comments by Choong and Chuah in a recent Letter to the Editor on “Separation of vitamin E from palm fatty acid distillate using silica: 1. Equilibrium of batch adsorption by B.S. Chu et al. [Journal of Food Engineering 62 (2004) 97-103]”. Journal of Food Engineering, 69 (1), 131-132.

Full Text: J\J Foo Eng69, 131.pdf

Keywords: Kinetics

? Arslanoğlu, F.N., Kar, F. and Arslan, N. (2005), Adsorption of dark coloured compounds from peach pulp by using powdered-activated carbon. Journal of Food Engineering, 71 (2), 156-163.

Text: J\J Foo Eng71, 156.pdf

Abstract: The potential of powdered-activated carbon (PAC) for the adsorption of dark coloured compounds from peach pulp was studied at different PAC concentrations (0.5, 1, 3, 5 kg PAC per m3 peach pulp) and for the temperature range of 20–60 °C. The isotherm studies were carried out to evaluate the effect of adsorbent dosage, contact time and initial absorbance. For equilibrium adsorption curves, the Langmuir, Freundlich, Temkin and Frumkin models were attempted by using the absorbance data at 420 nm and model parameters were obtained for different temperatures. The results clearly showed that the adsorption data of dark coloured compounds present in peach pulp onto PAC fits well to the Langmuir and Temkin models having correlation coefficients higher than 0.90 at all temperatures. Five kinetic models including the first-order equation, second-order equation, the modified Freundlich, the pore diffusion model and the Elovich equation were tested to follow the adsorption processes. Results of the kinetic studies show that the adsorption reaction was well represented by the Elovich model. The activation energy of adsorption was found to be 13.79 kJ/mol. The low activation energy indicated that the adsorption reaction was also diffusion controlled.

Keywords: Peach Pulp, Powdered-Activated Carbon, Adsorption, Kinetic Models

? Mutlu, S., Cokeliler, D. and Mutlu, M. (2007), Modification of food contacting surfaces by plasma polymerization technique. Part II: Static and dynamic adsorption behavior of a model protein “bovine serum albumin” on stainless steel surface. Journal of Food Engineering, 78 (2), 494-499.

Full Text: 2007\J Foo Eng78, 494.pdf

Abstract: The static and dynamic adsorption behaviors of a model protein “Bovine Serum Albumin” on plain (SS 316) and 2-hydroxethyimethacrylate (HEMA) or polyethyleneglycolmethacrylate (PEGMA) plasma polymerization (PlzP) modified stainless steel surfaces were studied. For equilibrium adsorption behavior, Freundlich model was attempted and model parameters for Freundlich (K-F and n) were obtained. The values of the K-F and n were 24.4, 0.88; 14.9, 0.83 and 19.7, 0.85 for, SS 316, PlzP(HEMA) and PlzP(PEGMA) surfaces, respectively. The results of “static” equilibrium adsorption studies showed that, a monolayer of the protein molecules formed next to the solid surface. The dynamic adsorption process reached to the plateau value around 160 min for SS 316, 150 min for PlzP(PEGMA) and 75 min for PlzP(HEMA) surfaces. The total amount of BSA adsorbed on the SS 316, PlzP(HEMA) and PlzP(PEGMA) surfaces at the plateau were calculated as, 4.35, 2.77 and 0.38 mg, respectively: A parameter to define the dynamic behavior of the adsorption so called “Initial adsorption rate” were introduced and calculated for of BSA adsorption on the SS 316, PlzP(HEMA) and PlzP(PEGMA) surfaces as, 3310-7, 310-7 and 1010-7 9/min cm2, respectively. These dynamic results are in a very good agreement with the results obtained in static adsorption tests. (c) 2005 Elsevier Ltd. All rights reserved.

Keywords: Activated Carbon, Adsorption, Behavior, Bovine Serum Albumin, BSA, Equilibrium, Food, Freundlich Constants, Initial Adsorption Rate, Model, Modified, Parameters, Patulin Adsorption, Plasma, Plasma Polymerization, Polymerization, Protein, Protein Adsorption, Serum, Stainless Steel 316 Surface, Steel, Surface, Surfaces

? Serpen, A., Ataç, B. and Gökmen, V. (2007), Adsorption of Maillard reaction products from aqueous solutions and sugar syrups using adsorbent resin. Journal of Food Engineering, 82 (3), 342-350.

Full Text: 2007\J Foo Eng82, 342.pdf

Abstract: Adsorption of the Maillard reaction products (MRP) onto a styrene-divinylbenzene copolymer based adsorbent resin (AR) was studied. The effects of various parameters such as temperature, AR concentration, contact time, and sugar concentration were investigated. Among various isotherms, the equilibrium data fitted best to the GAB isotherm which indicated a multilayer adsorption of MRP onto AR. The temperature strongly influenced the adsorption process. The thermodynamic parameters E-a, H, G and S indicated that the adsorption process was exothermic and spontaneous process which is favored at lower temperatures, and also occurred by both physical adsorption and weak chemical interactions. Adsorption of MRP onto AR obeyed the pseudo-second-order kinetic model and occurred by both surface sorption and intraparticle diffusion. The pore diffusion controlled the adsorption process at low sugar concentrations while the film diffusion governed the adsorption mechanism at high sugar concentrations. It was concluded that the adsorption process should be performed at sugar concentrations lower than 50% to overcome the film resistance. (C) 2007 Elsevier Ltd. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Adsorbent Resin, Adsorption, Adsorption Mechanism, Adsorption Process, Aqueous Solutions, Ar, Chemical, Concentration, Concentrations, Contact Time, Copolymer, Diffusion, Effects, Equilibrium, Equilibrium Data, Exothermic, Film, Film Diffusion, Fly-Ash, GAB, Glucose Syrups, Interactions, Intraparticle Diffusion, Isotherm, Isotherms, Kinetic, Kinetic Model, Kinetics, Low, Maillard Reaction Products, Mechanism, Methylene-Blue, Model, MRP, Multilayer, Multilayer Adsorption, Parameters, Physical, Physical Adsorption, Pore Diffusion, Process, Products, Pseudo Second Order, Pseudo Second Order Kinetic, Pseudo-Second-Order, Reaction, Removal, Resin, Resistance, Solutions, Sorption, Sugar, Sugar Syrup, Surface, Temperature, Temperatures, Thermodynamic, Thermodynamic Parameters, Waste

? Soto, M.L., Moure, A., Domínguez, H. and Parajó, J.C. (2008), Charcoal adsorption of phenolic compounds present in distilled grape pomace. Journal of Food Engineering, 84 (1), 156-163.

Full Text: 2007\J Foo Eng84, 156.pdf

Abstract: Charcoal adsorption of phenolic compounds with antioxidant activity from distilled grape pomace pressing liquors (DPPL) and distilled grape pomace autohydrolysis liquors (DPAL) was carried out under anoxic conditions using commercially available activated charcoals (AC) in powdered, granulated or pelletized form. The adsorption kinetics followed a pseudo-second order rate, and equilibrium was reached in less than 15 h. The Langmuir and Freundlich model have been used to describe the equilibrium adsorption data. The maximum adsorption capacity was 239.4 mg/g AC. Fixed-bed adsorption and desorption experiments were carried out to assess the recovery and fractionation of products from exhausted AC beds and the AC susceptibility to regeneration. Recovery yields up to 20% were achieved in experiments with 96% ethanol, but neither the purity nor the antioxidant activity of the eluted fractions was affected. Five successive adsorption-desorption cycles with DPPL were performed without loss of adsorption capacity. (C) 2007 Elsevier Ltd. All rights reserved.

Keywords: AC, Activity, Adsorption, Adsorption and Desorption, Adsorption Capacity, Adsorption Kinetics, Adsorption-Desorption, Adsorption-Desorption Cycles, Anoxic, Antioxidant, Antioxidant Activity, Antioxidant Compounds, Autohydrolysis, By-Products, Capacity, Charcoal, Desorption, Equilibrium, Equilibrium Adsorption, Ethanol, Experiments, Ferulic Acid, Fixed-Bed Adsorption, Fractionation, Fractions, Freundlich, Freundlich Model, General Treatment, Granular Activated Carbon, Kinetics, Langmuir, Langmuir and Freundlich Model, Model, Order, Phenolic, Phenolic Compounds, Polymeric Adsorbents, Pressing, Pressing Liquors, Products, Pseudo Second Order, Pseudo-Second Order, Pseudo-Second-Order, Purification, Rate, Recovery, Regeneration, Salicylic-Acid, Surface-Properties, Susceptibility, White Wine Distillery Pomace

? Huang, J.Q. and Sathivel, S. (2010), Purifying salmon oil using adsorption, neutralization, and a combined neutralization and adsorption process. Journal of Food Engineering, 96 (1), 51-58.

Full Text: 2010\J Foo Eng96, 51.pdf

Abstract: The performance of activated earth and/or chitosan as an adsorbent to remove free fatty acids (FFA) and peroxides from the unpurified salmon oil was evaluated. The unpurified salmon oil was purified using three methods included activated earth adsorption process, neutralization process, and combined neutralization and activated earth adsorption processes. The purified salmon oil samples were evaluated for free fatty acids (FFA), peroxide values (PV), minerals, color, tocopherols, moisture content, insoluble impurities, and water activity. Neither chitosan nor the activated earth adsorption process was effective in removing FFA from the salmon oil. Neutralized oil had a higher intraparticular diffusion coefficient than the unpurified salmon oil for adsorbing peroxides. FFA of unpurified salmon oil was 3.5% and was significantly reduced (P < 0.05) to 0.12% by neutralization. No significant reduction of tocopherols content of the oil was observed in any of the three purification processes. After the adsorption processes, PV of neutralized oil had decreased from 4.75 to 2.90 mmol/kg. All three purification processes increased the lightness (L*) and decreased the redness (a*) and reduced mineral, insoluble impurities, moisture content, and water activity of the salmon oil. This study demonstrated that the combined process was more effective in reducing FFA, peroxides, and moisture content than either the activated earth adsorption or neutralization purification process alone. (C) 2009 Elsevier Ltd. All rights reserved.

Keywords: Activated Carbon, Adsorbent, Adsorption, Adsorption Kinetics, Catfish Oil, Chitosan, Combined Process, Diffusion, Diffusion Coefficient, Fatty-Acids, Fish Oil Purification, Intraparticular Diffusion, Lipids, Neutralization, Oxidation, Peroxide, Phospholipids, Purification Process, Reduction, Removal, Salmon Oil, Silica, Soybean Oil, Water

? Bund, R.K. and Hartel, R.W. (2010), Effect of protein on sorption characteristics of delactosed permeate. Journal of Food Engineering, 96 (3), 388-393.

Full Text: 2010\J Foo Eng96, 388.pdf

Abstract: The effects of whey protein isolate (WPI) were investigated on the characteristics of delactosed permeate (DLP) (moisture adsorption/desorption kinetics and glass transition temperature (T-g)) that reflect on the drying ability and shelf stability. The Peleg model showed a good fit to the moisture adsorption/desorption data for the DLP-protein samples. An increase in the protein concentration resulted in a decrease in the initial adsorption rate and adsorption capacity. However, its effect on extent of desorption in DLP-protein Mixtures was not significant. Tg increased with an increase in protein concentration. Significant relationships were observed between the Peleg constants for adsorption/desorption kinetics and Tg for the DLP-protein mixtures. (C) 2009 Elsevier Ltd. All rights reserved.

Keywords: Delactosed Permeate, Whey Protein Isolate, Moisture Adsorption/Desorption, Glass Transition Temperature, Glass-Transition, Water-Absorption, Moisture Sorption, Model, Soaking, Peleg

? Lu, J.L., Wu, M.Y., Yang, X.L., Dong, Z.B., Ye, J.H., Borthakur, D., Sun, Q.L. and Liang, Y.R. (2010), Decaffeination of tea extracts by using poly(acrylamide-co-ethylene glycol dimethylacrylate) as adsorbent. Journal of Food Engineering, 97 (4), 555-562.

Full Text: 2010\J Foo Eng97, 555.pdf

Abstract: Poly(acrylamide-co-ethylene glycol dimethacrylate) was synthesized by thermal polymerization. The adsorption properties of the polymers for catechins and caffeine were studied. Adsorption kinetics showed the polymers preferred to adsorb the catechins rather than caffeine, and adsorption of catechins and caffeine onto the polymers could be described by the pseudo-second-order model. Isothermal equilibrium curves of catechins and caffeine showed a good fit with Langmuir model. The maximum monolayer adsorption capacity (qm) of total catechins (192.85-171.11 mg g-1) was 3.9-5.2-folds of caffeine. Adsorption of catechins and caffeine was spontaneous and exothermic process as the change in free energy and enthalpy were negative. Lower temperature was favorable for the adsorption process. Caffeine and catechins were well separated and recovered by eluting polymers-packed column with gradient ethanol, i.e., 30% ethanol elution for separating caffeine, and 80% ethanol elution for recovering catechins. Thus, the synthetic poly(acrylamide-co-ethylene glycol dimethacrylate) could be used as a new adsorbent candidate for producing the decaffeined catechins. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.

Keywords: Adsorbent, Adsorption, Adsorption Capacity, Adsorption Kinetics, Adsorption Properties, Black Tea, Caffeine, Camellia-Sinensis, Capacity, Catechins, Catechins, Coffee, Column, Decaffeination, Elution, Energy, Enthalpy, Equilibrium, Ethanol, Exothermic, Green Tea, Health, Isothermal, Isothermal Adsorption, Kinetics, Langmuir, Langmuir Model, Lignocellulose, Model, Monolayer, Poly(Acrylamide-Co-Ethylene Glycol Dimethacrylate), Polymerization, Polymers, Pseudo Second Order, Pseudo-Second-Order, Pseudo-Second-Order Model, Rights, Temperature, Thermodynamics

? Ozsoy, H.D. and van Leeuwen, J. (2010), Removal of color from fruit candy waste by activated carbon adsorption. Journal of Food Engineering, 101 (1), 106-112.

Full Text: 2010\J Foo Eng101, 106.pdf

Abstract: The research in this paper was aimed at finding a treatment method for recovery of fruit candy (fruit leathers) wastes. Fruit leather wastes were dissolved in water to investigate the efficacy of activated carbon adsorption to remove food colorants, which reduce recycling possibilities. The effects of initial pH (2.5-9), food colorant concentration (10-110 g fruit leather/L) and adsorbent dosage (1-12 g/L) on the adsorption process were investigated. Maximum adsorption was obtained at the original pH value of dissolved fruit candy waste in water. Maximum adsorbent capacities for red, yellow and blue food colorants were 4.4: 11.7 and 2 mg/g at pH 3.5 respectively. Regeneration of food colorant loaded activated carbon can be effected at 400ºC. Cost estimates indicate that red color removal would seem to be an economical proposition, costing about $19/ton fruit candy waste, yellow marginal at $70/ton waste, and blue uneconomical at $245/ton waste. (C) 2010 Elsevier Ltd. All rights reserved.

Keywords: Activated Carbon, Activated Carbon Adsorption, Adsorbent, Adsorbent Dosage, Adsorption, Aqueous-Solutions, Carbon, Color Removal, Concentration, Dissolved, Dye Removal, Efficacy, Estimates, Food, Food Industry, Fruit Candy, Ions, NOV, pH, pH Value, Recovery, Recycle, Recycling, Regeneration, Removal, Research, Rights, Sawdust, Solid Waste, Treatment, Value, Waste, Water, Water Reclamation




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