Advances in Food Science and Engineering

Download PDF (272.5 KB) PP. 18 - 27 Pub. Date: March 29, 2017

DOI: 10.22606/afse.2017.11003

• Ramón Moreira^*
  Department of Chemical Engineering, Universidade de Santiago de Compostela, Lope Gómez de Marzoa St, Santiago de Compostela, E-15782, Spain
• Francisco Chenlo
  Department of Chemical Engineering, Universidade de Santiago de Compostela, Lope Gómez de Marzoa St, Santiago de Compostela, E-15782, Spain
• María D. Torres
  Department of Chemical Engineering, Universidade de Santiago de Compostela, Lope Gómez de Marzoa St, Santiago de Compostela, E-15782, Spain
• Diego M. Prieto
  Department of Chemical Engineering, Universidade de Santiago de Compostela, Lope Gómez de Marzoa St, Santiago de Compostela, E-15782, Spain

Experimental water desorption isotherms of glucose, fructose and sucrose were determined at different temperatures (20, 35, 50, and 65ºC) using a static gravimetric method. Saturated salt solutions were selected to obtain different water activities from 0.09 to 0.91. All tested isotherms were type III following Brunauer’s classification. The experimental data were satisfactory fitted by Henderson and Iglesias and Chirife models. A complete statistical analysis was performed, determining that Henderson model was more suitable to fit the desorption isotherms of tested sugars, since it satisfied all the rejection criteria and showed, in all studied cases, the highest values of lumped measure for the goodness of fit. Predicted water desorption isotherms of sucrose from the experimental sorption isotherms of its individual monomers (glucose and fructose), in moles of water per mol oxygen, nicely matched with those obtained experimentally.

Equilibrium moisture content, henderson model, iglesias and chirife model, temperature, water activity

[1] Levy DE, Fügedi P, The Organic Chemistry of Sugars. Boca Raton, USA: Taylor & Francis Group, 2006.

[2] Imeson A, Food stabilisers, thickeners and gelling agents. London, UK: Wiley-Blackwell, 2010.

[3] Sivasankar B, Food Processing and Preservation. New Delhi, India, 2002.

[4] Al-Muhtaseb A, McMinn W, Magee T., “Water sorption isotherms of starch powders. Part 2: thermodynamic characteristics,” Journal of Food Engineering, vol. 62, pp. 135-142, 2004.

[5] Koloor RT, Jayas DS, White NDG, “Adsorption and desorption characteristics of buckwheat,” International Journal of Agricultural Biology, vol. 8, pp. 327-329, 2006.

[6] Brunauer S, Deming LS, Deming WE, Teller E, “On a theory of the Van der Waals adsorption of gases,” Journal of Ameican Chemistry Society, vol. 62, pp. 1723–1732, 1940.

[7] Bell LN, Labuza TP, Moisture Sorption: Practical Aspects of Isotherm Measurement and Use. St. Paul, USA: American Association of Cereal Chemists, 2000.

[8] Moreira R, Chenlo F, Torres MD, Silva C, Prieto DM, Sousa AMM, Hillou L, Gon?alves MP, “Drying kinetics of biofilms obtained from chestnut starch and carrageenan with and without glycerol,” Drying Technology, vol. 29, pp. 1058-1065, 2011.

[9] Herman E, De la Cruz J, García MA, “Prediction of pineapple sorption isotherms using the Ross equation”Drying of Technology, vol. 17, pp. 915-923, 1999.

[10] Moreira R, Chenlo F, Torres MD, “Simplified algorithm for the prediction of water sorption isotherms of fruits, vegetables and legumes based upon chemical composition,” Journal of Food Engineering, vol. 94, pp. 334-343, 2009a.

[11] Ditmar JH, “Hygroscopicity of sugars and sugar mixtures,” Journal of Industrial Engineering Chemistry, vol. 27,pp. 333, 1935.

[12] Makower B, Dye WB, “Sugar crystallization, equilibrium moisture content and crystallization of amorphous sucrose and glucose,” Journal of Agriculture Food Chemistry, vol. 4, 72-77, 1956.

[13] Penner EA, Schmidt SJ, “Comparison between moisture sorption isotherms obtained using the new vapor sorption analyser and those obtained using the standard saturated salt slurry method,” Journal of Food Measurement Characteristics, vol. 7, pp. 185-193, 2013.

[14] Moreira R, Chenlo F, Torres MD, Prieto DM, “Desorption isotherms and net isosteric heat of chestnut flour and starch,” Food and Bioproducts Technology, vol. 4, pp. 1497-1504, 2009b.

[15] Greenspan L, “Humidity fixed points of binary saturated aqueous solutions,” Journal of Research Natural Bureau Standarda Section A. vol. 81, pp. 89-102, 1977.

[16] Labuza TP, Knnane A, Chen JY, “Effect of temperature on the moisture sorption isotherm and water activity shift of two dehydrated foods,” Journal of Food Science, vol. 50, pp. 385–392, 1985.

[17] AOAC. Official methods of analysis. Washington, USA: Association of Official Analytical Chemistry, 2000.

[18] Iglesias HA, Chirife J, “An empirical equation for fitting isotherms of fruits and related products,” Journal of Institute Canada Science Technology, vol. 11, pp. 12-15, 1987.

[19] Henderson SM, “A basic concept of equilibrium moisture,” Agricultural Engineering, vol. 33, pp. 29–32, 1952.

[20] Mrad ND, Bonazzi C, Boudhrioua N, Kechaou N, Courtois F, “Influence of sugar composition on water sorption isotherms and on glass transition in apricots” Journal of Food Engineering, vol. 111, pp. 403-411, 2012.

[21] Ruiz-López II, Herman-Lara E, “Statistical indices for the selection of food sorption isotherm models,” Drying Technology, vol. 27, pp. 726-738, 2009.

[22] Farahnaky A, Mansoorib N, Majzoobia M, Badii F, “Physicochemical and sorption isotherm properties of date syrup powder: Antiplasticizing effect of maltodextrin,” Food and Bioproducts Procesing, vol. 98, pp. 133–141, 2016.

[23] Fasina OO, “Thermodynamic properties of sweet potato” Journal of Food Engineering, vol. 75, pp. 149–155, 2006.

[24] Vega-Gálvez A, López J, Ah-Hen K, Torres MJ, Lemus-Mondaca R, “Thermodynamic properties, sorption isotherms and glass transition temperature of cape Gooseberry (Physalis peruviana L.),” Food Technology and Biotechnology, vol. 52, pp. 83-92, 2014.

[25] Staudt PB, Tessaro IC, Marczak LDF, Soares RP, Cardozo NSM, “A new method for predicting sorption isotherms at different temperatures: Extension to the GAB model,” Journal of Food Engineering, vol. 118, pp.247–255, 2013.

[26] Polachini TC, Betiol LFL, Lopes-Filho JF, Telis-Romero J, “Water adsorption isotherms and thermodynamic properties of cassava bagasse” Thermochimica Acta, vol. 632, pp. 79–85, 2016.

[27] Brown A, Understanding Food. Principles & Preparation. Merseyside, UK: Wadsworth Publishing Company, 2007.