Moisture sorption isotherms of high amylose corn starch (HACS) films at 5, 25, 35 and 45 °C within an approximate water activity (aw) range of 0.11-0.85 were obtained using a static gravimetric method. HACS films fitted a type III BET model at all temperatures studied. Water sorption process in high amylose based films was exothermic within the range of water activities investigated. There was a continuous decrease of the affinity between film sorbed structure with moisture as water content increased. Negative values of ΔG in the whole range of moisture content studied were indicative of a spontaneous process. The entropy curve exhibited a well-defined minimum corresponding at the completion of the monolayer.
Get full access to this article
View all access options for this article.
References
1.
Al-Muhtaseb A.H., McMinn W.A.M. and Magee T.R.A. (2002). Moisture sorption isotherm characteristics of food products: a review . Food and Bioproducts Processing80(C2): 118-128 .
2.
Argaiz A. and López-Malo A. (1994). Adaptación del método COST para determinación de isotermas de sorción en alimentos. Avances en Ingeniería Química.
3.
Arogba S.S. (2001). Effect of temperature on the moisture isotherm of a biscuit containing processed mango kernel flour . Journal of Food Engineering48: 121-125 .
4.
Bader H.G. and Göritz D. (1994). Investigation on high amylose corn starch films. Part 2: Water vapor sorption . Starch46(7): 249-252 .
5.
Baldwin E.A., Nisperos-Carriedo M.O. and Baker R.A. (1995). Use of edible coatings to preserve quality of lightly (and slightly) processed products . Critical Reviews in Food Science and Nutrition35(6): 509-524 .
6.
Benado A.L. and Rizvi S.S.H. (1985). Thermodynamic properties of water on rice as calculated from reversible and irreversible isotherms . Journal of Food Science50(1): 101-105 .
7.
Beristain C.I., Garcia H.S. and Azuara E. (1996). Enthalpy-entropy compensation in food vapor adsorption . Journal of Food Engineering30: 405-415 .
8.
Brunauer S., Emmet P.H. and Teller E. (1938). Adsorption of gases in multimolecular layers . Journal American Chemical Society60: 309-319 .
9.
Chinnan M.S. and Park H.J. (1995). Effect of plasticizer level and temperature on water vapor transmission of cellulose-based edible films . Journal of Food Process Engineering18: 417-429 .
10.
Cuq B., Gontard N., Aymard C. and Guilbert S. (1997). Relative humidity and temperature effects on mechanical and water vapor barrier properties of myofibrillar protein based films . Polymer Gels and Networks5: 1-15 .
11.
Debeaufort F., Voilley A. and Meares P. (1994). Water vapor permeability and diffusivity through methylcellulose edible films . Journal of Membrane Science91: 125-133 .
12.
De Leiris J.P. (1986). Water activity and permeability. In: Methlouthi M. (ed.), Food packaging and preservation-Theory and Practice. New York: Elsevier Applied Science Publishers . pp. 213-234.
13.
Donhowe I.G. and Fennema O. (1994). Edible films and coatings: characteristics, formation, definitions, and testing methods. In: Krochta JM, Baldwin EA, Nisperos-Carriedo NO (eds), Edible Coatings and Films to Improve Food Quality. Lancaster, Pa: Technomic Pub Co. pp. 1-24.
14.
Ferro Fontan C., Chirife J., Sancho E. and Iglesias H.A. (1982). Analysis of a model for water sorption phenomena in foods . Journal of Food Science47: 1590-1594 .
15.
Gabas A.L., Menegalli F.C. and Telis-Romero J. (2000). Water sorption enthalpy-entropy compensation based on isotherms of plum skin and pulp . Journal of Food Science65: 680-684 .
16.
Gennadios A. and Weller C.L. (1994). Moisture adsorption by grain protein films . Transactions of ASAE37(2): 535-539 .
17.
Gontard N., Guilbert S. and Cuq J.L. (1993). Water and glycerol as plasticizers affects mechanical and water vapor barrier properties of an edible wheat gluten films . Journal of Food Science58(1): 206-211 .
18.
Gregg S.J. and Jacobs J. (1948). An examination of the adsorption theory of Brunauer, Emmett and Teller and Brunauer, Deming, Deming and Teller . Transactions of Faraday Society44: 574-588 .
19.
Gregg S.J. and Sing K.S.W. (1967). Physical adsorption of gases by non-porous solids. In: Adsorption, Surface Area and Porosity. London: Academic Press Inc. pp. 42-45.
20.
Guilbert S. (1986). Technology and application of edible protective films. In: Mathlouthi M (ed.), Food Packaging and Preservation: Theory and Practice. New York: Elsevier Applied Science Publishers . pp. 371-394.
21.
Iglesias H.A. and Chirife J. (1982). Handbook of Food Isotherms: Water Sorption Parameters for Food and Food Components. New York: Academic Press .
22.
Kaya S., Ibanoglu S. and Kaya A. (1999). Moisture sorption characteristics of tarhana, a fermented turkish cereal food . Journal of Food Quality22: 95-100 .
23.
Kester J.J. and Fennema O.R. (1986). Edible films and coatings: a review . Food Technology40(12): 47-59 .
24.
Labuza T.P., Kaanane A. and Chen J.Y. (1985). Effect of temperature on the moisture sorption isotherms and activity shift of two dehydrated foods . Journal of Food Science50: 385-391 .
25.
Li S., Tang J. and Chinachoti P. (1996). Thermodynamics of starch-water systems: an analysis from solution-gel model on water sorption isotherms . Journal of Polymer Science34: 2579-2589 .
26.
Lievonen S.M. and Roos Y.H. (2002). Water sorption of food models for studies of glass transition and reaction kinetics . Journal of Food Science67: 1758-1766 .
27.
Madamba P.S., Driscoll R.H. and Buckle K.A. (1996). Enthalpy-entropy compensation models for sorption and browning of garlic . Journal of Food Engineering28: 109-119 .
28.
Motulsky H. (1999). Analyzing Data with GraphPad Prism. San Diego, CA, USA: GraphPad Software Inc.
29.
Mulet A., García-Reverter J., Sanjuán R. and Bon J. (1999). Sorption isosteric heat determination by thermal analysis and sorption isotherms . Journal of Food Science64(1): 64-68 .
30.
Mulet A., García-Pascual P., Sanjuán N. and García-Reverter J. (2002). Equilibrium isotherms and isosteric heat of morel (Morchella esculenta) . Journal of Food Engineering53: 75-81 .
31.
Palou E., López-Malo A. and Argaiz A. (1997). Effect of temperature on the moisture sorption isotherms of some cookies and corn snacks . Journal of Food Engineering31: 85-93 .
32.
Saravacos G.D., Tsiourvas D.A. and Tsami E. (1986). Effect of temperature on the water adsorption isotherms of sultana raisins . Journal of Food Science51(2): 381-387 .
33.
Suárez-Fernández C. and Aguerre R.J. (1997). Multilayer sorption isotherms. In: Fito P., Ortega-Rodríguez E. and Barbosa-Cánovas G.V. (eds), Food Engineering 2000. New York: Chapman & Hall . pp. 65-87.
34.
Timmermann E.O., Chirife J. and Iglesias H.A. (2001). Water sorption isotherms of foodstuffs: BET or GAB parameters? Journal of Food Engineering48: 19-31 .
35.
Velázquez G., Torres J.A. and Martin-Polo M.O. (2001). Temperature effect on the moisture sorption isotherms for methylcellulose and ethylcellulose films . Journal of Food Engineering48: 91-94 .
36.
Viollaz P.E. and Rovedo C.O. (1999). Equilibrium sorption isotherms and thermodynamic properties of starch and gluten . Journal of Food Engineering40: 287-292 .
