Thermodynamic Analysis of Water Vapor Sorption Isotherms and Mechanical Properties of Selected Paper-Based Food Packaging Materials
Article first published online: 21 OCT 2009
© 2009 Institute of Food Technologists®
Journal of Food Science
Volume 74, Issue 9, pages E502–E511, November/December 2009
How to Cite
Rhim, J.-W. and Lee, J. H. (2009), Thermodynamic Analysis of Water Vapor Sorption Isotherms and Mechanical Properties of Selected Paper-Based Food Packaging Materials. Journal of Food Science, 74: E502–E511. doi: 10.1111/j.1750-3841.2009.01373.x
- Issue published online: 9 NOV 2009
- Article first published online: 21 OCT 2009
- MS 20090462 Submitted 5/25/2009, Accepted 8/28/2009.
- enthalpy/entropy compensation;
- temperature dependency;
- thermodynamic properties
ABSTRACT: Adsorption isotherms of 3 selected paper-based packaging materials, that is, vegetable parchment (VP) paper, Kraft paper, and solid-bleached-sulfate (SBS) paperboard, were determined at 3 different temperatures (25, 40, and 50 °C). The GAB isotherm model was found to fit adequately for describing experimental adsorption isotherm data for the paper samples. The monolayer moisture content of the paper samples decreased with increase in temperature, which is in the range of 0.0345 to 0.0246, 0.0301 to 0.0238, and 0.0318 to 0.0243 g water/g solid for the MG paper, the Kraft paper, and the SBS paperboard, respectively. The net isosteric heats of sorption (qst) for the paper samples decreased exponentially with increase in moisture content after reaching the maximum values of 18.51, 27.39, and 26.80 kJ/mol for the VP paper, the Kraft paper, and the SBS paperboard, respectively, at low-moisture content. The differential enthalpy and entropy of 3 paper samples showed compensation phenomenon with the isokinetic temperature of 399.7 K indicating that water vapor had been adsorbed onto the paper samples with the same mechanism. Depending on the paper material, tensile strength of paper samples was affected by moisture content.