Study of Drying of κ-Carrageenan Gel at Various Temperatures Using a Fluorescence Technique

Abstract

The steady-state fluorescence technique was used to study drying of κ-carrageenan gel at various temperatures. Pyranine was doped as a fluorescence probe, and scattered light, I sc , and fluorescence intensities, I, were monitored during drying of these gels. It was observed that I decreased linearly as drying time is increased. The moving boundary model based on Case II diffusion was applied to produce the packing constants, k 0, at higher temperatures. Activation energy for drying was found to be 53.9 kJ mol−1. Supporting gravimetric and volumetric measurements were also carried out during drying of gels and the corresponding activation energies were determined to be 46.4 and 58.9 kJ mol−1, respectively.