Use of a mathematical model to describe the barrier properties of edible films

A study on the influence of the solubilization and diffusion process on the barrier properties of 4 different edible films is presented. The water and oxygen barrier properties of zein, alginate, casein, and chitosan films were measured at 25 degrees C. A mathematical model was fitted to the experimental data to obtain quantitative information on both solubilization and diffusion process. Results suggest that alginate film, which shows the highest water and oxygen permeability coefficient, has both higher affinity with water and a higher macromolecular mobility than the other 3 films. The lowest water and oxygen permeability coefficient was detected for chitosan and zein films. The casein film has shown an intermediate behavior.