Pollutant Transfer into Food from Sandwich Packaging with Layers of Different Thicknesses Made of Recycled and Virgin Polymers

Abstract

The process of pollutant transfer into food from sandwich packaging of different thicknesses has been studied. The thicknesses of the virgin layers or functional barriers were different, the one in contact with the food being much thicker than the other in contact with the surrounding. A numerical model based on finite differences was built, by considering the following facts: the transient diffusion through the three layers of the packaging with the same and constant diffusivity, the convection at the packaging-food interface with a coefficient of mass transfer, the volumes of food and packaging. Dimensionless numbers were used in order to obtain general results of use in various typical cases. The kinetics of the pollutant transfer into the food, the profiles of concentration of pollutant developed through the packaging, and the concentration-time histories of the pollutant on the surface of the packaging, were calculated for different values of the parameters.