MODELING TRANSPORT BETWEEN A MONOLAYER AND A BILAYER POLYMERIC PACKAGE AND FOOD

There is considerable interest in the recycling of food packaging, but also the potential for problems. Any chemical component initially loc ated in the re-used food packaging may be responsible for contaminatio n of the food. The kinetics of this transfer can be established whethe r the food is liquid or solid. The process is controlled by diffusion in the packaging and by convection in the liquid food or by diffusion in the solid food. A bi-layer package made of a re-used polymer layer and a virgin polymer layer exhibits quite different kinetics for the c ontamination of the food. The role of the virgin polymer layer or so-c alled functional barrier can be established either by the kinetics of contaminant transfer or by the profiles of concentration developed thr ough the packaging-food system. Dimensionless numbers are used in orde r to be of help to anyone in need of precise information on the length of time this functional barrier offers protection of the food.