POSSIBLE INDIRECT MEASUREMENT OF DIFFUSION COEFFICIENT FROM MIGRATION KINETIC ESSAY OF FOOD PACKAGING

摘要

Diffusion coefficient is an important quantity that affects the migration process of undesirable substances, from packaging into foods, if the diffusion is the only process involved in mass transfer. The Fick's equation resolution permits to describe the kinetic of migration from polymer packaging into food or simulant, once gives the correct contour and initial conditions. Another important quantity is the partition coefficient, which quantifies the relation between the final or equilibrium concentrations in polymer and in the food/simulant. Here it is proposed a simple procedure, based on numerical resolution of the Fick's equation, where the diffusion coefficient could indirectly be measured, if the kinetic of migration had been measured and the partition coefficient is known.