Packaging processes of food powders and drugs often take place under a protective atmosphere in order to reduce the oxygen concentration of the surrounding gas phase during the dosing procedure, thus guaranteeing a longer shelf life of the products. A novel numerical simulation method based on a Lagrange model using OpenFOAM((R)) was developed to evaluate new dosing systems in advance for their safety regarding the residual oxygen level in the product. The results of experimental setups are used for validation.