The use of technologies that modify food environment for preservation purposes has been extensively studied in the past two decades. Even though technological advances have been made, most of the modified atmosphere packaging (MAP) development has been empirical. In this short communication. a revision of general equations of mass transfer and criteria to design MAP systems was carried out. Mathematical relationships and models to evaluate the flux of CO2 for the packaging of non-respiring foods are discussed. Data to predict CO2 uptake for the food, such as solubility and diffusion in refrigerated MAP systems are given. (c) 2008 Elsevier Ltd. All rights reserved.