Food-packaging interactions are defined as an interplay between food, packaging and the environment, which produces an effect on the food and/or package. In this part, quantitative structure–property relationships (QSPR) were developed for calculating K values based on molecular descriptors. We developed a simple method for estimating partition coefficients of 44 systems (food/migrant/packaging) of diverse physical and chemical properties such as molecular weight, polarity, HLB and LUMO energy. The molecular descriptors were derived from quantum-chemical and constitutional descriptors. The correlation coefficient (R2) was 0.96 for 41 systems and 0.94 for validation of three systems.