Silver nanoparticles (Ag NPs) are increasingly used in the food industry because of their excellent antibacterial activity. They are integrated into coatings of various food packaging to help ensure longer product shelf life. Nonetheless, the risks associated with Ag NPs are currently not well known and their potential effects on humans are causing growing concern. Furthermore, it is not clear whether NPs have greater or lesser risk than dissolved silver ions or bulk phase Ag. Consequently, it is necessary to characterize the release of silver from silver-enhanced containers into food matrices using sensitive analytical techniques that allow one to distinguish between silver ions and nanoparticles. Single particle ICP-MS is a promising technique to quantify and determine size distributions of very small particles at low concentrations and distinguish between ionic and particulate forms of the analyte. This study focused first on the aging of Ag NPs in three different food simulants (Milli-Q water, 10% ethanol and 3% acetic acid) and in two beverages (orange juice and infant milk formula) in order to validate the technique for low NP concentrations. Acidic media caused significant NP oxidation while the organic macromolecules in the juice appeared to increase the stability of the NPs. Subsequently, a migration study from silver-enhanced containers showed that release was mainly due to ionic forms of the silver. Significant release of dissolved Ag occurred in 3% acetic acid (58% of the total Ag mass of the containers) with lower release being observed in Milli-Q water (33%), 10% ethanol (29%), orange juice (17%) and milk formula (5%). Heating led to a considerable release of silver (again dissolved), likely because of the swelling of the polymer containers. The study suggests that the risks to foods associated with Ag NP in packaging can be determined using existing regulations and guidelines based on (ionic) Ag.