Paperboard Food Contact Declarations and Recycled Fiber Traceability
Food contact safety for recycled board requires functional barrier proof and complete chain of custody documentation down to invoice line items.
Migration Test Limits
Chemical Threshold
Permitted concentrations of chemical substances that may transfer from packaging materials into food products define the safety margins of packaging materials. These criteria, established as migration test limits, restrict the quantity of specific substances such as plasticizers or monomers that can be released. Compliance is determined by exposing the packaging material to food simulants under specified temperature and duration.
Analytical Evaluation
Quantification of the migrating compounds involves both overall migration limits and specific migration limits. While overall migration limits restrict the total amount of non-volatile substances that can transfer, specific migration limits apply to individual hazardous compounds. Liquid chromatography or gas chromatography is used to measure these trace concentrations.
Ensuring that these values remain below the legal thresholds is necessary to secure regulatory approval for the packaging in food contact applications.
Laboratory Procedure
Simulation of actual use conditions requires matching the test temperature and time to the intended storage shelf-life. Since migration rates increase at elevated temperatures, the testing protocols use accelerated conditions to simulate long-term room temperature storage or short-term hot-fill situations. Standardized food simulants like ethanol solutions or synthetic oils are used to mimic the behavior of fatty and aqueous foods.
Failing to meet these migration test limits requires reformulating the paperboard coating or selecting higher-purity raw materials.