Chinese National Food Contact Plastic Declaration File Inspection Workflow
Chinese food contact plastic declaration files require accredited GB standard migration reports, complete additive SML tracking, and strict lot traceability.
Polypropylene Migration Testing
Meaning
Standardized analytical procedure measures the transfer of low molecular weight additives and oligomers from polypropylene packaging into food simulants under controlled time and temperature conditions. Governed by regulations such as EU 10/2011 and FDA 21 CFR 177.1520, polypropylene migration testing quantifies overall migration limit and specific migration limits for antioxidants, slip agents, plasticizers and light stabilizers. Test protocols employ food simulants such as ethanol solutions or vegetable oil to simulate contact with different food categories.
Evaluation applies strictly to finished plastic materials intended for direct food contact.
Simulant Selection
Chemical nature of the intended food dictates which liquid simulants are exposed to polymer samples. Performing polypropylene migration testing involves immersing test specimens in aqueous or fatty food simulants at temperatures matching actual use conditions. High-temperature applications require exposure to olive oil or synthetic fatty simulants at elevated test temperatures.
Volatile additives migrate rapidly into organic solvents, yielding precise concentration data via gas chromatography.
Oligomer Quantification
Low molecular weight polypropylene oligomers represent a portion of total extractable substances in polyolefin packaging. During polypropylene migration testing, liquid chromatography coupled with mass spectrometry isolates cyclic and linear oligomer fractions. Excessive oligomer extraction indicates inadequate polymerization control or degraded polymer matrix.
High oligomer levels cause off-flavor in sensitive food products and fail regulatory migration limits.
Compliance Certification
Passing migration thresholds yields analytical certificates required for commercial food packaging sales. Polypropylene migration testing establishes legal compliance before resin grades receive authorization for food contact applications.