1. Purpose and Importance of Testing
The primary goal of testing food containers is to ensure product quality and safety, preventing harmful substances from migrating into food and safeguarding consumer health. Through scientific testing, potential defects in materials, structure, functionality, and safety can be identified. This helps manufacturers improve processes, enhance product competitiveness, and promote healthy industry development. As everyday dining tools, plastic food containers must meet national and international standards for chemical safety, physical properties, temperature resistance, sealability, and microbiological indicators to reduce food safety risks.
2. Scope of Testing
This testing applies to the following types of plastic food containers and their components:
- Household, office portable, children’s, and outdoor portable containers
- Microwave-safe, freezer-safe, compartmentalized containers, or those with sealing gaskets
- Food-contact parts, including the body, lid, and sealing gasket
- Common materials: PP, PC, PET, and starch-based biodegradable plastics
3. Core Test Items and Categories
Based on testing objectives, items are divided into four categories: material testing, structural testing, functional testing, and safety testing. Details are as follows:
3.1 Chemical Safety Indicators (Material / Safety Testing)
- Overall Migration Limit: Use 4% acetic acid, water, or oil simulants. Migration ≤ 10 mg/dm² (starch-based materials require additional trichloroethylene extractables testing).
- Heavy Metal Migration: Pb ≤ 01 mg/kg, Cd ≤ 0.002 mg/kg, Cr ≤ 0.01 mg/kg, etc.
- Plasticizer Migration: Phthalates not exceeding 0.1%.
- Primary Aromatic Amine Migration: Not detectable (detection limit 0.01 mg/kg).
- Formaldehyde Migration: ≤ 15 mg/kg.
3.2 Physical and Temperature Performance (Functional / Safety Testing)
- High Temperature Resistance: No deformation, melting, or odor after 2 hours at 120°
- Low Temperature Resistance: No breakage after 72 hours at -20°
- Thermal Shock Resistance: No breakage or deformation after rapid temperature change (e.g., -20°C → 100°C).
- Resistance to Water, Oil, and Acidic Solutions: Maintain integrity with no abnormal migration.
3.3 Physical and Usability Performance (Structural / Functional Testing)
- Sealability: No leakage under 0.5 MPa pressure or when inverted with hot water for 30 minutes.
- Impact Resistance: No breakage after a 1‑meter drop test.
- Abrasion Resistance: No damage after simulating 200 cycles of daily cleaning friction.
- Appearance: No cracks, burrs, or color differences; labeling must be clear and compliant.
3.4 Microbiological Indicators (Safety Testing)
- Total Aerobic Count ≤ 100 CFU/cm²
- coli_: Not detected
- Yeasts and Molds ≤ 10 CFU/cm²
- Testing Standards
Testing must comply with the following national and international standards:
- Chinese National Standards: GB 4806.1-2016, GB 4806.7-2023, GB 31604.8-2016
- Material Standards: GB/T 12670-2008 (PP), GB/T 11999-2008 (PE)
- International / Export Standards: FDA 21 CFR 177.1520, EU No. 10/2011, EC 1935/2004, JIS K7210
- Other Reference Standards: ISO, ASTM, and other relevant industry specifications
- Testing Methods
Different techniques are used depending on the test type:
- Chemical Analysis: Overall migration using simulant immersion; heavy metals by ICP‑MS; plasticizers by GC‑MS; primary aromatic amines and formaldehyde by HPLC.
- Physical and Temperature Testing: Use of high/low temperature chambers, boiling water immersion, and acid/oil immersion.
- Physical Performance Testing: Sealability inversion test, drop test, and abrasion tester.
- Microbiological / Sensory Testing: Plate count or membrane filtration methods per GB 4789 series; also check for off‑odors and visual defects.
- Usage and Safety Precautions
- Standard plastic food containers are not suitable for microwave or oven heating. PP materials can be used for short‑term defrosting (no more than 3 minutes).
- Allow hot food to cool before placing it in the container to prevent deformation of the sealing gasket or leakage.
- Use a soft sponge for cleaning to avoid scratching surfaces or damaging the sealing gasket.
Do not store carbonated beverages, as pressure may cause leakage or deformation.
- Conclusion
Systematic chemical, physical, microbiological, and performance testing of plastic food containers, in strict compliance with relevant standards, effectively ensures product safety and durability while reducing potential health risks to consumers. At the same time, testing helps manufacturers improve product quality, enhance market competitiveness, and promote the healthy development of the food contact materials industry.
