Meaning
Standardized testing liquids containing vegetable oil or synthetic fatty acid esters mimic the chemical interaction between plastic packaging and fatty food products. The use of simulant d2 allows laboratories to conduct migration tests that represent the worst case scenario for materials in contact with fats and oils. This liquid is chosen because it has a similar polarity to common food ingredients like butter and oil, which can draw out certain chemicals from the plastic.
The results from these tests are used to determine if the packaging meets the safety requirements set by various global regulations. The measurement stops once the material has reached a state of equilibrium with the testing liquid.
Migration Proxy
The behavior of chemicals in the plastic depends on the nature of the substance they are touching during storage. Simulant d2 acts as a proxy for all types of fatty foods, including meat and dairy products, where the migration of non-polar substances is the highest. Because it is a more aggressive solvent than water-based simulants, it is more likely to cause the transfer of additives like slip agents or plasticizers.
This makes it a critical tool for identifying the potential safety risks of a new packaging design. The choice of the simulant is based on the specific food category that the part will contain. This ensures that the safety evaluation is relevant to the actual use of the product.
Testing Protocol
The procedure involves exposing the plastic to the liquid at a specific temperature for a set amount of time. For simulant d2, the conditions are often more demanding than for other simulants due to the high stability of fats at elevated temperatures. The test can last for several days or weeks to simulate the long term shelf life of the product.
After the exposure, the liquid is analyzed to measure the amount of substances that have migrated out of the plastic. This requires a high level of precision and the use of sophisticated equipment like gas chromatography. The results must show that the migration levels are below the legal thresholds for each specific chemical.
This data provides the scientific evidence needed to support the safety declaration of the manufacturer.
Compliance Outcome
The final step in the process is to compare the test results with the limits established by the food contact regulations. Passing the tests with simulant d2 is a mandatory requirement for any packaging that will be used for fatty foods in the European market. If the part fails, the manufacturer must change the formulation of the resin or add a barrier layer to prevent the migration.
This ensures that the finished product is safe for the consumer and will not cause any health issues. The testing also helps to protect the brand from the risks of noncompliance and potential product recalls. It provides a clear and objective measure of the safety and quality of the plastic materials.
These chemical proxies allow manufacturers to prove that a specific resin grade will not contaminate fatty foods during long periods of shelf storage.
