About Food Contact Testing of Polyethylene Terephthalate (PET) Polymers

Polyethylene terephthalate materials (and their copolymers) are used in a wide variety of food contact materials from storage containers to flexible packaging.The FDA requires that polyethylene terephthalate resins intended for use in food contact applications must meet certain requirements for identity and extractable content. 

Approach

1.       Samples must be identified by NMR analysis.

2.       Extractable content is measured in distilled water for 2 hours.  

3.       Extractable content is measured in n-heptane for 2 hours.  

4.       Extractable content is measured in ethyl alcohol (with water) for 2 to 24 hours.  

5.       The necessary extractions may vary depending on the application of the material. 

Sample Considerations

50 square inches per extraction will be needed to complete the testing. NMR analysis will require 30 mg of sample.