HomeIndustry InsightsRecycled PET Trays Release More Cyclic Oligomers Than Virgin PET

Recycled PET Trays Release More Cyclic Oligomers Than Virgin PET


In a recent study published in "Food Packaging and Shelf Life," researchers at Aarhus University in Denmark discovered that cyclic oligomer migration is greater in recycled polyethylene terephthalate (PET) trays than in virgin PET trays. The study, led by Gianluca Colombo, compared PET trays with varying ratios of recycled content and produced via two different extrusion processes.


The team analyzed seven PET trays made from 0, 73, 90, and 100% recycled PET using MALDI time-of-flight mass spectrometry (MALDI-TOF-MS) to assess molecular weight distribution. They also conducted migration tests according to European regulations using food simulant D1 at 40 °C for 10 days. Results showed a decrease in molecular weight distribution in recycled PET trays compared to virgin PET trays, indicating depolymerization due to mechanical recycling. Targeted and untargeted analyses using UHPLC-QTOF-MS revealed varying levels of cyclic PET oligomers migrating into the food simulant among the different trays.


This research highlights the importance of monitoring the migration of cyclic oligomers from recycled PET trays and underscores potential risks associated with the use of recycled materials in food packaging. 

Previous article
Next article