rPET raw material acceptance test

Hi everyone,

Does somebody know which kind of in house test can be done for rPET in food packaging environment? For virgin materials, I accept CoC but rPET is easier to be tampered. Could be density a good idea? 

Thanks,

Maria

The carboxylic end group (COOH) will increase for each recycling step

Usually reported as the equivalent concentration/ton of polymer

It is done on 100% virgin resin and increases 

The following resources might also help:

https://www.scielo.b...mat=pdf&lang=en

https://plasticsrecy...ations-test.pdf

https://onlinelibrar...0.1002/pts.2490

https://cpb-us-w2.wp...Thomas_Doni.pdf

https://shareok.org/....pdf;sequence=1