Analytical investigation on the effects of industrial processes on Polyethylene Terephthalate (PET) quality

Polyethylene terephthalate (PET) is the most used packaging materials for beverages worldwide. Since plastics generate the most consistent portion of waste among materials, the use of sustainable materials is encouraged. Recycling processes have been developed and advanced, as the recovery and conversion of PET bottles into post-consumer recycled (PCR) pellets. According to the Italian law 126/2020, PET bottles could contain 100% of recycled content. Bottles are usually formed through blow molding, after melting of PET pellets. However, industrial processes may introduce new or concentrate existing hazardous chemicals, which may migrate into food and beverages. Our study aims to assess if the processes of molding, milling and then recycling bottles can affect the composition and the material properties. PET contains intentionally added substances (IAS) like additives and catalysts but also non-intentionally added substances (NIAS) that may arise from impurities and reaction by-products and by degradation of different molecules during the PET life-cycle. It is important to investigate on the possible presence of substances that can affect the quality and stability of PET and can migrate into foodstuff.