Food-safe and future-proof: the decontamination of r-PET

In this article, you will find out what options are available for the safe use of recycled material in food packaging and which of these is preferred by experts:  

• Integration of non-decontaminated recycled material in the barrier (ABA) structure  

• Use of 100% decontaminated material in packaging  

Recycled materials are on the rise for all everyday products: whether it’s sand toys, rain jackets, or shampoo bottles – more and more companies are trying to keep plastic in circulation for as long as possible. On the one hand, this is to protect the environment and save resources. On the other, it is to withstand the ever-increasing pressure from society and politics with regard to sustainability. In the food sector, too, there is a trend towards more packaging made from recycled materials (r-PET is currently being used predominantly), but it is precisely here that the highest safety standards are required – after all, nothing less than the health of the population is at stake. And consumer concerns are high: around 90% of German consumers are in favor of a ban on chemicals in packaging that could migrate into food – even if there is only a low health risk.¹ 

Common applications for PET include food packaging produced by thermoforming, such as open and resealable trays and containers for meat, fruit, or vegetables, as well as various cups, boxes, and blister packs. There are currently two options for using recycled material in food packaging:

The first option “encases” the non-decontaminated recycled material: in what is known as a barrier (ABA) structure, non-decontaminated recyclate (B layer) is incorporated into the middle layer between two layers of new material or decontaminated recyclate (A layer). For economic reasons, the proportion of films containing recycled material has risen continuously: the process is considered efficient, but has not yet received approval from the EU Commission as a “suitable technology.” There are concerns that the new material layer could be damaged during thermoforming in the tool or is too thin to serve as a functional barrier – a critical situation for contact with food. Approval of the technology as a “suitable technology” as defined by EU 2022/1616 is therefore still under review, but it is currently not possible to predict when a final result will be available.

In contrast, there is no risk of food contamination with the second method currently in use: with this method, the extrusion line is equipped with a decontamination unit, 100% of the material is decontaminated, extruded, and then thermoformed into the desired product. This ensures that no harmful substances from a non-decontaminated r-PET can find their way into the contents. As a result, this variant is considered to be particularly safe and able to preserve quality – which is why the process has already been classified as a “suitable technology.” Greiner Packaging also considers this variant to be a viable option for the future and has set up its infrastructure accordingly: before the r-PET flakes are extruded, they are decontaminated directly at the Greiner Packaging plant and then processed directly into film. This film is then available for thermoforming. 

To achieve food suitability, (non-decontaminated) r-PET can only be used in the middle layer (B) of ABA multilayer films; the top layer A consists of new PET material – and is therefore only suitable for resource conservation to a limited extent. “Decontamination thus has the clear advantage for us that we can use 100% r-PET in food-grade quality for our packaging,” emphasizes Florian Aschermayer, Global Senior Expert Material Excellence at Greiner Packaging. “The process is also certified by the European Food Safety Authority (EFSA) and guarantees that the entire packaging is absolutely food-safe.”

But even if the ABA structure is not the first choice for r-PET, it could be an opportunity for recycled materials that are currently not allowed to be used for food packaging: by “wrapping” it with new material, for example, r-PS could also be used for food packaging. This is not currently approved for direct food contact, but if it is incorporated into the middle layer, the packaging could still be partially made with recycled materials, thus conserving resources.