In this article, Professor Edward Kosior of Nextek and NEXTLOOPP tells us about the importance of control and verification mechanisms to safety for food-grade recycled content – and how the NEXTLOOPP project is achieving this.


Re-shaping the plastics economy to become increasingly circular is starting to gain traction. It is of course a hefty system to shift given that many hurdles to the plastics circular economy are ingrained, with recycling plastic packaging more often an after-thought than designed into the process.

We still urgently need progress in global collection infrastructure and producer responsibility for products that are placed onto the market, but at least the message to “go circular” is spreading and being adopted by major brand owners and leading virgin resin companies. I am delighted to see the latter are speedily integrating with modern mechanical and chemical recycling technologies.

The trendsetters now need to be followed by the laggards as the world shifts its focus onto urgent CO2e reductions and accelerates changes to the world’s governments and corporations’ business model. This will mean acknowledging the current status and pointing towards transformative actions and the most constructive pathways forward.

And of course hurdles keep emerging. Plastics Recyclers Europe reports that imports of recycled plastics in 2023 from outside Europe have increased at the expense of local recycling operations in response to the Packaging and Packaging Waste Regulation (PPWR). The very regulations that are meant to create a market for European recycled products.

The hidden danger in these imports is the absence of reliable control and verification mechanisms that are extremely important for food-grade recycled content.

This is where the NEXTLOOPP project is stepping in to help make the plastics industry more circular.

Finding validated local solutions for the end of life of post-consumer food-grade Polypropylene (PP) packaging has been the driving force behind NEXTLOOPP’s 53 participants, who have been actively producing and trialing a range of unique grades of high-quality food-grade recycled PP resins produced using Nextek’s PPristine™ decontamination technology.

NEXTLOOPP can now showcase 55 commercialisation trials it has run with 18 of its brand and converter participants.

Unique rPP resin grades

These commercialisation trials used five PPristine™ resin grades; Natural food-grade IM, Natural food-grade, White food-grade, Mixed Colour food-grade and non-food grade Mixed Colour INRT and the results were outstanding.

As an example, trials using 30% of NEXTLOOPP’s PPristine™ resins in both extrusion and thermoforming trays achieved product quality that is comparable with the virgin products with no changes in processing conditions.

The multi-participant project is now fine-tuning the resin quality standards that are poised to become standard for food-grade recycled PP.

In the meantime, recent trials conducted by NEXTLOOPP together with TOMRA, have resolved a major sorting quandary.

End of sorting dilemma

Up until recently, there have been a number of possible solutions to differentiate food-grade plastic packaging from the waste stream. Whilst efficient, these solutions do require changes to the packaging or labels and industry has been torn between the various options.

Without having a strong consensus either way progress has been slow.

These recent trials have flipped this dilemma on its head as they confirmed a major breakthrough in the automatic sorting of food-grade PP packaging.

The sorting trials held in February, which combined TOMRA’s near-infrared, visual spectrometry with the company’s latest deep-learning technology GAINnext™, achieved food-grade purity levels exceeding 95% in packaging applications.

This exciting development is an invaluable boost to the NEXTLOOPP project, as GAINnext™ has the potential to be rolled out to all PP packaging sorting facilities and will help produce valuable food-grade PP PCR streams.

By providing a sorted food-grade PP PCR stream, GAINnext™ will enable the NEXTLOOPP decontamination process to be carried out in many more recycling operations globally.

Foil fragments

With sorting taking a major leap forward the NEXTLOOPP team have continued stripping back packaging design to ensure every element is easily recyclable.

This brought to light the issue of aluminium foil fragments in otherwise clean rPP recyclates. As it turns out even the smallest remnants of foil on the likes of yoghurt pots disrupts the melt filtration of the recyclates by blocking the melt filters, which effectively stops the extrusion recycling process.

Aluminium die-cut lidding that is heat-sealed to PP, PS and PET containers is a common form of packaging and whilst NEXTLOOPP had already identified adhesives, inks and pigments as key challenges in packaging design, they now added foil lids to their list.

Another of NEXTLOOPP’s participants, label experts MCC Verstraete, took on the foil lid challenge and explored a number of possible solutions.

Innovative Polypropylene lids

This led them to launch an innovative polypropylene heat-sealable lidding solution that doesn’t require any heat seal lacquer and the results are outstanding. Using full mono PP packaging they achieved a 14% higher yield during the sorting phase.

This innovative PP lid, SealPPeel, optimises both sortability and recyclability. Next to the obvious sustainability improvements, there are also benefits for consumers.

Whilst aluminium seals often get damaged during transport the SealPPeel lids are twice as puncture resistant compared with thinner aluminium seals. From the consumer’s perspective, it is practical as it is easy to open and microwavable, it is also visually appealing and provides higher graphic quality to improve strong branding cues.

As Stijn Quintyn, MCC’s Business Development Manager explains, a foil-lidded container has two key challenges, one being two separate materials in one pack and the other is the remnants of foil particles on the lid once it has been torn off. This alone can result in perfectly good rPP tubs ending up in the residue stream rather than being sorted for recycling.

Final barriers

It has been close to four years since NEXTLOOPP launched with an initial mission of pulling together some 20 or so participants. Now, with over 50 participants closely collaborating they are breaking down the final barriers to producing food-grade recycled PP from post-consumer packaging into new circular economy products.

Boosting the production of recycled food-grade PP resin is a major step towards stimulating growth in the sector and creating a market where sustainable solutions will become competitive with and a replacement for virgin polymers.

Enhancing recycling capacity will be accelerated in a number of key ways, from designing packaging for simplified recycling to escalating the Plastic Packaging tax. The fact that we have proven technologies to simplify sorting, such as GAINnext™ and to decontaminate, such as PPristine™ we stand a much better chance of reaching brand owners’ targets for recycled content with locally sourced recycled plastics in food packaging.

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