Mondelēz International, PepsiCo and pladis are taking part in a Belgium-wide trial, the first at national scale in Europe to involve flexible post-consumer packaging, testing whether digital watermarks can produce sorting data accurate enough for food-grade recycling.
The project is part of the HolyGrail 2030 - Circular Packaging Consortium, facilitated by AIM - European Brands Association, bringing together around 80 companies and organisations working on intelligent sorting and new technologies for recycling. Digimarc watermarks - imperceptible codes printed across the full surface of packaging during manufacture - are read by high-resolution cameras at sorting facilities.
The codes carry both material type and whether the pack was used for food, which is something current sorting technology cannot provide. Near-infrared sorting, the current standard in materials recovery facilities, can identify polymer type but not whether a piece of flexible packaging previously held food. Food-grade mechanical recycling needs feedstock sorted by both material type and prior use, and without a way to make that separation at the sorting stage, recyclate from post-consumer film cannot reach food-contact applications.
Belgium began including flexible plastic packaging in its household kerbside recycling collection between 2019 and 2021, so the project has a national-scale stream of post-consumer film to draw on. Sorted bales of film will be sent to Hündgen Entsorgung's sorting centre in Swisttal, Germany, where cameras supplied by machine manufacturer Pellenc ST read the watermarks.
Previous HolyGrail 2.0 trials on rigid packaging at the same facility achieved detection rates above 99 per cent and daily throughput of almost 56,000 items. Flexible packaging is frequently damaged and contaminated during collection, which makes detection harder. The trial which is to be managed by Fost Plus, the organisation responsible for household packaging recycling in Belgium, will test how the technology performs under conditions that have not yet been tested at national scale with real post-consumer material.
The EU's Packaging and Packaging Waste Regulation (PPWR) will from 2030 require certain categories of contact-sensitive plastic packaging to contain at least 10 per cent post-consumer recycled content. CEFLEX, the collaborative initiative of more than 180 European companies working on flexible packaging circularity, has estimated that meeting the regulation's targets will require 2.5 million tonnes of post-consumer flexible packaging recyclate - an amount that depends on sorting infrastructure that does not yet exist at the necessary scale.
"Food-contact recycled content is where the industry has some of the biggest challenges and the least time," said Liz Morrish, Operations Director on the CEFLEX Leadership Team. "This trial moves testing from evidence-gathering into commercial reality, which is exactly what bridging the gap between ambition and the 2030 targets requires."
Constantia Flexibles, which converts the printed films used in the trial, integrates the watermark directly into the packaging design during the printing process. Applied across a large area of the pack surface, the code can remain detectable even when packaging is damaged. "The design and printing process is more than decoration," said Dietmar Lenko, VP Consumer Innovation and Product Sustainability at Constantia Flexibles. "It can become an enabler of circularity."
