From coffee side stream to paper bags: Finnish circular economy innovation takes the next step

In August 2026, TAMK, Natural Indigo Finland, BioInk, Meira, Siegwerk and Hornung Verpackungen successfully printed paper bags using a water-based ink formulated with colorants derived from coffee-production side streams

The project shows how industrial side streams can become high-value materials while reducing packaging printing’s dependence on fossil-based and synthetic pigments.

From laboratory research to industrial printing

The project began two years ago with research into bio-based colorants from industrial side streams. In 2025, coffee-derived colorants were successfully used for flexographic printing on fibre-based shopping bags, demonstrating their performance in an industrial environment.

The innovation gained international recognition. Coffee-ink packaging won the public vote in the New Wood 2025 competition and the Sustainable Innovations Competition at PacTec in Helsinki. It has also received several international nominations for its innovative use of circular economy principles and sustainable material development.

TAMK’s Biocolores research group and its industry partners have since improved the ink’s color strength and technical performance, enabling more demanding packaging applications.

Creating value from coffee side streams

The colorants are derived from coffee-industry side streams supplied by Meira Oy. Using Natural Indigo Finland’s BioInk technology, Siegwerk formulated them into industrial water-based printing inks.

Materials previously directed to energy recovery can thus become high-value renewable resources. Progress from laboratory research to national pilot production and an international industrial demonstration creates a pathway towards wider use of renewable colorants in packaging.

“We are proud to see our coffee-production side stream become part of a more sustainable packaging value chain. This project shows how collaboration can transform industrial by-products into valuable resources and new circular economy solutions,” says Heidi Päiväniemi, Marketing & Sustainability Director at Meira Oy.

“This collaboration combines side-stream valorization, research and industrial printing technology to produce renewable colorants for demanding applications. It is an important step towards commercial adoption,” says Pasi Ainasoja, CEO of Natural Indigo Finland and BioInk Ltd.

Paper bags provide the next industrial benchmark

The cross-bottom bag print run marked an important step towards commercialization. Conducted with Siegwerk’s expertise in sustainable printing technologies, the trial achieved excellent print quality, process compatibility and performance under production conditions.

The ink generates no VOC emissions and uses Siegwerk’s high bio-renewable content technical varnish as a binder.

“This coffee colorant fits perfectly with our bio-renewable portfolio. Sustainable ink development has often focused on renewable binders. Coffee-derived colorants help complete the picture. The trial demonstrated technical and commercial feasibility for further industrial scaling," says Paul Pain, Global Head of Waterbased Technology at Siegwerk.

Building the future of circular packaging

For TAMK, the project demonstrates how applied research can create industrial impact and support the circular economy. Its innovation ecosystem includes packaging manufacturers willing to test sustainable solutions in real production environments.

We have researched the upcycling of industrial side streams into valuable colorants for years. This innovation has significant potential in flexographic printing and beyond. It also shows our students how higher education and industry can create sustainable innovations with real-world impact.

Kai Lankinen, Dr. Principal Researcher and Head of TAMK's Biocolores research group 

“Sustainability is increasingly important across the packaging sector. This project allowed us to evaluate an innovative bio-based ink under real production conditions,” says Rüdiger Hornung, Managing Director of Hornung Verpackungen.

The successful trial is another milestone on the journey from laboratory research to industrial adoption. Today, coffee side streams are helping print paper bags. Tomorrow, similar bio-based colorants may be used in packaging worldwide.

About the Partners

Tampere University of Applied Sciences (TAMK) www.tuni.fi/tamk
A leading Finnish university of applied sciences known for strong industry collaboration and applied research in sustainable materials and technologies. Biocolores is one of TAMK’s key research groups. Contact Kai Lankinen, kai.lankinen [at] tuni.fi (kai[dot]lankinen[at]tuni[dot]fi), tel. +358504277616

Siegwerk GmbH www.siegwerk.com
One of the world’s leading ink suppliers committed to sustainability. Contact Paul Pain, paul.pain [at] siegwerk.com (paul[dot]pain[at]siegwerk[dot]com), tel. +447854183990

Hornung Verpackungen www.hornung-verpackungen.de
A leading German supplier of high-quality bakery packaging. Contact Rüdiger Hornung.

BioInk / Natural Indigo Finland – www.naturalindigo.fi 
Develops plant- and bio-based industrial colorants from renewable materials and organic side streams. Contact Pasi Ainasoja, info [at] naturalindigo.fi (info[at]naturalindigo[dot]fi), tel. +358400282370

Meira Oy www.meira.fi/en
A major Finnish coffee roaster and spice producer with science-based climate targets. Part of Massimo Zanetti Beverage Group, Meira works to reduce waste and environmental impacts. Contact Heidi Päiväniemi, heidi.paivaniemi [at] meira.fi (heidi[dot]paivaniemi[at]meira[dot]fi), tel. +358407437850