A coffee roaster’s by-product has made an unusual journey.

Instead of going directly to energy recovery, part of that material has been processed into a colourant, formulated into a water-based printing ink and run on an industrial paper-bag printing line in Germany.

In August 2026, Tampere University of Applied Sciences, Natural Indigo Finland, BioInk, Meira, Siegwerk and Hornung Verpackungen completed an industrial trial using a coffee-derived colourant to print paper bags.

TAMK says the run achieved the print quality, process compatibility and performance needed to support further industrial scaling.

That is a meaningful step.

But it is important not to turn it into something the project has not yet proved.

There is no announced commercial launch.

There is no disclosed annual production capacity for the coffee-derived colourant.

There is no published ink price.

There is no reported press speed, run length, ink consumption, colour-variation data or comparison with a conventional pigment system.

And there is no independent life-cycle assessment demonstrating how much environmental impact the new formulation actually avoids.

So the story is not:

“Coffee waste has replaced conventional packaging ink.”

The more accurate story is:

a bio-based colourant that began as a laboratory project has now survived another important industrial qualification step—and the remaining barriers are becoming commercial rather than conceptual.

The Important Breakthrough Happened on the Press

Many bio-based material projects perform well in a laboratory.

Far fewer reach an operating packaging plant.

That transition matters because printing ink is not judged simply by whether it can produce colour on a sample sheet.

A flexographic ink has to behave predictably while the press is running.

Its viscosity has to remain manageable.

Its colour strength has to be sufficient.

It has to transfer through the anilox system.

It must release correctly from the printing plate.

It has to wet the substrate.

It needs to dry within the available press configuration.

And the printed result must remain consistent as production continues.

A formulation that produces an attractive laboratory sample can still fail once speed, drying, process control and repeatability enter the equation.

That is why Hornung Verpackungen’s involvement is important.

The German manufacturer already produces paper bags using water-based printing inks. Its published product information for both cross-bottom and gusseted paper bags lists water-based printing as part of its normal manufacturing capability.

The coffee-derived ink therefore did not have to prove that water-based flexographic printing itself works on paper bags.

That process is already established.

It had to prove something more commercially relevant:

can this new colourant be formulated so that it behaves inside a production environment that already expects conventional industrial ink performance?

That is a much better measure of its potential.

This Project Has Already Passed Several Different Gates

The development did not jump directly from coffee waste to Hornung’s production line.

TAMK says research began around 2024 with work on extracting bio-based colourants from industrial side streams.

In May 2025, Natural Indigo Finland and TAMK reported the first industrial proof of concept. Coffee-derived colourant supplied from Meira’s roasting side streams was formulated into a water-based ink and used by Cabassi to flexographically print fiber-based bag material.

That package later won the public vote in Finland’s Uusi Puu 2025 competition. Natural Indigo Finland says the project received 15% of a record 1,800 public votes.

In March 2026, the ink also won the Sustainable Innovations Competition held alongside PacTec, FoodTec and PlastExpo Nordic in Helsinki. At that stage, TAMK said the formulation used a coffee-derived bio-colourant and Siegwerk’s renewable-raw-material-based binder system.

Then came the August 2026 trial with Hornung.

That sequence matters:

laboratory extraction → proof of concept → formulation improvement → industrial packaging trial.

For anyone working in packaging development, this progression is more informative than the awards.

Each stage removes a different kind of uncertainty.

The current trial suggests the question is gradually shifting away from:

“Can this be printed?”

toward:

“Can this be manufactured and supplied reliably enough to become a real ink raw material?”

The Colourant Is the More Interesting Part of the Ink

There is another technical distinction worth making.

Much of the packaging industry’s work on lower-fossil-content inks has concentrated on the vehicle, binder and solvent system.

That makes sense.

Solvent choice and resin chemistry have major implications for drying, emissions, adhesion and environmental performance.

Siegwerk itself is developing lower-fossil-content raw-material routes elsewhere in its portfolio. In June, for example, it announced work with Celanese using ethyl acetate containing 50% bio-based content in existing ink formulations.

The Finnish coffee project attacks another part of the formulation:

the colour-producing component.

According to TAMK, Siegwerk formulated the coffee-derived material into an industrial water-based ink using BioInk technology, while a technical varnish containing a high proportion of bio-renewable raw materials serves as the binder.

That is significant because an ink is not simply pigment plus water.

A commercial formulation can include colourants, binders, additives and other components needed to control printing behaviour and end-use properties.

Replacing one fossil- or synthetically derived component therefore does not automatically make the whole formulation 100% bio-based.

The partners themselves describe the colourant as bio-based and the binder as having a high bio-renewable content.

They do not publish a complete formulation or an overall renewable-content percentage for the finished ink.

So I would avoid describing this as a completely fossil-free printing ink.

The more defensible description is:

a water-based packaging ink using a colourant derived from coffee-roasting side streams and a binder with high bio-renewable content.

That wording preserves what has actually been demonstrated.

“Water-Based” and “VOC-Free” Should Not Be Treated as the Same Claim

TAMK also says the formulation used in the project generates no VOC emissions.

That is a formulation-specific claim and should be reported as such.

It should not be generalized into:

“water-based inks do not contain VOCs.”

They can.

U.S. EPA technical material notes that water-based inks can contain organic co-solvents and that VOC content varies considerably between formulations.

Water-based flexographic inks generally provide a route to much lower VOC emissions than traditional solvent-heavy systems, especially in paper and paperboard printing, but the actual emissions profile depends on the formulation.

So there are really two separate developments here.

The project uses a water-based ink platform, which is already familiar to paper-bag printing.

And the partners say this particular formulation has no VOC emissions during use.

The second claim comes from the project participants and has not been independently verified in the published material.

That distinction keeps the sustainability argument technically credible.

Coffee Waste Is Not Automatically a Low-Carbon Pigment

The circular-economy story is appealing.

Meira’s coffee-industry side stream had previously been directed toward energy recovery. The project instead extracts value from the material before that final energy pathway.

Conceptually, that is attractive.

A material that previously produced value mainly through energy recovery could now become a raw material for another manufacturing process.

But the environmental conclusion cannot stop there.

To determine whether the coffee-derived colourant has a lower overall footprint than the pigment it replaces, the industry would eventually need to understand:

how the colourant is extracted;

what chemicals are required;

how much water and energy the process consumes;

the extraction yield;

how the material is dried or concentrated;

transport requirements;

waste generated during processing;

and the conventional pigment against which it is being compared.

None of those figures has been published in sufficient detail.

Therefore, the project demonstrates side-stream valorisation.

It does not yet quantify a full life-cycle environmental advantage over conventional ink colourants.

Those are not the same claim.

Colour Strength May Be the First Serious Commercial Test

TAMK specifically says its Biocolores team and industrial partners have been working to improve colour strength and technical performance.

That detail deserves more attention.

Colour strength affects much more than appearance.

If a bio-based colourant needs substantially more material to achieve the same optical result as a conventional pigment, several other parts of the economics can change.

More colourant could mean:

higher ink consumption;

greater formulation cost;

different viscosity behaviour;

different drying requirements;

or limits on how intense a shade can practically be produced.

We do not know whether any of those issues apply to this particular coffee colourant.

No comparative formulation data have been published.

But the fact that colour strength remains an explicit development area tells us where part of the technical work is concentrated.

This also suggests that the first commercially attractive applications may not necessarily be those demanding the strongest or widest colour gamut.

Natural brown and earth-tone graphics, branding elements or applications where the origin of the colour itself contributes to the product story may represent a different commercial proposition from trying to replace every conventional high-performance packaging pigment.

Whether that becomes the actual market strategy has not been announced.

For now, it remains one of the questions to watch.

A Successful Short Run Is Not the Same as Long-Run Stability

This is probably the next major production hurdle.

The project describes the August trial as operating successfully under production conditions.

But it does not disclose the length of the run.

That matters.

An ink may perform well for a short qualification run but encounter different problems after several hours of continuous flexographic printing.

Water evaporation can change viscosity.

Ink can dry on plates or anilox cells.

Foaming can develop.

pH can drift.

Colour variation can become more visible.

Press operators may need adjustments that were not obvious during a short trial.

None of those problems has been reported for the coffee-derived ink.

They are simply examples of why long-run data matter before a converter can regard a formulation as routine production material.

For a packaging plant, commercial success is not:

“we printed a good bag.”

It is:

“we printed thousands or millions of bags repeatedly, at the expected speed, with predictable waste, colour and downtime.”

That is a much higher threshold.

Raw-Material Consistency Could Become Just as Important as Press Performance

Conventional packaging pigments are manufactured to defined industrial specifications.

A side stream from another industry introduces a different supply question.

Coffee roasting produces material according to the needs of the coffee business, not the printing-ink business.

For the colourant producer, the challenge is therefore to turn that variable biological input into a sufficiently consistent industrial intermediate.

TAMK and its partners already identify quality consistency and raw-material availability at larger scale as areas that need to be resolved as the technology moves forward.

That is crucial.

An ink manufacturer cannot formulate every batch from scratch around an unpredictable raw material.

Eventually it will need specifications.

Colour strength within an acceptable range.

Moisture control.

Particle or soluble-colour characteristics appropriate to the chosen technology.

Storage stability.

Contaminant limits.

Batch traceability.

Perhaps other chemical parameters specific to the final process.

The exact specification for this technology has not been published.

But without consistency upstream, consistency on the printing press becomes much harder downstream.

The Coffee Supply Story Is More Complicated Than “There Is Plenty of Waste”

Coffee is consumed at enormous scale.

That makes coffee side streams sound automatically abundant.

But abundance does not equal industrial feedstock availability.

The relevant questions are narrower.

How much of the particular roasting side stream suitable for colourant production can be collected cleanly?

How geographically concentrated is it?

What extraction yield can BioInk obtain?

How much colourant is required for one tonne of finished ink?

How much ink would a paper-bag converter consume?

What happens when dozens of customers begin ordering it rather than one trial partner?

The project has not published those mass-balance figures.

Without them, it is too early to estimate how large a packaging-ink market this feedstock could support.

That is one of the differences between a circular-economy demonstration and an industrial raw-material business.

The demonstration asks:

Can we make something useful from it?

The business asks:

Can we make enough of the same thing, every week, at a price customers will pay?

Siegwerk’s Participation Changes the Commercial Meaning of the Project

Siegwerk’s role is therefore particularly important.

An academic team can develop a colourant.

A startup can develop extraction know-how.

A coffee company can supply feedstock.

A converter can provide a press.

But an industrial ink manufacturer has to translate that material into a formulation that fits existing customer requirements.

Siegwerk is one of the major global suppliers of packaging and label inks and coatings. Its involvement means the project is being evaluated inside the type of formulation and application environment the material would eventually need to enter commercially.

Paul Pain, Siegwerk’s Global Head of Water-Based Technology, said the trial demonstrated technical and commercial feasibility for further industrial scaling.

The phrase “for further industrial scaling” is the important qualification.

It means there is another stage to complete.

TAMK Calls It Commercial Scale. That Does Not Mean Commercialized.

TAMK’s September announcement says the technology has reached commercial scale on paper bags.

That wording needs context.

Commercial-scale equipment and a commercial product launch are different milestones.

The Hornung run demonstrates that the formulation can be used in an industrial manufacturing environment.

But no partner has announced:

a product name available to general customers;

commercial price;

sales volume;

dedicated manufacturing capacity;

contracted customer volumes;

or a market-launch date.

Natural Indigo Finland’s own current description of BioInk says the packaging technology is still at an early stage of development toward broader circular applications.

So the safest description today is:

industrial-scale validation with a pathway toward commercialization.

Calling the ink a fully commercial packaging product would run ahead of the evidence.

Paper Bags Were a Logical Place to Start

There is also a practical reason the project has advanced through fiber packaging.

Water-based inks are already well established in many paper and paperboard flexographic applications.

Hornung itself markets paper bags printed with water-based ink.

Paper therefore offers a relatively familiar production environment in which researchers can evaluate the new colourant without simultaneously having to solve every problem associated with film printing.

Flexible plastic packaging can introduce more demanding adhesion, surface-energy, drying and lamination requirements depending on the structure.

Paper bags provide a useful industrial benchmark.

If the formulation becomes stable there, researchers can decide whether it makes sense to move toward more technically demanding substrates and applications.

TAMK already says similar colourants could ultimately have applications more broadly across packaging.

But that wider application range remains future potential.

It has not yet been demonstrated.

Food Packaging Would Introduce Another Qualification Layer

Hornung is active in bakery and food-related paper packaging.

That makes another question likely to arise if the coffee-derived ink moves into those markets:

food-packaging compliance.

Printing on the outside of a bag does not necessarily mean an ink is intended for direct food contact.

Nevertheless, packaging used around food has to manage risks such as migration and set-off according to the final structure and intended use.

The current project announcement does not state that the coffee-derived ink has received a specific food-contact approval or migration qualification.

That does not mean it cannot be used.

It means the available information does not allow that conclusion.

If commercial expansion targets food bags, those application-specific tests will be another part of the qualification process.

The Most Valuable Part of the Coffee May Not Be the Colour

There is an interesting commercial possibility behind the project.

Conventional printing ink is usually invisible to the consumer as a supply-chain decision.

Nobody looks at a brown logo on a bag and asks where its pigment came from.

Coffee changes that.

If the package belongs to a coffee brand, bakery, café or food producer, the source of the colour itself can become part of the package story.

Coffee by-product from production.

Converted into colourant.

Used to print packaging.

That creates a very specific form of material storytelling.

It could potentially give the ink value beyond simply competing with a synthetic pigment on a cost-per-kilogram basis.

But that benefit will depend on the customer and application.

A packaging converter running commodity sacks is likely to evaluate the material very differently from a premium coffee brand looking for a visible circularity story.

So the eventual market may depend as much on where the colourant creates additional brand value as on whether it can technically replace a conventional pigment.

This Is the Part of Circular Packaging We Often Forget

Packaging sustainability discussions usually focus on the substrate.

Paper versus plastic.

Virgin versus recycled fiber.

Mono-material versus multilayer film.

Barrier coating.

Recycled content.

Pack weight.

But a printed package is a system.

Ink is part of that system.

A paper bag can be renewable and recyclable while still relying on pigments, binders and additives from different chemical supply chains.

The coffee project pushes circular-material thinking into a smaller component that receives far less public attention.

That does not mean ink is automatically the largest part of the package’s environmental footprint.

No evidence presented here supports that conclusion.

The value is different.

It demonstrates that packaging decarbonization and circularity do not have to stop when the base paper has been selected.

Suppliers can continue examining coatings, adhesives, inks and other functional materials.

The Next Trial Needs More Numbers

The August run answers one important question:

yes, the coffee-derived colourant can be formulated into a water-based ink and printed under real industrial conditions on paper bags.

The next stage needs to answer harder ones.

I would watch especially for data on production-run length, press speed, colour strength, batch consistency, ink consumption, rub and light resistance, raw-material yield and cost per kilogram of finished ink.

Those numbers would tell converters whether the technology is moving from an interesting material demonstration toward a purchasing decision.

A life-cycle comparison would also be useful.

If the project wants to claim reduced environmental impact compared with conventional pigments, the industry eventually needs data covering extraction, formulation, processing and feedstock logistics—not simply the fact that coffee waste is renewable.

The Hardest Transition Is Still Ahead

The coffee-derived ink project has already achieved something worth reporting.

It began with a side stream that was going to energy recovery.

Researchers extracted a usable colourant.

An ink company formulated it.

Printers moved it from laboratory work to flexographic proof of concept.

And in August, Hornung put the formulation through an industrial paper-bag production environment.

That sequence shows genuine progress.

But industrial packaging does not ultimately buy interesting chemistry.

It buys repeatable performance.

The commercial test will be whether the partners can produce the same colourant at larger volume, formulate it consistently, deliver it at an acceptable price and allow a printer to run it without treating every order as a development project.

If they can do that, the importance of the project will extend beyond coffee.

It would provide another example of how industrial biological side streams can move into higher-value packaging-material applications rather than going directly to energy recovery.

If they cannot, the August trial will still remain technically interesting—but it will not change what converters buy.

That is why the next milestone should not be another award. It should be a long production run with enough operating and economic data for a packaging printer to decide whether it would order the ink again.

For paper and flexible-packaging converters, that is the question worth asking:

Would you qualify a bio-based ink because of its renewable feedstock story—or only after it matches your current ink on colour, press speed, consistency and cost?

Last Updated on 10/09/2026 by Jota Machinery