Danish researchers are teaming up with the Carlsberg brewery and a packaging company to develop a biodegradable paper bottle. But it’s a project full of challenges.
It would really benefit the environment if beer could be sold in containers made of paper rather than conventional materials such as glass, plastic and metal. That’s why Thomas Howard, a researcher at Technical University of Denmark (DTU), and colleagues have teamed up with the packaging company EcoXpac to develop a ‘Green Fiber Bottle’ for the Danish brewery Carlsberg.
“We have set the bar high and stated that we’re looking for a bottle that can be used for beer. Of course, we will also look into other, less demanding areas of application, but our ambition is to create a beer bottle,” says Howard.
And it’s quite a challenge the partners have taken on. First, the bottle and cap must be able to withstand the pressure from the carbon dioxide in beer. Second, it must be possible to stack, transport, and handle the new bottle without breaking it. On top of that, it must be possible to produce the new bottle quickly in large numbers – given that Carlsberg is the intended purchaser.
Making a bottle in six seconds
“EcoXpac already has a very promising process,” Howard says. “But at present, the problem is that it takes a very long time to make a bottle. If we are to live up to Carlsberg’s requirements, we need a bottle that can be made in just six seconds. At the same time, we have to keep the energy consumption low, otherwise the solution will not be sustainable.”
The prototype is made from recycled newspapers, or paper mache, but the team is also looking at other types of fibre. The paste is poured into a mould, where it has to dry. In a traditional mould, this takes much longer than six seconds, and the material tends to collapse. The team is therefore working with a process involving a porous mould, which makes it possible to force all the water out of the paper using vacuum. Howard estimates that the new process will enable them to achieve the critical production time of six seconds.
Bringing value back to the ecosystem
The bottle is being developed as a sustainable alternative to plastic bottles, and a life cycle analysis will highlight the environmental benefits. In one context, the advantage is obvious: if a bottle evades the deposit system – say, if it’s discarded into the environment – it won’t do any harm there because it’s biodegradable. Other benefits have yet to be demonstrated, but the intention is that the new bottle brings value back to the ecosystem, ideally through the collection and composting of the bottles.
But plenty of parameters will need to fall into place before we might see paper bottles of beer appearing on the shelves. And that’s precisely the point and the charm of the project, according to Howard.
“We have to live up to all sorts of requirements, as design and quality are also crucial in determining whether the bottle succeeds on the market. That’s what makes this such a fascinating research project. It’s rare for us to have the opportunity to develop a completely new product using a completely new material and a completely new production system. We’re now in a situation where we need all of our modelling designs to align perfectly to hit the ‘sweet spot’ where everything comes together in a coherent whole.”
Howard hopes the team will hit this point within the project’s duration of three years – three years that are also set to reveal whether the world is ready to drink beer from paper bottles. Howard has no doubts: “If everything goes according to plan, I’m sure we can make it. And I would love to be able to drink beer from a paper bottle in three years from now.”
Innovation Fund Denmark has contributed funding of DKK 15 million to the project.
More on beer innovation: Smart beer.