You'll typically find beer packaged in glass and aluminum, materials strong enough to keep a lid on the carbonated beverage. These materials can also be collected, processed, and used to make new beverage containers. A paper container, made from sustainably sourced wood fibers, fully recyclable and biodegradable would not only be a breakthrough for beer packaging, but also other applications with similar requirements, such as soda, spirits and personal care products.

Beer maker Carlsberg, along with packaging specialists BillerudKorsnäs and ALPLA, formed a partnership to develop such a bottle.

This partnership has reached a milestone, creating a set of prototypes capable of holding beer dubbed the Green Fiber Bottle, a project they launched back in 2015.

Unveiled during the C40 World Mayors Summit in Copenhagen, Denmark, the new functional prototypes are made from sustainably-sourced fiber, are fully recyclable and made with an inner barrier that allows the bottle to contain the beverage successfully. One bottle uses a thin, recycled PET polymer film, while the other prototype uses a bio-based PEF polymer film. The bottles will be used to test the barrier technology as Carlsberg continues towards its ultimate goal of making a 100% bio-based, polymer-free bottle.

“We continue to innovate across all our packaging formats, and we are pleased with the progress we’ve made on the Green Fiber Bottle so far,” said Myriam Shingleton, Vice President Group Development at Carlsberg Group via a press release. “While we are not completely there yet, the two prototypes are an important step towards realizing our ultimate ambition of bringing this breakthrough to market. Innovation takes time, and we will continue to collaborate with leading experts in order to overcome remaining technical challenges, just as we did with our plastic-reducing Snap Pack.”

In addition to the new Green Fiber prototypes, new partners Coca-Cola, Absolut, and L’Oreal were announced, joining Carlsberg in a new community aimed at uniting leading companies and experts that share a vision of advancing sustainable packaging called Paboco, or Paper Bottle Company.