In January 2021, the NPR-funded collaborative project Kera was launched to evaluate the feasibility of valorizing chicken feathers as a new biopolymer. Four partner companies Micarna SA, Centravo AG, Alma Packaging AG and Maillefer SA collaborated with the PICC (Plastics Innovation Competence Center), the ChemTech Institute of the HEIA-FR and the Berner Fachhochschule.
In the European Union, around 15 million tons of poultry meat are transformed each year, generating approximatively 3 million tons of feathers. Typically, this “not fit for human consumption” by-product is either converted into low-nutritional value animal feed, fertilizer or incinerated. Not only are these options unsustainable, but they also destroy valuable materials and miss an opportunity to contribute to the circular economy. With about ninety percent protein content (keratin), poultry feathers are potentially a rich and renewable source of valuable and high-performance biopolymers.
The Kera project was structured in 4 parts:
- study of chemical processes allowing the extraction of keratin from chicken feathers
- evaluation of optimal processing conditions to produce biopolymer products by extrusion or injection moulding
- preliminary study of the consumer perception of this new material and product
- preliminary study of the environmental impact of this biopolymer
For the project, the starting material was “feather meal” i.e., processed feathers. This process involved an elevated temperature treatment and grinding of the feathers into a powder. It was found that the process modified the keratin structure an induced partial crosslinking of hydrolyzed keratin fragments and the additional feather components (e.g., lipids). Accordingly, it was difficult to extract pure keratin or process feather meal directly using conditions established in the literature. Nevertheless, feather meal could be used as a filler in combination with bio-based polyesters making very hard but brittle injection molded parts. The extracted keratin could be processed into a film, but still contained cross-linked residuals that led to a brown colored product with and offensive odor. The preliminary consumer study, based on an on-line questionnaire with 100 participants, indicated that there was not a priory concern raised towards the use of chicken feather biomass for packaging applications and consumer perception was overall positive. The preliminary life cycle assessment indicated that using certain solvents for keratin extraction is not recommendable and that the overall environmental impact is positive provided some extraction procedures and processing conditions are optimized.
The Kera project was finalized in October 2021 and the generated knowledge is very valuable for a follow-up project starting from chicken feathers directly. Rudolf Koopmans, Kera project manager and PICC director added in conclusion “the vast amounts of biomass wasted including chicken feather are an important source of natural polymers that can replace non-renewable fossil-fuel based plastics. Moreover, and in the context of the urgent need to achieve a zero-emission carbon neutral economic system for the world, the present project leads the way towards a distributive and renewable sustainable economy from locally produced feedstock”.