Helping shrink the footprint of construction, research into sustainable alternatives to traditional materials finds exciting new uses for an ingredient more often associated with baking and brewing, than architecture.
Innovating around organic and renewable options, researchers at Chalmers University of Technology, Sweden, have developed a new, entirely bio-based material from a somewhat unexpected source: yeast.
The material is 3D-printed and customised for use in architectural and interior design elements that are currently made from non-renewable or fossil-based materials, such as plaster, plastic or synthetic textiles.
Residual products repurposed
Given the large proportion of global emissions and resource consumption attributable to the construction sector, the need to discover and develop renewable, resource-efficient material alternatives is urgent.
In a new study, therefore, researchers from Chalmers are investigating how industrial residual products can be used to create new materials that can boost circularity in architecture and the built environment.
Providing a prime example of both rethinking and repurposing, the newly developed material consists of baker’s yeast, cellulose fibres from wood, alginate from algae, glycerol from plants, and water. Together, the ingredients form a kind of hydrogel – a soft, jelly-like, malleable material – that can be 3D-printed.
The innovation lies in the use of living materials, says Malgorzata Zboinska, Professor at the Department of Architecture and Civil Engineering at Chalmers, and leader of the recently published study:
“Essentially, this is about creating an architectural material made entirely from organic, renewable ingredients. By combining biomaterials with digital manufacturing, we can take a novel approach to both the design and production of architectural components.”
Potential applications are multiple and could include architectural and interior design features such as daylight modulating and sunlight protecting screens, room partitions or wall systems.
3D-printed zero-waste design
The project combines design, materials innovation and advanced manufacturing technology. The first part of the process is similar to baking, but in slightly reverse order. First, the yeast is heated to deactivate it, and then the various ingredients are mixed together to form a smooth mass.
The architectural elements can then be manufactured using pressure-based 3D printing, carried out at room temperature. This requires neither energy-intensive heat nor additional support structures.
Access to advanced manufacturing tech is key, explains Yagmur Bektas, a doctoral student at the Department of Architecture and Civil Engineering at Chalmers, and co-author of the study:
“3D printing makes it possible to create complex shapes without producing waste. We can design and manufacture the material directly – with a high degree of control over its shape, texture and material distribution.”
Minor tweaks to the material formula tailor its transparency, colour and surface texture to suit various different interior applications. In the long term, the yeast material could also become an environmentally friendly alternative to plastics and other petroleum-based products, such as synthetic textiles.
Depending on the exact composition, the material takes on a natural hue that ranges from yellow to brown tones. The colour can be altered using natural pigments or pigment-producing, colourful yeast strains. It is also possible to design different patterns, vary the transparency of the material and the feel.
From baking and brewing, to building
As a material component, yeast has not been widely explored as yet in architecture, notes Zboinska:
“Yeast grows exponentially. It does not require strictly controlled environments and is not particularly sensitive to contamination. As it consists of single-celled organisms, we can produce a more homogeneous, predictable material.”
What makes the new formula unique is that the yeast is not employed in the usual way for fermentation, but as biomass. It becomes a robust component, giving the material its volume, stability and strength.
Future opportunities may exist to upcycle by-products from industries such as brewing and agriculture, some of which get discarded. Residue unsuited to use as food or animal feed could work in architecture.
Designing with nature
Ultimately, unlike traditional building materials, which are designed to last as long as possible, bio-based materials offer new ways of thinking about sustainability and material cycles. The yeast-based material is biodegradable and can return to nature after use – a key aspect of circular design.
These fundamental differences call for a sector-wide mindset shift, adds Zboinska:
“This challenges the traditional notion that materials must last forever, or at least have as long a physical life cycle as possible. Instead, we can think in terms of shorter life cycles and even view the ageing or degradation of the material as part of the design.”
Self-healing on the horizon
Whilst results show great potential, further research is needed before the material can be used widely in buildings. Future studies will assess key properties like strength, fire safety and moisture performance, as well as scaling-up digital manufacturing, plus developing stronger and more robust structures.
The new 3D-printed prototypes do though pave the way for progress, concludes Professor Zboinska:
“The future of architectural Engineered Living Materials (ELMs) is very exciting, with great potential to customise them to perform a variety of functions. This could, for example, involve self-healing materials or materials that purify the air by neutralising harmful substances and pollutants.”
Recipe of ingredients
In terms of specifics of composition, the newly developed material consists of baker’s yeast (dry yeast), cellulose fibres (from wood), alginate (from brown seaweed), glycerol (from plants) and water.
Each component contributes a specific function to the final mix. Glycerol acts as a plasticiser and provides flexibility. Alginate contributes to the dimensional stability required for 3D printing. Structurally, cellulose further contributes to dimensional stability and provides tensile strength when the material is under load.
Crucially, the yeast acts as a binding agent for all the ingredients and gives the mixture its viscosity. Before mixing ingredients to form a hydrogel, the researchers deactivate the yeast to stabilise the material. Then the hydrogel is 3D-printed using air pressure and left to dry at room temperature.
Science, academia and government funding
Chalmers University of Technology in Gothenburg, Sweden, conducts research and education in technology and natural sciences at a high international level. First founded in 1829, The university has 3100 employees and 10,000 students. It offers education in engineering, science, shipping and architecture. With scientific excellence as a basis, Chalmers promotes knowledge and technical solutions for a sustainable world.
The scientific article on Novel 3D printable yeast-based materials for architectural applications was originally published in the international journal Frontiers of Architectural Research. The authors are Yagmur Bektas, Malgorzata A Zboinska, Cecilia Geijer, Tiina Nypelö and Zeinab Hefny. At the time of the study the researchers were based at three different departments at Chalmers University of Technology in Sweden, and at Aalto University in Finland. The research has been funded by the Swedish Energy Agency.
Further Reading:
- More about Chalmers University of Technology; and the new research paper on yeast-based materials;
- Also on SustMeme, Biotech startup to grow rubber from dandelions;
- Also on SustMeme, Funders back cellulose roll-out at industrial scale;
- Also on SustMeme, Reusable packaging cuts construction site waste;
- Also on SustMeme, Innovative leather alternative made from beer waste;
- Also on SustMeme, Scottish facility wins £500K grant to support circular cement;
- Also on SustMeme, Renting clothes model fits best in niche markets (featuring Chalmers);
- Also on SustMeme, Wood-based water tech removes 80% dye pollutants (featuring Chalmers);
- Also on SustMeme, Hydrofoils can help electric ferries fly across the sea (featuring Chalmers).
Check out the full archive of stories on the SustMeme Built Environment Channel, now available to Sponsor.
