‘Baked’, printed, ready – premiere of architecture made from yeast

Researchers at Chalmers University of Technology, Sweden, have developed a new, entirely bio-based material from a somewhat unexpected ingredient: 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. These may be daylight modulating and sunlight protecting screens, room partitions or wall systems.

The construction sector accounts for a large proportion of global emissions and resource consumption, which means there is a great need for renewable, resource-efficient alternatives. In a new study, a research team from Chalmers investigate how industrial residual products can be used to create new materials that can contribute to greater circularity in architecture and the built environment.

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.

“I’ve always been interested in the combination of architecture and living materials, and essentially this research 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,” says Malgorzata Zboinska, Professor at the Department of Architecture and Civil Engineering at Chalmers, and leader of the recently published study.

Zero-waste design through 3D printing

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, which is carried out at room temperature. This requires neither energy-intensive heating nor additional support structures.

“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,” says Yagmur Bektas, a doctoral student at the Department of Architecture and Civil Engineering at Chalmers, and co-author of the study.

Interior applications

With minor adjustments to the formula, the material’s transparency, colour and surface texture can be altered, making it well suited for interior applications such as daylight modulating and sunlight protecting screens, wall panels or room partitions.

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 composition of the formula, 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 how it feels. 

From baking and brewing to building

The use of yeast as a material component is something that has not yet been explored in architecture.

“Yeast grows exponentially. It does not require strictly controlled environments and is not particularly sensitive to contamination. Because it consists of single-celled organisms, we can produce a more homogeneous, predictable material,” explains Malgorzata Zboinska.

What makes the researchers’ new formula unique is that the yeast is not used in the usual way for fermentation, but acts as biomass. It then becomes a robust component that gives the material its volume, stability and strength. Malgorzata Zboinska also highlights the potential of using by-products from industries such as brewing and agriculture, as some of these products are often discarded. Residue that cannot be used as food or animal feed could therefore be used in architecture.

Designing with nature

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.

“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,” says Malgorzata Zboinska.

Self-healing or purifying materials on the horizon

Although the results show great potential, further research is needed before the material can be used widely in buildings. Future studies will assess key properties such as strength, fire safety and moisture performance, as well as scaling up digital manufacturing and developing stronger and more robust structures.

“The future of architectural ELMs, or Engineered Living Materials, 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. What we have achieved so far is an important first step towards establishing a completely new type of architectural material. You could say that we are laying the foundations for future developments that combine sustainability, functionality and design in entirely new ways,” says Malgorzata Zboinska.

Factfile

The 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 material.

Glycerol acts as a plasticiser and provides flexibility, whilst alginate contributes to the dimensional stability required for 3D printing.

Cellulose further contributes to dimensional stability and acts as a structural component that provides tensile strength when the material is under load.

The yeast acts as a binding agent for all the ingredients and gives the mixture its viscosity. Before mixing the ingredients to form a hydrogel, the researchers deactivate the yeast, which is necessary to stabilise the material. The hydrogel is 3D printed using air pressure and left to dry at room temperature until it achieves its final shape.

More about the study:

The scientific article ‘Novel 3D printable yeast-based materials for architectural applications’ has been published in 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 (grant numbers P2022-00865, P2024-02409).