We're the first brand to release Brewed Protein™ products from New Zealand, but what are they? In this journal entry, we take a deep dive into the entirely new fibre featured in our Spring Summer ’26 collection.
The only man-made protein fibre to be successfully industrialised, this groundbreaking new product has its origins in the organic, combining natural molecules with technological innovation to create something that could change the face of fashion.
So, what exactly is Brewed Protein™ fibre?
Instead of coming from sheep or silkworms, this luxurious material starts with something as humble as sugarcane. Using a fermentation process (not unlike brewing your favourite kombucha), Spiber’s technology transforms sugar into a new kind of Brewed Protein™ fibre, one that mimics the softness of cashmere, the sheen of silk, and the loft of wool.
At its core, Brewed Protein™ is a plant-based, lab-crafted material made with precision fermentation. Think of it as nature-inspired innovation, gently guided by science.
A new kind of luxury, inside and out
We often talk about how clothes look, but what about how they feel?
Brewed Protein™ fibres are crafted to be scaleless, meaning they're less likely to pill and stay smoother over time. They also offer low prickliness, making them gentle on the skin. And thanks to their protein structure, they naturally absorb and release moisture, offering breathable comfort with every wear.
This isn’t just a win for your wardrobe, it’s a thoughtful step forward for people, animals, and the planet.
A smaller footprint, a bigger impact
According to Spiber’s most recent life cycle assessment, compared to traditional cashmere, Brewed Protein™ fibre production can result in:
- 99% less land use
- 97% less water use
- 82% less eutrophication (the process that harms waterways due to nutrient overload)
Please note that this result is a future projection based on a scenario where the Thai polymer plant is operated at a full capacity. For more details, please see the LCA highlight document.
And when it comes time to say goodbye? The material breaks down naturally. The length of disintegration can vary depending on the final fabric structure and weight, but tests on the undyed, woven fabric showed it broke down into an undetectable size within months.
Rooted in community and sustainability
What sets Brewed Protein™ apart isn’t just what it’s made from, but how it’s made.
Spiber sources sustainably certified sugarcane from local growers in Thailand, putting transparency and traceability at the centre of their process. Their collaboration with producers—farmers, processors, and community stakeholders alike—echoes a deeper intention: that true sustainability is never a solo journey.
It’s about relationships. It's about respect. It's about rethinking the way things are made, from the ground up.
Looking ahead: garments that last, values that endure
While Brewed Protein™ fibres are still relatively new, they’re already showing us a different path forward, one where innovation isn’t just about performance, but purpose.
Spiber has made deliberate choices along the way, sometimes opting for materials or processes that might carry a slightly higher footprint now, in exchange for creating longer-lasting garments. It’s not about quick wins, but about thoughtful trade-offs that serve a greater good.
What does your version of luxury look like?
In a world where materials matter more than ever, Brewed Protein™ fibre invites us to think differently about what we wear. To look beyond the label. To choose comfort with conscience.
So next time you're wrapped in something soft and beautiful, ask yourself: What story does this fabric tell?
And more importantly, what kind of story do I want to be a part of?
