Belgian circular biotechnology is shaping the future of sustainable fashion. Discover how Citribel in Tienen is transforming sugar molasses into mycelium used in high-end fashion materials.
When Taylor Swift recently stepped out in New York wearing striking boots and a matching handbag, few would have guessed that a key ingredient behind that luxury look originated in Tienen, Belgium. Yet hidden within the elegant design was a material story rooted in Belgian circular biotechnology and fungal innovation.
At the heart of it all is the Belgian company Citribel, one of the world’s leading producers of citric acid. Citribel is a quiet pioneer in transforming industrial by-products into materials that are now redefining sustainable fashion.
The Belgian ingredient behind a global style moment
The boots and handbag worn by Swift were designed by Stella McCartney, a long-time advocate of cruelty-free and sustainable fashion. The material itself is a vegan alternative to snakeskin, developed under the brand YATAY M by Italian fashion innovator Coronet. (More pictures here).
What links this high-fashion moment back to Belgium is MycaNova mycelium – the network of fine fungal threads supplied by Citribel. Originally a by-product of citric acid surface fermentation, MycaNova mycelium is now being used in cutting-edge biomaterials used in various applications.
What exactly is mycelium, and why does it matter?
Despite common associations, this story is not really about mushrooms. It is about mycelium: the underground, thread-like structure that allows fungi to grow, communicate, and exchange nutrients.
From a material science perspective, Citribel’s MycaNova mycelium is remarkable:
- Eco-friendly: It is 100% animal-free and 100% bio-based.
- Customizable: Can be tailored to meet specific design and performance needs.
- Lower carbon footprint: An end product can have a 12-30% reduced carbon footprint.
- High quality and performance: MycaNova meet industry standards and can be used in a wide variety of applications.
In nature, mycelium even plays a role in carbon sequestration, reinforcing its sustainability credentials. For innovators looking to replace leather or petroleum-based synthetics, it offers a credible and scalable alternative.
Citribel’s circular biotechnology ecosystem
Citribel’s innovation begins with something humble: sugar molasses, a sidestream of the sugar industry. Rather than treating this as waste, the company uses it as the primary feedstock for its surface fermentation process. (Citribel is the only producer worldwide using surface fermentation for citric acid production; it enables the generation of significant volumes of mycelium.)
Here is the simplified flow:
- Surface fermentation: Sugar molasses nourish a specific fungal strain, which converts sugars into citric acid while simultaneously producing mycelium.
- Carefully controlled conditions: Across 184 fermentation chambers, variables such as temperature, humidity, and surface tension are continuously monitored to ensure consistency and quality.
- Separation and downstream processing: After fermentation, citric acid and mycelium are separated. The citric acid continues through purification, crystallisation, and drying, while mycelium is dried and milled into a versatile raw material.
From industrial by-product to high-end fashion
Citribel’s MycaNova mycelium travels from Belgium to Italy, where Coronet processes it into YATAY M, a next-generation biomaterial designed specifically for fashion applications. Unlike early “eco-leather” alternatives, YATAY M is engineered for real-world use:
- Produced at scale and supplied in rolls
- Comparable chemical and physical performance to established materials
- Made using FSC or GRS-certified components
- Designed to be workable, durable, and even pleasant to handle
When adopted by designers such as Stella McCartney, these materials move from lab and factory floor into the public eye – sometimes via global icons like Taylor Swift.
Another example is Lies Mertens, an innovative Belgian designer who has created a collection of MycaNova handbags that reflect the specific mycelium patterns.
Why this matters beyond fashion
While the fashion connection captures attention, the deeper story is about Belgium’s strength in circular biotechnology.
Citribel has been operating in Tienen since 1919, continuously refining its fermentation expertise. What makes the company distinctive today is not just technical excellence, but mindset: treating production as a living ecosystem where every output has potential value.
This approach aligns closely with Europe’s broader goals around carbon neutrality, waste reduction, circular economy models, and cross-sector innovation. In this context, mycelium-based fashion is not a novelty – it is a proof point.
A quiet Belgian success story with global reach
Belgium is not always the loudest voice in sustainability debates, but stories like Citribel’s show how deep industrial knowledge, patience, and circular thinking can lead to unexpected global impact.
From sugar molasses to fermentation chambers, from fungal threads to fashion runways, this is innovation that grows organically – quite literally.
And next time a global pop star steps out in a statement accessory, there is a fair chance that a small part of Belgium’s circular biotechnology heritage is woven into the design.
I created Discovering Belgium in 2011 to share the country’s hidden stories, fascinating places, and remarkable people. Through articles, photography, and audio walks, I share discoveries that reveal Belgium beyond the obvious. Hope you enjoy this site.
Fascinating, Denzil! I wasn’t aware of this new development in mycelium-based fashion products.
It may be your next pair of boots Rosaliene!
Who knows?!
Amazing!