Algae-shield SCOBY leather: development of Kombucha SCOBY-based vegan leather

SCOBY leather is a bio-composite material derived from bacterial cellulose produced through kombucha fermentation, with strong potential as a sustainable alternative to synthetic leather. While SCOBY leather possesses good inherent mechanical properties, it exhibits key limitations such as high hydrophilicity and poor water resistance, which restrict its durability in humid environments. This study aims to enhance the water resistance and functional performance of SCOBY leather through biopolymer-based modification. The proposed innovation, Algae-Shield SCOBY Leather, utilises an Interpenetrating Polymer Network (IPN) approach by incorporating sodium alginate and glycerol into the cellulose structure. This is followed by calcium chloride spraying to induce cross-linking, thereby improving structural stability and resistance to water penetration. This method replaces conventional surface treatments such as wax or oil coating with a more sustainable and structurally integrated approach. Results demonstrate a significant improvement in water resistance and flexibility of the treated SCOBY leather, accompanied by a slight reduction in tensile strength. Stress–strain analysis indicates increased elongation, suggesting enhanced flexibility suitable for practical applications. The use of seaweed-derived alginate also supports the “blue carbon” concept and aligns with Sustainable Development Goals (SDGs 9, 12, and 13). In conclusion, Algae-Shield SCOBY Leather presents strong potential as an eco-friendly material for the textile and fashion industries, particularly in applications requiring flexibility and water resistance, with promising commercial potential.