Physically programmed vegan leather emulating the mechanical and sensory characteristics of animal leather from once-discarded gluten

Abstract

The production of animal-derived leather raises substantial environmental and ethical concerns, prompting the search for sustainable alternatives. However, most synthetic leathers are not biodegradable and fail to replicate the tactile and mechanical properties of natural hide, while bio-based films often exhibit poor toughness/elongation and hydration sensitivity. Here, we report a chemical toughener-free process that transforms wheat gluten—a widely available but underutilized plant protein—into durable and biodegradable vegan leather. The facile process combines heating and UV exposure to induce depth-gradient protein denaturation of only plant-based ingredients. In the first stage, thermal conditioning promotes uniform distribution of glutenin and gliadin and optimizes hydrogen bonding, enhancing structural integrity. Subsequent brief, high-intensity heating and UV treatment initiate thiol-mediated crosslinking among cysteine residues and oxidized amino acids, forming a molecular network. The resulting material exhibits an exceptionally high toughness of 4.7 MJ m⁻³ and comparable water resistance to animal leather. The protein-based structure replicates the frictional feel, pliability, and surface micro-texture of natural leather, providing a comparable aesthetic and tactile experience. This material is fully soil-degradable, has a reduced carbon footprint by up to 13-fold compared to animal leather, provides waterless dyeing, and is even edible by insects. Therefore, the vegan leather developed in this study offers a scalable and eco-friendly alternative to conventional leather.