Unlocking branched cutin via sudden supercritical water hydrolysis of tomato peel†

Abstract

This study presents a novel approach to unlock and enrich branched cutin from tomato peel waste using sudden supercritical water hydrolysis. Cutin, the structural polyester of the plant cuticle, offers exceptional properties for biomaterials developments, however, conventional extraction methods often degrade its intricate three-dimensional network, limiting its potential applications. Utilizing sudden supercritical water hydrolysis (SCWH) with a reaction time of approximately one second, non-cutin components are hydrolyzed while preserving and enriching the native cutin structure. Characterization of the cutin-rich solid revealed the absence of a detectable glass transition temperature or melting point, indicating the maintenance of its native polymeric architecture phenomena typically observed when cutin is isolated as a mixture of monomers. Furthermore, mechanical testing revealed high rigidity under more stringent conditions, with a measured Young's modulus of 0.7 GPa. This rapid and efficient process not only valorizes agricultural and industrial residues but also enables the development of sustainable, bio-based materials. The successful preservation and enrichment of native cutin open new avenues for its application in advanced biomaterials, offering a promising alternative to fossil fuel-derived polymers.