Di-aldehyde starch crystal: A novel bio-crosslinker for strengthening the structure and physio-chemical properties of gelatin-based films

In this study, 2,3-dialdehyde starch crystal was used as a novel and low-toxicity bio-crosslinker to design composite gelatin-based films with both superior mechanical and barrier properties. The starch crystal containing aldehyde group was fabricated via periodate oxidation as an efficient cross-linker to reinforce the gelatin based bio-composite films. X-ray photoelectron spectroscopy (XPS) and (1)Hydrogen nuclear magnetic resonance (H-1-NMR) revealed that di-aldehyde starch crystal (Di-SC) could react and covalently cross-link with the amine group of gelatin molecules via C=N chemical bond. The tensile strength of gelatin film containing 10% di aldehyde starch crystal (G/Di-SC-10%) exhibited a tensile strength of 70.8 MPa, which was 967% higher than that of neat gelatin film (6.7 MPa). Additionally, the hydrophobic properties, thermal stability and surface morphology of G/Di-SC-10% were significantly enhanced, and so was its UV-barrier shield efficiency. Our results indicate that the new gelatin/di-aldehyde starch crystal bio-composite film has potential practical applications in the edible film-based packaging industry.

Automated summary

This study utilized 2,3-dialdehyde starch crystal as a bio-crosslinker to design composite gelatin-based films with superior mechanical and barrier properties. The XPS and H-1-NMR analyses confirmed the effectiveness of di-aldehyde starch crystal in enhancing the performance of gelatin films, particularly the 10% di-aldehyde starch crystal content.