A degradable multi-functional packaging based on chitosan/silk fibroin via incorporating cellulose nanocrystals-stabilized cinnamon essential oil pickering emulsion

Abstract

In this study, cellulose nanocrystals (CNC) exhibited a higher aspect ratio derived from Rosa roxburghii pomace (RRP), enabling them to effectively carry more charge and consequently form a Pickering emulsion (PE) of cinnamon essential oil (CEO) with enhanced stability. This mixture was then incorporated into a chitosan/silk fibroin (CS/SF) matrix to create an activated food packaging film successfully. Additionally, the cinnamon essential oil - Pickering emulsion (CEO-PE) prepared in this study exhibited superior compatibility with the film substrate. Scanning electron microscopy (SEM) results showed that the Pickering emulsion was uniformly distributed in the CS/SF matrix and formed microstructure-sized holes in the film. The FT-IR results revealed the formation of robust hydrogen bonds between the film components, indicating successful encapsulation of the CEO within the film. Furthermore, the incorporation of CEO-PE enhanced the film's mechanical and thermal stability, reduced the water vapor transmission rate, improved the film's DPPH radical scavenging and bacterial inhibition abilities, and imparted slow-release properties. Moreover, the prepared CS/SF/PE films had good degradation ability, which were basically decomposed by microorganisms within 14 d. And a life cycle assessment revealed that the CS/SF/PE film production reduces fossil resource consumption by more than 68% and global warming by more than 34% compared to film sourced from petroleum. In summary, this research demonstrated that CNC obtained from RRP can be successfully prepared as CEO-PE and combined with CS/SF matrix to prepare active food packaging film, which was promising films for extending the shelf life of fresh fruits.