Antibacterial and antioxidant plant-derived aldehydes: A new role as cross-linking agents in biopolymer-based food packaging films

In recent years, biopolymer-based food packaging films have emerged as promising alternatives to petroleum-based plastic food packaging films. Various additives have been explored to enhance their properties, and one such group of additives is natural plant aldehydes. These aldehydes are commonly employed to improve the antibacterial and antioxidant properties of biopolymer-based food packaging films. However, their potential role as cross-linking agents is often overlooked in these applications. This work introduces the properties of commonly used natural plant aldehydes in biopolymer-based food packaging films. Specifically, it summarizes the effects of natural plant aldehydes such as cinnamaldehyde, vanillin, and others on the properties of biopolymer-based food packaging films. Furthermore, the application of biopolymer-based food packaging films functionalized with natural plant aldehydes in food preservation is discussed. This work concludes that various natural plant aldehydes serve as effective antimicrobial agents and antioxidants. They can not only physically interact with biopolymers but also undergo chemical cross-linking reactions with some polymers through Schiff base reactions and Michael addition reactions, thereby further improving the comprehensive properties of the film.