Chitosan-gelatin composite hydrogel antibacterial film for food packaging

• Published in: International journal of biological macromolecules 2025-01, Vol.285, p.138330, Article 138330
• Main Authors: Li, Chaoqun, Yang, Yongyan, Zhang, Ruiting, Wang, Jia, Zhong, Shuangling, Cui, Xuejun
• Format: Article
• Language: English
• Subjects: Antibacterial; antibacterial properties; breasts; chickens; Chitosan; electron microscopy; Escherichia coli; Food packaging; food safety; Gelatin; Hydrogel; hydrogels; light transmission; lysine; polymers; shelf life; Staphylococcus aureus; total volatile basic nitrogen
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2024.138330

Antibacterial hydrogel film can serve as food packaging materials to prevent bacteria growth and spread, thereby extending shelf life and improve food safety. In this study, an efficient antibacterial hydrogel film (CLG) was prepared with chitosan, lysine, and gelatin. The light transmission of the CLG hydrogel film was over 80 % in the visible region, facilitating the observation of chicken breast storage conditions. Additionally, the swelling ratios of the hydrogel films decreased with increasing gelatin concentration, from 145.7 g/g (CLG1) to 92.6 g/g (CLG2) and 81.5 g/g (CLG3). This reduction was attributed to the denser network structure formed by the interaction between gelatin and the CL polymer. The Scanning Electron Microscopy (SEM) showed that the water-absorbed CLG hydrogel had a unique sponge shape. Moreover, the CLG hydrogel film exhibits high antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In a practical storage experiment, the CLG hydrogel film extended the shelf life of chicken breast by up to 4 days compared to untreated samples, while effectively reducing total volatile basic nitrogen (TVB-N) levels. This hydrogel film is expected to become a promising food packaging material. •Lysine-modified chitosan enhances the antibacterial activity and cross-linking efficiency of the hydrogel film.•The high optical transmittance (>80%) of CLG hydrogel film, enabling easily observe food storage conditions.•Incorporation of gelatin making a denser network structure reduces the swelling ratio, enhancing the film's stability.•The CLG hydrogel film extends the shelf life of chilled chicken by up to 4 days.•The recyclable and re-moldable CLG hydrogel film demonstrates strong potential as food packaging material.