Properties and antimicrobial activity of polyvinyl alcohol-modified bacterial nanocellulose packaging films incorporated with silver nanoparticles

An environmentally friendly antimicrobial film was developed by incorporating silver nanoparticles (AgNPs) into bacterial nanocellulose (BNC) via reduction (R) and UV-assisted (UV) methods. By mixing with 3 wt% polyvinyl alcohol (PVA) solution, the elongation at break of the films was improved 20 times that of pure BNC film. The films exhibited higher oxygen barrier capacity with slightly improved water vapor permeability. Antimicrobial activities against Escherichia coli O157:H7 were observed from both R and UV films with up to 7 and 3 log CFU/mL of reductions in liquid medium and on raw beef, respectively. A raw beef shelf-life study suggested that the films were able to inhibit the growth of naturally present bacteria for at least 10 days at 4 degrees C. The findings of this research indicate the potential of the AgNP/PVA/BNC films for applications in food packaging.