Preparation and characterization of chitosan quaternary ammonium salt/konjac glucomannan film incorporated with CTAB for blueberry preservation

In this research, an antibacterial film was prepared using chitosan quaternary ammonium salt (CQAS), konjac glucomannan (KGM), and cetyltrimethylammonium bromide (CTAB). The effects of varying CTAB concentrations on the microstructure, physical properties, and antibacterial properties of the films were investigated. The results showed that when 0.15 % (w/v) CTAB was added to chitosan quaternary ammonium salt/konjac glucomannan film (CQAS/KGM), the tensile strength, antibacterial activity, and antioxidant properties of the chitosan quaternary ammonium salt/konjac glucomannan/CTAB film (CQAS/KGM/CTAB) improved significantly ( p < 0.05 ). Blueberries coated with CQAS/KGM/CTAB film exhibited significantly better preservation than the control group, including reduced loss of total soluble solid content, anthocyanin, total phenol, and total flavone, and inhibited MDA production. These results suggest a great potential for the application of CQAS/KGM/CTAB films in the active packaging of blueberries. • Chitosan quaternary ammonium salt/Konjac glucomannan/CTAB composite films were developed for blueberry preservation. • CTAB enhanced the UV-blocking performance and the mechanical properties of films. • The films showed strong antibacterial activity against Staphylococcus aureus and Escherichia coli. • The films significantly improved the quality of blueberries within 20 days compared to the control.