Nano-chitosan-nisin composite membrane: Physicochemical properties and its impact on sturgeon storage quality

In this study, gelatin was used as the film-forming matrix, and nanoparticles were introduced into chitosan-Nisin film (Ch-Nisin) to prepare nano-chitosan-Nisin composite film (Nch-Nisin). The physicochemical properties of the film and its preservation effect on the quality of sturgeon during storage were investigated. The tensile strength values of Nch-Nisin film and Ch-Nisin film were 113.74 MPa and 101.70 MPa, respectively, and the corresponding elongation at break values were 31.43% and 26.30%. The transmittance results showed that Nch-Nisin had higher light blocking ability than Ch-Nisin. SEM observation showed that there were many undulating surfaces on the Nch-Nisin film. XRD and FTIR analysis confirmed the compatibility and stability between the nanoparticles and the film matrix. Thermogravimetric analysis showed that the Nch-Nisin film had good thermal stability. The Nch-Nisin membrane showed higher DPPH and ABTS antioxidant activity and antibacterial properties than the Ch-Nisin membrane. Preservation trials were then conducted on sturgeon using PE film as a control, which indicated that both Ch-Nisin and Nch-Nisin films effectively suppressed the increase in pH, TBARS, TVB-N, and TVC values and protein oxidation. Notably, Nch-Nisin exhibited a more pronounced inhibitory effect compared to Ch-Nisin. The findings contribute a theoretical foundation for advancing eco-friendly food preservation film technologies. • Nanocomposite films were successfully prepared using the tape-casting method. • The addition of nanoparticles changed the physical properties of the films. • Nanocomposite film has the potential of food packaging film.