Preparation, Characterization and Antimicrobial Activity of Sodium Alginate Nanobiocomposite Films Incorporated with Ε-Polylysine and Cellulose Nanocrystals

Abstract

Ternary nanobiocomposite films based on sodium alginate (SA) with cellulose nanocrystals (CNC) derived from shaddock peel and ε-polylysine (ε-PL) have been prepared and characterized. The tensile strength and Young's modulus of nanobiocomposite films increased from 51.18 to 67.68 MPa and from 4.8 to 7.6 GPa upon CNC loading from 0.5 to 2.5 wt %. The positive effects of the addition of CNC in SA matrix were also confirmed by reductions in water vapor permeability (WVP). SA-based nanobiocomposites showed significant antibacterial activity against Escherichia coli and Staphylococcus aureus influenced by the ε-PL content. The films exhibited homogeneous and cohesive structures, indicating strong interactions between the filler and matrix. In addition, the good dispersion of CNC in the SA matrix could increase the stability of ε-PL and promote the diffusion of the antimicrobial agent from the films. Practical Applications Chilled duck is an important raw material for making the sauce duck, roast duck, favor duck and it has a very broad consumer market. The chilled duck stability during storage can be enhanced by film-coating as a prominent technique, and therefore an nanobiocomposite film based on sodium alginate (SA) incorporation with ε-polylysine (ε-PL) and cellulose nanocrystals (CNC) derived from shaddock peel were prepared in this study. The film-coating has a good antibacterial effect on preservation of chilled duck. This study will find a successful packing method for chilled duck and improve the shelf life.