Preparation and Antibacterial and Physical Properties of Antibacterial Membrane Containing Zinc and Ε-Polylysine

In this paper, an edible antibacterial film incorporated with zinc gluconate (ZG) and Ε-polylysine (Ε-PL) as antibacterial agents was prepared with sodium alginate aqueous solution (2.5 g/100 mL) containing gum arabic (1 g/100 mL)and glycerol (2 g/100 mL). The effects of the addition of the two antibacterial agents on the color, microstructure, water vapor permeability, mechanical properties and antibacterial activity of the film were investigated, and the efficacy of the film in preserving the quality of raw meat was evaluated. The results showed that after adding Ε-PL and ZG, the color of the antibacterial film was yellowish; the water vapor permeability decreased, and the tensile strength, elongation at break and antibacterial activity increased. The antibacterial effect of the film with Ε-PL at 2.60 mg/mL and ZG at 0.39 mmol/L on Escherichia coli O157:H7 and Staphylococcus aureus was significant, and it had relatively good physical properties. The thickness, tensile strength, elongation at break and water vapor permeability were (0.097 6±0.000 6) mm, (10.75±0.36) MPa, (29.34±1.03)% and (3 633.75±62.03) g/(m2•d), respectively. After 24 h of storage at 37℃, the number of bacteria in meat wrapped with the Ε-PL/ZG antibacterial film was much lower than that of the control group, indicating that the Ε-PL/ZG antibacterial film had a good bacteriostatic effect. This study provides a theoretical basis for the application of zinc and Ε-PL-loaded antibacterial film. © 2020, China Food Publishing Company. All right reserved.