Preparation of bitter almond polypeptide / chitosan composite film and its preservation effect on cheese

To explore the improvement of the physical and chemical structure and bacteriostatic efficacy of chitosan composite film by adding bitter almond antibacterial peptide and to expand the application of bitter almond antibacterial peptide in the field of food preservation, the bitter almond peptide / chitosan degradable composite film was prepared with chitosan and gelatin as film-forming agents, and the cheese was wrapped. The effect of the additional amount of bitter almond antibacterial peptide on the properties of the chitosan composite film was investigated, and the physical properties, antibacterial activity, and fresh-keeping effect of the composite film on cheese were studied. Results showed that adding bitter almond antibacterial peptide could enhance the antibacterial activity of chitosan film, improve the opacity of the film, reduce water vapor permeability, and maintain elongation at break and tensile strength. Meanwhile, the bitter almond polypeptide / chitosan composite film could more effectively inhibit the growth of microorganisms, prolong the shelf life of cheese, maintain its original color, flavor, and quality, and have the potential to be further developed into food preservation packaging. This study demonstrates that the bitter almond polypeptide / chitosan composite membrane plays an important role in protecting the quality of cheese, which provides a theoretical basis for improving the quality stability of cheese products. © 2025 China National Research Institute of Food and Fermentation Industries Co. Ltd. All rights reserved.