Development of a chicken feet protein film containing essential oils

To prepare an edible film, after extraction of protein from chicken feet, chicken feet protein (CP) films were prepared using various types of plasticizers, and their physical properties were evaluated. Incorporating more sorbitol than glycerol as a plasticizer in the CP film made the film more rigid, and a 3:2 ratio (w/w) of glycerol-sorbitol was optimal. To render the film antimicrobial and antioxidative, marjoram (MA), coriander (CO), and clove bud oil (CL) were incorporated. The type of essential oil affected the mechanical properties of the CP film, and the film containing CL had the most desirable physical properties: a tensile strength of 6.49 MPa, an elongation at break of 20.91%, and a Young's modulus of 313.49 MPa. The antimicrobial and antioxidant activity was the highest for the film containing CL. When applying the CP film during food packaging, sliced cheddar cheese was wrapped with a CP film containing CL. Consequently, using a CP film containing CL inhibited microbial growth and delayed lipid oxidation in the sliced cheddar cheese during storage. Therefore, a CP film containing CL can be used in antimicrobial and antioxidative packaging for food products.