Physicochemical Properties of Chitosan Films Incorporated with Honeysuckle Flower Extract for Active Food Packaging

Abstract Active food packaging films based on chitosan and honeysuckle flower extract ( HFE ) were developed. The effects of the HFE incorporation at different levels on physical and mechanical properties (density, moisture content, opacity, color, water solubility, water vapor permeability, tensile strength and elongation at break) of chitosan film were investigated. The antioxidant activity of the chitosan/ HFE films was characterized in terms of 2,2‐diphenyl‐1‐picrylhydrazyl free radical‐scavenging activity. The antimicrobial activity of the chitosan/ HFE films against E scherichia coli was determined by the agar diffusion method. The results indicated that the incorporation of HFE enhanced the antioxidant and antimicrobial activity of chitosan film and also improved the moisture barrier properties of chitosan film. Compared with the chitosan control film, the chitosan/ HFE films had darker appearance, higher water solubility and lower tensile strength and elongation at break. The obtained chitosan/ HFE films showed great potential to be used for active food packaging. Practical Applications Chitosan‐based films and coatings have attracted considerable attention because of their biodegradability, antimicrobial activity, nontoxicity and versatile physicochemical properties. Honeysuckle flower extract (HFE) is extracted from honeysuckle, the flowers of Lonicera japonica Thunb. Because honeysuckle contains active components that have a wide spectrum of biological and pharmacological activities, such as antibacterial, antiviral and antioxidant activity, incorporating HFE into chitosan film should enhance antimicrobial and antioxidant activity of the film. On the other hand, the addition of HFE may affect other properties of chitosan film related to packaging applications. Through investigating effects of incorporating HFE on physicochemical properties of chitosan film, a more effective chitosan/HFE film/coating with optimized properties for food stuff packaging could be obtained.