Biodegradable Active Packaging: Exploring the Antimicrobial Efficacy and Compostability of Chitosan-Based Films

The overarching purpose of this experiment is to create an active packaging component that has both antimicrobial and biodegradable properties specifically designed for poultry food products. For the scope of this study, the packaging component created would theoretically be used in conjunction with another material, such as a poultry tray which are commonly used for fresh poultry products. Based on the scope and purpose of this experiment, biopolymer films and coatings were considered after the initial literature review. Due to the goals of the packaging component, chitosan, a polysaccharide shown to have antimicrobial properties and an inherent ability to biodegrade, was the material chosen to make the packaging component. A standalone chitosan film was the packaging component created, due to chitosan’s ability to make a sturdy film. For the first research objective, three treatments of chitosan-based films (1.5, 2.0, and 2.5% chitosan w/v) were created and select properties of the film (water contact angle, thickness, water vapor transmission and permeation rate, moisture content, tensile strength, and percent elongation) and film solution (viscosity and pH) were analyzed because of the relevancy of these properties as a food packaging component. The second research objective was to investigate the antimicrobial efficacy of the created chitosan films. The three treatments of chitosan-based films were qualitatively tested against pathogenic Salmonella enterica due to its prevalence in fresh poultry products. The antimicrobial efficacy of the three treatments of the chitosan film solutions were measured using a spot on lawn assay. The spot on lawn assay results showed that the chitosan-based films resulted in zones of inhibition where the solution was in direct contact with the agar, whereas it was unclear whether the chitosan films were capable of Salmonella inhibition. The final research objective involved testing the biodegradability of the three treatments of chitosan-based films under industrial composting conditions. The amount of biodegradation was measured by collecting captured carbon dioxide from the composting vessels weekly for seven weeks. Based on the chitosan materials’ initial carbon and collected CO2 the 1.5, 2.0, and 2.5% chitosan films had a percent biodegradation of 55.91, 47.66, and 78.98%, respectively.