Active cellulose acetate‐carvacrol films: Antibacterial, physical and thermal properties

Cellulose acetate (CA) is a low cost, biodegradable polymer obtained from renewable resources. The development of CA active films to reduce or inhibit microbial growth in food could increase food products' shelf‐life while decreasing the use of petroleum‐based non‐biodegradable polymers on food packaging. In this work, CA films containing carvacrol, a major antimicrobial compound in oregano essential oil, were obtained by solvent‐casting and extensively characterised. Results showed that carvacrol in concentrations up to 10 wt.% was homogeneously distributed on transparent and continuous films. Carvacrol had little effect on water barrier properties, elongation, and stiffness while decreasing the melting and glass transition temperatures of the CA films. The sustained release of carvacrol to the vapour phase was observed over 10 weeks. Films with 10 wt.% of carvacrol were bactericidal against Weissella viridescens and Pseudomonas fluorescens and extended in 2.8 times the shelf‐life for the vacuum‐packaged ham. The physical and antibacterial properties demonstrated the feasibility of CA films containing carvacrol for active packaging and food shelf life extension. Cellulose acetate antimicrobial films added of carvacrol were developed and characterized. These films containing up to 10% of carvacrol showed properties to be active packaging for extending food shelf‐life due to the sustained release of carvacrol to a vapour phase and antimicrobial action against food spoilage bacteria. It demonstrated the film activity for vacuum‐packaged ham.