Enhancing food safety and extending shelf life with cost-effective cypress essential oil for packaging films

Bio-active packaging films from cellulose acetate incorporated with cypress essential oil (Cyp) have been developed. Thus, cellulose acetate (CA), which is a biodegradable and renewable polymer has been used as an alternative to petroleum-based polymers. Cellulose acetate films were prepared via a solvent casting method incorporating 0, 10, 30, and 60% (w/w) of Cyp. The purpose was to evaluate the possible changes caused by the Cyp on the properties of the packaging films. Different methods and technics have been used to characterize these films. The antibacterial and antioxidant properties of the films were also analyzed. FTIR and XRD analysis indicated that Cyp was homogenously distributed in the films. Meanwhile, TGA analysis demonstrated that the addition of Cyp had an impact on thermal-oxidative properties of the films. The CA/Cyp films showed excellent biodegradability in soil after 60 days, with a percentage loss of 87.07% by mass, and improved mechanical properties with tensile strength and elongation-at-break of 8.1 +/- 0.2 MPa and 16.6 +/- 0.2%, respectively. Water absorption and water solubility values for CA/Cyp films ranged from 76.62 +/- 0.91% to 21.95 +/- 0.57% and from 1.29 +/- 0.35 to undetectable levels, respectively. The results displayed that antibacterial activity against Escherichia coli and Staphylococcus aureus increased as the percentage of Cyp increased in the cellulose acetate films. Moreover, the free radical scavenging activity of cellulose acetate films was improved by increasing the Cyp concentration. These results indicate that cellulose acetate films containing a low-cost essential oil like Cyp have potential for use as active packaging for foods.