Functional and antimicrobial properties of cellulose acetate films incorporated with sweet fennel essential oil and plasticizers.

Cellulose acetate (CA) films with sweet fennel essential oil (FEO) were evaluated for possible changes caused by the incorporation of 5, 10, 20 and 30% glycerol. The results show that the incorporation of different concentrations of plasticizer caused an increase in thickness, water vapor transmission rate (WVTR), tensile strength (TS), besides altering the optical properties and demonstrating possible chemical interaction with the CA matrix (Fourier transform infrared (FTIR)). Scanning electron microscopy (SEM) images revealed that the addition of glycerol caused morphological changes on the surface and internal region of all films. As for antimicrobial activity, the FEO was effective for Staphylococcus aureus and Escherichia coli. However, all films evaluated did not show activity in inhibiting these microorganisms. Therefore, it is believed that the FEO may have some incompatibility with the CA matrix, being trapped between the polymer chains. Therefore, the results suggest that the incorporation of glycerol caused changes in the functional properties of all films, although it did not result in measurable antimicrobial effects.

Evaluation of the Oxidative Status of Salami Packaged with an Active Whey Protein Film.

Active packaging aims to prolong food's shelf-life by directly interacting with the packaged food. This type of packaging is characterized by having the active agent incorporated into the package polymer, such as antioxidant additives, that will gradually migrate from the package polymer to the packed food and, consequently, delay food's natural lipid oxidation. In this study, the efficiency of an active whey protein film incorporated with a rosemary extract on retarding the lipid oxidation of salami slices was evaluated. The lipid oxidation of the salami was measured by the thiobarbituric acid reactive substances (TBARS) assay and hexanal monitorization. Also, a sensory analysis on the salami packaged for 60 and 90 days was performed. The active film was able to delay the salami's lipid oxidation for, at least, 30 days. The samples packaged with the active film revealed a bitter taste related to the rosemary extract and a bit sweet from the WP and the glycerol.