Evaluation of Mechanical, Antioxidant and Antimicrobial Properties of Edible film Containing Myrtle Berries Extract

Background: In the last decades, consumers have become more health conscious and their demand for foods without synthetic preservatives has increased. The use of edible films as carriers of natural antimicrobial agents provides a novel way to improve the safety and shelf-life of ready-to-eat foods. These films can reduce surface microbial populations and reduce the need for synthetic packaging materials. Edible films can be made from polysaccharides, proteins, lipids or a combination of them. Objective: For this purpose, different polymer combinations containing starch, sodium alginate, poly(vinyl-alcohol) or whey protein at different ratios were studied and the mechanical properties were determined. Methods and Results: All the films studied exhibited promising mechanical properties, with those prepared using a combination of starch, sodium alginate, PVA and whey protein at a ratio of (32/32/32/4) showing the highest Elongation at Break value. The selected film was incorporated with myrtle berries hydro-alcoholic extract as a known source of many compounds which can be used in both the food industry and for medical purposes, primarily as antimicrobial agents. The antioxidant and antimicrobial properties of the prepared film were evaluated. Our results indicate that the total phenolic content is 18.20 ± 2.56 mg GAE/g of dry weight correlated with IC50 OF 2.14 ± 0.12 mg/mL. Pronounced antibacterial activity was observed against both Staphylococcus aureus and Pseudomonas aeruginosa, whereas Escherichia coli was completely resistant. Conclusion: In conclusion, the edible film containing myrtle berries hydro-alcoholic extract could provide a new strategy to enhance microbial safety and shelf-life of foods.