Physical, mechanical, and bioactive properties of edible film based on sodium alginate enriched with Lythrum salicaria L. extract

Abstract

An active film was developed by incorporating Lythrum salicaria L. ethanol extract (LSE) into sodium alginate at concentrations of 0.5, 1.0, 1.5, and 2.0% v/v. The effects of LSE on the microstructure and physicochemical and bioactive properties of the films were evaluated. The ABTS antioxidant capacity of film samples was found to be 7.56–160.61 μmol TE/mg film, and the DPPH radical scavenging capacity was estimated to be 2.51%–38.44%. Films containing LSE showed remarkable antibacterial activity against both gram-positive and gram-negative strains. Moreover, it was also determined during the 14-day storage of raw ground meat samples under refrigerator conditions that, in comparison to the control films, the LSE-added active film samples were more effective on the microbiological characteristics of the product. It was determined that, in samples with LSE addition rate exceeding 0.5%, extract was not homogeneously distributed within the polymer matrix and decreased the tensile strength. Practical applications The presented study provides elaborate characterization analysis of the edible film to prove the effectiveness of using herbal extract incorporated active edible films for shelf life extension and packaging of raw meat. It was found that, in relation with the amount of LSE additive in films, the hydrophilic character of films increased, and it increased the biodegradability of film in the soil. In conclusion, it can be stated that sodium alginate-based edible films enriched with LSE have the potential of use in food packaging.