Bay Leaves Extracts as Active Additive for Food Protective Coatings | JoVE Visualize

Area of Science:

Food Science and Technology
Material Science
Microbiology

Background:

Postharvest losses in perishable fruits like strawberries significantly impact food availability and economic value.
Natural compounds from plant extracts offer potential for developing functional food packaging materials.
Edible films can act as barriers to moisture, gases, and radiation, extending fruit shelf life.

Purpose of the Study:

To develop and characterize edible films incorporating bay leaf extract for perishable fruit preservation.
To evaluate the antimicrobial, physical, and barrier properties of these novel composite films.
To assess the efficacy of bay leaf-infused edible films in reducing postharvest losses in cultivated strawberries.

Main Methods:

Ethanolic bay leaf extract was prepared and analyzed for chemical composition, phenolic content, and antioxidant activity.
Antimicrobial activity was tested against bacteria (Escherichia coli, Bacillus cereus) and yeasts (Candida glabrata, Saccharomyces cerevisiae).
Edible films were fabricated using various polymers (carboxymethyl cellulose, gum Arabic, polyvinyl pyrrolidone, polyvinyl alcohol) with different bay leaf extract concentrations (0-15% wt.).
Film properties including water vapor permeability, transparency, and UV blocking were evaluated.
In vivo tests were conducted on cultivated strawberries to assess mass loss reduction using optimized film formulations.

Main Results:

Bay leaf extract exhibited significant antioxidant activity (75.06%) and phenolic content (11.8 ± 0.4% wt.).
The extract demonstrated antimicrobial properties, with a minimum inhibitory concentration of 0.65 mg/mL against Bacillus cereus.
Composite films showed reduced water vapor permeability (up to 4.3 × 10^-7 g·Pa^-1·m^-1·h^-1) and effective UV blocking (>99.9%).
Impregnation with polyvinyl alcohol and 15% wt. bay leaf extract significantly reduced strawberry mass loss by 22% after 6 days.

Conclusions:

Bay leaf extract possesses valuable antimicrobial and antioxidant properties suitable for food packaging applications.
Developed edible composite films offer excellent barrier properties against water vapor and UV radiation.
Polyvinyl alcohol-based films with 15% bay leaf extract are effective in preserving strawberry quality and reducing postharvest losses, presenting a viable alternative to conventional packaging.