Alginates extracted from brown seaweed have a
variety of prospective applications such as thickeners, stabilizers,
or restructuring agents. Due to its properties as a natural
polysaccharide, alginate is very potential to be used as edible films
for food packaging purposes. Edible films are developed for food
protection being excellent barriers to gases but not to moisture.
Incorporation of antimicrobial agents into edible film
formulation can extend product shelf life and reduce the risk of
pathogenic bacterial growth on food. Therefore, this study was
aimed to develop an alginate based antibacterial edible film.
Antibacterial agent extracted from lemongrass leaves using
ethanol was employed. The study was conducted by varying the
addition levels of lemongrass ethanol extract to the alginate based
edible films, i.e. 0.5%, 1.0% and 1.5%. Before being added to the
alginate based edible films, the lemongrass ethanol extract was
investigated for its antibacterial activity. The edible films obtained
were analyzed in terms of physical, mechanical and chemical and
microbiological parameters, including thickness, water vapor
transmission rate (WVTR), brightness, tensile strength,
elongation, moisture content, water solubility and antibacterial
activity. Results showed that the higher addition levels of
lemongrass ethanol extract tended to produce alginate based
edible films with lower WVTR and brightness value as well as
higher elongation, moisture content and water solubility. Edible
film added with lemongrass ethanol extract resulted in this study
demonstrated antibacterial activity against Staphylococcus
aureus. The addition of lemongrass alcohol extract at 0.5% was
considered as a recommended concentration level for producing
alginate based antibacterial edible films.