Olive Mill Waste Water Added Alginate Films for Antibacterial Food Packaging Applications

Abstract

Alginate films are edible and biodegradable polysaccharides which are new food packaging candidates, however they do not have any antibacterial activity, which limits their applications. On the other hand, olive mill waste water (OMWW), which contains biophenols in its composition is a powerful antimicrobial material. The goal of the current study was to produce antibacterial alginate films making use of olive mill waste water for packaging applications and to investigate the physical and antibacterial properties of the prepared films. In this work, olive mill waste water and glycerol added alginate films were prepared by the solvent cast method. Their antibacterial properties were investigated by the agar disc diffusion method, mechanical properties by tensile stretching and optical properties by UV-visible spectrometry. Based on the results, pure alginate films and alginate-glycerol films didn’t exhibit antibacterial activity whereas olive mill waste water addition resulted with antibacterial activity. In terms of mechanical properties, addition of olive mill waste water decreased the tensile strength by 50% and increased the elongation at break values of alginate films by more than 100% compared to pure alginate films and by 100% compared to alginate glycerol films, resulting in soft and flexible films. Dark colored, UV barrier, antibacterial films are especially appropriate for UV protective biodegradable food packaging applications. This is the first application of olive mill waste water in a useful product.

Keywords Antibacterial food packaging, olive mill waste water, alginate films, biodegradable

DOI: 10.7176/JSTR/6-07-07