Novel LDPE/chitosan rosemary and melissa extract nanostructured active packaging films

Abstract

The increased global market trend for food packaging is imposing new improved methods for the extension of shelf-life and quality of food products. Active packaging, which is based on the incorporation of additives into packaging materials, is becoming significant for this purpose. In this work, nanostructured low-density polyethylene (LDPE) was combined with chitosan (CS) to aim for a food packaging development with an increased oxygen permeability barrier and higher antimicrobial activity. Furthermore, essential oil extracts as rosemary (RO) and Melissa (MO) were added to this packaging matrix in order to improve its antioxidant properties and vanish food odor problems. The novel nanostructured active packaging film was tested using laboratory instrumental methods, such as thermogravimetry (TG), Fourier-transform infrared (FTIR) spectrometry, the X-ray diffraction (XRD) method, a dilatometer for tensile properties (DMA), and an oxygen permeation analyzer (OPA). Moreover, laboratorian tests according to ASTM standards were carried out for the estimation of water sorption, water vapor permeability, overall migration, and, finally, the antioxidant properties of such films. The experimental results have indicated that the final material exhibits advanced properties. More specifically, chitosan addition was observed to lead to an enhanced oxygen and water-vapor permeability barrier while the extracted essential oil addition led to enhanced tensile strength and antioxidant properties.