Influence of ZnO nanoparticles on slow release of essential oil from polimeric matrix

Abstract

Biopolymer emulsions were processed in the form of thin films for application in active food packaging. Active packaging is defined as material designed to release active components into food or absorb them from food in order to extend durability or to maintain/improve packaging conditions and extend shelf-life of food. We synthesized emulsion based on biodegradable polymers (pectin, gelatin, chitosan) with addition of active components -essential oils and ZnO nanoparticles (NPs). By introducing essential oils in the polymer matrix, with the addition of certain emulsifiers, it comes to encapsulation of oil droplets and the formation of a homogeneous emulsion. Thin films were fabricated by mold casting or spraying of the emulsions on a substrate. The slow release of an essential oil from the polymeric matrix was determined by UV-vis spectrophotometry. It was shown that polymers with addition of nanoparticles provided a prolonged action of active components. Surface morphology of the films was characterized by atomic force microscopy (AFM), and it was noticed that nanoparticles were mainly accumulated around oil droplets, which additionally contributed to a slow release of the active components.