Packaging has manifold roles in food industry. Ideally, it should protect food from contamination, mechanical damage, light, humidity and other factors that can cause spoilage and rotting. Recently, active and intelligent packaging were introduced in order to prolong shelf-life and improve food safety. Development of active and intelligent packaging is mainly based on application of nanotechnology in food packaging. Bio-nanocomposites are materials consisting of biopolymer matrix and nanofillers which exhibit at least one dimension on the nanometer scale. The main advantages of using biopolymers in food packaging is biodegradability, non-toxicity and abundant renewable sources. On the other hand, nanofillers can improve mechanical, thermal, barrier and some other properties or even bring new functional properties such as antioxidative and antimicrobial properties.

The aim of our research was to develop biopolymer films and coatings, with incorporated active components, such as lemongrass essential oil and metal oxide nanoparticles, for application in antimicrobial packaging. Physicochemical and functional properties of the several formulations of emulsions and dispersions were compared. Natural polymers (chitosan, pectin, and gelatin) were used because of their availability, biodegradability, biocompatibility, nontoxicity, and safety for human health and the environment. Lemongrass (Cymbopogon citratus L.) essential oil in combination with TiO2 or ZnO nanoparticles were used as the active components incorporated in the biopolymer matrix. Processing parameters and composition of bio-nanocomposites were optimized in the way to provide nanoencapsulation of essential oil and its slow release during substantial time period. The synergistic effect of essential oil, biopolymer matrix and nanoparticles was confirmed.