Keynote
Designing antimicrobial polymer nanocomposites for food packaging

Roughly, one-third of the food produced globally for human consumption is lost or wasted. These losses occur at all stages of the food value chain and across all types of food. Active packaging already plays a vital role in preventing wastage and further innovation is imperative to streamlining the food supply chain. We focus on the development of antimicrobial packaging containing plant-derived antimicrobials e.g., essential oils (EOs), as an alternative strategy to reduce microbial contaminations. However, the volatile nature of EOs presents a major challenge in their incorporation into polymers by conventional high-temperature processing techniques. Herein, we employ Halloysite Nanotubes (HNTs) as efficient nano-carriers for EOs. Taking into consideration their unique hollow tubular structure, we use a pre-compounding step in which HNTs/EOs hybrids are produced, to promote loading and encapsulation of the EOs into the nanotubes. This pre-compounding step imparts enhanced thermal stability to the EOs, allowing for their subsequent melt compounding with various polymers such as low-density polyethylene. The resulting polymer nanocomposites exhibit outstanding antimicrobial properties with a broad spectrum of inhibitory activity against Escherichia coli, Listeria innocuain biofilm, and wide range of fungal molds. Their antimicrobial effectiveness is also successfully demonstrated in complex model food systems. This superior activity, compared to other studied EOs-containing films, is induced by the significantly higher EOs content in the film as well as its slower out-diffusion from the hybrid system. Thus, these new active polymer nanocomposites present an immense potential in controlling microbial contaminations and biofilm related adverse effects, rendering them as excellent candidate materials for the development of custom-made active packaging for the food and postharvest industries.

This project has received funding from the European Union`s Horizon 2020 research and innovation programme under grant agreement No 720815.