Antimicrobial and biodegradable packaging

On average, each European citizen produces around 160 kg of packaging waste each year; around 19% of it is plastic.

Cutting down packaging waste and reducing the number of foodborne illnesses are both prime concerns for the food and beverage manufacturing industry. Now Kaunas University of Technology (KTU) Department of Polymer Chemistry and Technology researchers are solving these two problems in one go.

They are creating biodegradable food packaging materials that also keep food fresh for longer. The team, headed by Paulius Pavelas Danilovas, is investigating the use of cellulose composites enriched with active components.

With the goal to create a biodegradable package, which could help to keep food fresh for longer, various essential oils were added to the cellulose-based film. The active components in clove oil were found to be effective in tying free radicals and this oil proved efficient in enriching packaging with anti-oxidising qualities. While this effect helped to keep food fresh for longer the package was not antimicrobial.

“To achieve antimicrobial effect, we added ionic silver particles to the cellulose-based packaging. The results we achieved were quite unexpected — the silver particles made the packaging film more elastic and stronger,” said Danilovas.

The film, which is enriched with silver, inhibits the growth of microorganisms and its antimicrobial properties remain active for considerable lengths of time.

One limitation of the cellulose-based film is that cellulose does not have thermoplastic properties.

“We are excited to have found composites, which not only allow cellulose to turn into fluid condition, but also are non-toxic, which is very important in all products related to food handling,” said Danilovas.

The modified cellulose packaging degrades in nature in around two years. The production of the packaging prototype has been tested in a Lithuanian enterprise.

The commercialisation of biodegradable active food packaging products, which could replace the non-recyclable plastics, is in the near-future plans of the researchers.