Researchers from the Harvard John A Paulson School of Engineering and Applied Sciences (SEAS) and the Harvard TH Chan School of Public Health in the US have developed a biodegradable food packaging system that could reduce food waste and health risks.

Inspired by battlefield medicine, professor Kit Parker and his Disease Biophysics Group developed a fibre manufacturing platform called Rotary Jet Spinning (RJS) to develop antimicrobial fibres intended for wound dressing.

RJS works similarly to a cotton candy machine, in which a liquid polymer solution is first poured into a reservoir before the solution is pushed out through a small opening with a centrifugal force as the device spins.

Once the solution leaves the reservoir, the solvent evaporates, which in turn solidifies polymers to form fibres.

The idea to translate the wound dressing research to food packaging came from a collaboration with Philip Demokritou, former co-director of the Centre for Nanotechnology and Nanotoxicology at Harvard’s Chan School.

Food packaging has some of the same purposes as wound dressings, including sustaining tissues, safeguarding them against bacteria and fungi, and controlling moisture.

To make the fibres food-safe, the team chose a polymer known as pullulan, a tasteless, edible, naturally occurring polysaccharide used in breath fresheners. 

The pullulan polymer was first dissolved in water before being mixed with a range of antimicrobial agents, including citric acid, thyme oil and nisin.

Once the solution is spun in an RJS system, the fibres are deposited directly onto a food item.

Parker said: “One of the biggest challenges in the food supply is the distribution and viability of the food items themselves.

“We are harnessing advances in materials science and materials processing to increase both the longevity and freshness of the food items and doing so in a sustainable model.”