New biodegradable food packaging enhances food safety

The new material contains fibres which kill off E.coli, listeria and fungi, and keeps food fresh for longer than plastic. Scientists hope to commercialise the technology within the next few years.

Scientists have announced a breakthrough in 'smart' food packaging by creating a packaging material that is waterproof, biodegradable, sustainable and kills microbes that are harmful to humans.

According to the scientists, from Nanyang Technological University, Singapore (NTU) and Harvard TH Chan School of Public Health in the USA, the material is made from zein (a corn protein), starch and other naturally derived biopolymers. It is then infused with natural antimicrobial compounds, including oil from thyme and citric acid.

Laboratory experiments suggest that when exposed to an increase in humidity or enzymes from harmful bacteria, the fibres in the packaging kill off E.coli, listeria and fungi.  Material can reportedly endure several such exposures and potentially last for months.

“In an experiment using strawberries, those wrapped in the packaging stayed fresh for seven days, compared to counterparts kept in mainstream fruit plastic boxes, which only stayed fresh for four days.”

Long-term, it has the potential to be used for a large variety of products, including ready-to-eat foods, raw meat, fruit and vegetables. In an experiment using strawberries, those wrapped in the packaging stayed fresh for seven days before developing mould, compared to counterparts that were kept in mainstream fruit plastic boxes, which only stayed fresh for four days.

Professor Philip Demokritou, Adjunct Professor of Environmental Health at Harvard Chan School, who co-led the study, said: "Due to the globalisation of food supply and attitude shift towards a healthier lifestyle and environmentally friendly food packaging, there is a need to develop biodegradable, non-toxic and smart/responsive materials to enhance food safety and quality.

“In this study, we used biopolymers, non-toxic solvents and nature-inspired antimicrobials, which can not only be used to enhance food safety and quality but also to reduce the use of non-biodegradable plastics at global level and promote sustainable agri-food systems."

The scientific team hope to scale up their technology in collaboration with an industrial partner with the aim of commercialisation within the next few years. The results of the study were published in the peer-reviewed academic journal ACS Applied Materials & Interfaces.

Kate Thompson, CIEH Director described it as an exciting development. “It has the potential to reduce the use of plastic food packaging and minimise food waste, contributing to ambitious government targets,” she said.

However, she cautioned that an important consideration will be its suitability for different uses and ensuring there are no unintended consequences associated with its use that could compromise human, animal or environmental health.