UK researchers develop ‘green’, edible film

The project is a joint work between the University of Nottingham and China’s Hubei University of technology

University of Nottingham researchers have developed 100% biodegradable and edible plastic food packaging made from plant carbohydrates and proteins as an alternative to fossil-based plastics materials.

The project is a joint work between the University of Nottingham and China’s Hubei University of technology, and is led by Saffa Riffat, whose research group works on innovations in sustainable materials, energy and building technologies.

The team’s research includes investigations into the structure and functionality of sustainable natural materials such as plant polysaccharides (carbohydrates) and proteins to develop advanced materials for applications in buildings, energy technologies, packaging and beyond.

Using a special technical approach, the team is working on plastic films derived from konjac flour and starch, cellulose or proteins that are fully edible and harmless if accidentally eaten by human beings or animals.

This will address the health issues associated with microplastics and other plastic waste that make their way into the food chain.

The researchers have found that plant carbohydrate and protein macromolecules bond together into a special network structure during the film-forming process. The network structure provides the film with a required mechanical strength and transparent appearance for the film to be used as packaging materials.

The project is jointly investigated by Marie Curie research fellow, Fatang Jiang, an expert in biodegradable polysaccharide materials for moisture control, thermal insulation and infiltration.

He recently joined the University of Nottingham from Hubei University of Technology in China, where part of the study is being worked on.

“While plastic materials have been in use for around a century, their poor degradability is now known to cause serious environmental harm. This has led to more stringent recycling targets and even bans coming into force,” explained Riffat, who is also a fellow of the European Academy of Sciences and president of World Society of Sustainable Energy Technologies.

The issue prompted Riffat and his team to work on finding degradable solutions to tackle plastic pollution.

“In addition to being edible, degradable, strong and transparent, the packaging materials we are working on have low gas permeability, making them more air tight,” Riffat added.

This feature cuts moisture loss, which slows down spoilage, and seals in the flavour, contributing to food preservation and safety.

The primary market for these plant-based packaging materials will be superstores and food supply chains. The research team is also aiming to advance the technology for general packaging in construction, express delivery and magazines.

The project, currently supported by the £220k (€247,000) Horizon 2020 Marie Curie fellowship, will last two years with the potential to extend for another three to five years if further funding is secured.