Food-grade plastic can be made from seaweed, a sustainable and biodegradable option that could reduce oil-based and artificial sources.

In a paper published in the journal Algal Research, academics at Aberystwyth University’s Institute of Biological, Environmental and Rural Sciences (IBERS) show that seaweed extracts can be turned into an alternative biodegradable plastic.

In 2022, plastics used for packaging accounted for just under a third of the 400 million tonnes of plastic produced around the world. Plastic packaging also has a major impact on the natural environment with 15 billion kilogrammes of plastic waste entering the marine environment every year.

Combining seaweed extract alginate with other biological compounds has been shown to strengthen the new plastic, and make it more elastic, so it can be used for food wrappings.

Dr Jessica Adams from IBERS at Aberystwyth University: “It is good news for the planet that seaweed grown in the UK can be used to create more sustainable plastics. Seaweed has so many special and unique properties, not least because films produced from alginate are completely biodegradable, making this a completely circular product. Seaweed can be used to form thin, transparent plastic-like sheets that have many valuable traits, making them excellent candidates for replacing food wrapping.”

---