Potato starch and seaweed: UK designer creates super sustainable polymer that leaves no trace

30 May 2019 --- Imagine a packaging material that can lower carbon emissions, reduce plastic litter, cut food waste and improve gut health when eaten, while being very much affordable. That is what UK packaging designer, Jayne Cunningham, set out to do on the road to creating SEAsoning – an edible, compostable and transparent bioplastic made from potato starch and seaweed. Here, Cunningham speaks to PackagingInsights about the inspiration behind SEAsoning, its benefits as a sustainable packaging material and the next steps for the project.

Cunningham was struck by the lack of sustainable packaging solutions at her local food market. She wanted to create a bioplastic from renewable sources which could achieve the necessary barrier protection to package FMCG products, including peel-on fruit, vegetables, dried foods and drinks.

“The materials choice followed a journey of research which had me reading about innovative non-mineral oil polymers. I wanted to see if I could combine materials found in coastal areas – perhaps even ones that people eat – and I discovered that seaweed and starch from potato peelings can be combined to create an effective polymer,” she explains.

The non-mineral oil polymer is edible and designed to taste great – sweet, with the addition of a salty seaweed taste, Cunningham says. SEAsoning edible polymer naturally preserves vegetables and fruit thanks to the naturally occurring preserving enzymes in seaweed and the natural gas barrier that the polymer provides.SEAsoning designer, Jayne Cunningham

She points out that potato peels are the second most wasted food source in the world. The waste peel from potatoes used to manufacture and make crisps, chips, ready meals and other fast-convenience foods are often discarded and sent to landfill.

“Research suggests that potato starch found in the peel is resistant and, if eaten, slows the absorption of refined sugars and balances insulin levels, reducing sugar craving. The starch also has a positive effect on the good gut bacteria, further reducing sugar craving and promoting good mental health,” she notes.

“Meanwhile, seaweed is definitely a resource to get giddy about in terms of responsible-farming. This superfood plant cleanses the water of chemicals that surrounds it, metabolizes greenhouse gases and breathes out oxygen,” Cunningham adds.

Seaweed grows abundantly throughout the world’s oceans and reduces CO2 levels. When combined with potato starch, an edible bioplastic can be created that has human health benefits and also planetary health benefits when composted.

The seaweed was foraged from the local coastline and dried by hanging it up. To ensure the seaweed was of food grade, this was done by a professional forager. The potato starch was purchased in powder form from a local health shop, although this process could have been done at home.

To create the bioplastic, Cunningham ground the seaweed into powder and mixed it with room temperature water, the potato starch powder, gum and vinegar. The gum and vinegar are needed to add flexibility and change the molecular structure of the “wonky” starch chains. Then boiling water is added and the ingredients blended.

The high-speed mixing returns the stress ball-like mass to a liquid form. The material was dehydrated initially on sheets on top of a radiator and, later, to speed up the process, in a slow cook oven, which acts as a food dehydrator.

Cunningham notes that she expected a transparent material to be formed through the application of heat to the ingredients.The seaweed and potato starch bioplastic has numerous qualities, including transparency.

“One of the obvious limitations of this material is the lack of moisture tolerance,” Cunningham notes. “This can be improved by replacing water with milk, but that takes away the material transparency.”

What next for the project? Commercialization can only be achieved with outside investment, but Cunningham remains optimistic about the future of the material.

“My intention for the material is for it to be blow-molded into shape, like current plastics on the assembly line, or to be made into flat surface sheets using similar methods to that of making pasta sheets,” she says.

“I am fascinated by this polymer as there are so many possible applications. SEAsoning could be part of the solution in the drive for more sustainable packaging options. This material is much more than that though – it can help with the depletion of agricultural soil and improve human gut health. After all, it is created through the use of simple materials from waste streams, and these are materials that give back to the earth when composted,” she concludes.

By Joshua Poole