Startup makes eco-friendly packaging with onion skin

A range of new eco-friendly packaging materials made from onion skins and peelings is being created by an Oban-based startup, offering an alternative to fossil fuel-derived plastic products – a major contributor to household waste.

HUID workers holding onions for its onion skin plastic product

Founded by textiles specialist Renuka Ramanujam, HUID recently moved into a new lab and office space to advance its compostable packaging concept. The team is being supported by the National Manufacturing Institute Scotland (NMIS), operated by the University of Strathclyde and part of the High Value Manufacturing (HVM) Catapult, while the Advanced Materials Research Laboratory (AMRL) at the University of Strathclyde is undertaking rigorous testing of the onion-based materials.

HUID translates to ‘skin’ in Dutch, which is founder Renuka’s second language, while ‘ui’ is also the Dutch word for onion. The business has so far created two prototypes – a cardboard-like material, Pyber, and a flexible film equivalent, Cellofil – with AMRL’s mechanical tests and NMIS’ lifecycle assessment confirming their performance, functionality and environmental footprint. 

Producing the packaging involves extracting high-quality cellulose from onion skins and combining it in a biopolymer blend, creating a film with a mechanical strength comparable to conventional plastics. Onion skins also have anti-microbial properties, meaning the packaging could help extend the shelf life of perishable foods.

Following the appointment of a chief scientific officer, HUID is preparing to launch Pyber as its first product by the middle of next year. The startup recently secured £150,000 in funding from Innovate UK to improve its processing methods and manufacturing as well as £20,000 from The Greenhouse – a climate tech accelerator programme part of The Grantham Institute and Imperial College London. 

Up to 400kg of waste onion skins are produced per week, with the majority ground up for use as cattle feed, while UK households throw away an estimated 90 billion pieces of plastic packaging annually

Renuka Ramanujam, HUID’s founder, said: “Onion skins are nature’s own form of packaging, protecting the onion below from harm and are a plentiful waste source. Yet, after speaking to various scientists I realised that no one was using them as a material and spotted a gap in the market for a new variety of eco-friendly packaging. 

“Working with NMIS and the AMRL has been instrumental in refining our products and gaining the validation we need to show buyers and consumers that the compostable packaging meets the same standards they might expect from single-use plastic or cardboard.

“Scotland boasts an excellent startup community with universities and other networks like Scottish EDGE and IBioIC providing businesses with crucial support in their early stages. They’ve not only helped me access expertise and funding but have also connected me with key industry partners and a talented pool of interns and potential employees eager to get involved with HUID and sustainable biotechnology.”

Aineias Karkasinas, Sustainability Engineer at NMIS, said: “Our collaboration with HUID perfectly illustrates where NMIS can add value by helping transform manufacturing practices.  NMIS champions sustainable solutions and supports small and medium sized businesses through providing them with access to expertise and equipment they may not have in-house.

“HUID’s creative use of onion skins minimises waste and is a great response to the current market need for sustainable packaging. It has been great to support the development of genuinely sustainable solutions and provide HUID with deeper insights into the environmental performance of its materials.”

Dr Tiziana Marrocco, Knowledge Exchange Manager at AMRL, added: “We have been working closely with HUID for over two years, supporting its product development with consultancy in materials properties and performance. It is so rewarding to see how far the business has grown since the early steps and knowing that our collaboration carries such a relevant societal message.”