Kelpi Seaweed-Based Barrier Coating

Kelpi is a UK materials company founded in Bath in 2020 and now based in Bristol, created to replace fossil-fuel plastic in packaging with seaweed-derived alternatives. It targets plastic-lined paper and fibre packaging, which is hard to recycle and adds to plastic pollution.

Kelpi functionalises the natural carbohydrates in farmed seaweed, combined with vegetable oils, into an ultra-thin barrier coating of about 0.01 mm for paper, card and fibre. The coating is heat sealable, resists grease and acidic contents, reaches a water vapour transmission rate below 2 g/m2/day and an oxygen transmission rate of 6 cm3/m2/day, and lets coated paper go into the standard paper recycling stream. It is aimed at food and drink, personal care and home care packaging, with brands such as Homethings and Bower Collective and packaging group Amcor among its partners.

• Seaweed chemistry: functionalised seaweed carbohydrates combined with vegetable oils.
• Ultra-thin layer: coating thickness of about 0.01 mm on paper, card and fibre.
• Moisture and oxygen barrier: WVTR below 2 g/m2/day and OTR of 6 cm3/m2/day.
• Heat sealable: compatible with industrial processing for sachets and pouches.
• Paper-stream recycling: coated material is accepted in standard paper recycling.
• Co-development: R&D contracts with brands and packaging converters for specific formats.

• Vietnamese paper packaging converters offering plastic-free coated paper for snacks, coffee and confectionery.
• Food and FMCG brands replacing plastic sachets for sauces, seasonings or refills with recyclable paper sachets.
• Exporters preparing for EPR requirements in Vietnam and in EU markets.

• Plastic-free barrier: replaces fossil-based plastic linings with a 100% bio-based seaweed coating.
• Recyclable packaging: coated paper and card go into the standard paper recycling stream without separation.
• Functional performance: grease, acid and moisture resistance with heat sealability for sachets and food packs.
• Food-contact clearance: the coating has completed the US FDA food contact notification process.

Extended producer responsibility rules and brand commitments are pushing food and FMCG companies away from plastic-lined packaging toward recyclable paper formats. Southeast Asia is a major seaweed producer and a growing paper packaging hub, which makes seaweed-based coatings relevant for regional converters and exporters.

Founded in Bath, UK, in 2020 by three founders; moved to Bristol in 2022. Raised pre-seed (2021), seed (2022) and seed 2 (2024) funding. Certified B Corporation since 2023. Gold winner in the Sustainability Start-Up category of the Sustainable Food Awards 2026; CEO Hugo Adams named to the 2026 Meaningful Business 100.