Minimising greenhouse gas emissions by importing super-frozen tuna

The Fish Society, an online retailer of frozen seafood products, imports super-frozen tuna products. Super-frozen tuna can be transported by sea rather than air freight, which has a lower carbon footprint.  

Seafood is a globally traded commodity; from Barents Sea cod to Indian Ocean tuna, British consumers enjoy access to a huge range of seafood products from around the globe. Transporting products over long distances is often associated with a high carbon footprint, however the way products are transported can have a significant impact on greenhouse gas emissions.   

The Fish Society, an online frozen seafood retailer, imports super-frozen tuna products which are transported by sea rather than air freight, which has a lower carbon footprint.  

Food miles and the seafood trade 

The concept of ‘food miles’ was first raised in the early 1990’s, and the distance over which food products travel from production to the final consumer is still an important factor in assessing the carbon footprint of a supply chain. However, the way in which food products are transported can have a significant impact on the amount of greenhouse gases emitted during transport.  

Tuna is one of the UK’s most popular seafood products and is widely imported in a range of different formats from canned fish to high-end fresh products. In 2020 over 105,000 tonnes of tuna worth £220 million was imported into the UK, with the bulk of these imports coming from countries in the tropics including Ecuador, Seychelles, and Mauritius.1  

Given the long distances that fresh tuna products travel they are often transported by air freight to minimise the time between capture and consumption to ensure that customers receive the freshest product possible. However, transport by air freight is often associated with a high carbon footprint.  

The Fish Society and super-frozen tuna 

The Fish Society is a UK-based online retailer specialising in delivering high quality frozen seafood direct to consumers around the country. The Fish Society stocks a huge range of seafood products and now offers buyers super-frozen tuna. Super-frozen tuna is chilled down to -60°C immediately after capture, this means the product is very high quality and, crucially, products can be exported by sea rather than air freight.  

“We have sold tuna for over 25 years and quickly realised that customers wanted top-quality, fresh sashimi products,” explains Alistair Blair, Chairman of The Fish Society, “Originally we imported tuna loins by air freight and processed them in-house at The Fish Society, however this business is all about making sure the customer is happy and we wanted to trial different products.” 

“We now import super-frozen saku blocks [portioned fish fillets] of tuna which are ready to eat as soon as they are defrosted. When the fish is defrosted it is as fresh as when it was first caught which is perfect for the sushi and sashimi market. It keeps its fresh red colour and doesn’t brown like traditionally frozen products which are chilled to around -20°C. As a result it has been a huge hit with our customers” 

Transporting seafood long distances by sea rather than air can reduce the carbon footprint of the product by as much as 50%. When the fish is stored at -60°C the time between capture and consumption becomes less important as the product is so well preserved.  

“We invested in a bank of five specialised freezers which can chill products to -60°C,” says Alistair, “This means our frozen products are kept at the right temperature at all times from delivery to dispatch.” 

The Fish Society now dispatches over 1,000 seafood orders per week to customers all over the UK.  

Examples like the import of super-frozen tuna show that exploring different product formats can help businesses offer their customers the best possible products whilst also helping reduce carbon emissions. Action across the seafood supply chain, from capture or aquaculture all the way to the consumer, can help contribute to building on the seafood’s reputation as a low impact source of nutritious food.