How the Scottish whisky industry is inadvertently tackling overfishing

Douglas Martin has always loved the ocean.

“I’ve always felt some connection to the ocean, and water in general. I always feel more at home when I can hear the waves crashing – finding silence amongst the noise,” he says.

While Martin was raised in South Africa, his parents are Scottish, and he says he “was very much raised as a Scot”. 

“The wonderful thing about living in Scotland is that all the main cities are very close to nature, so the oceans and rivers are right there for us all to enjoy.” 

It’s perhaps this appreciation for the seas that gave Martin his ‘aha moment’: to create a sustainable alternative to Omega-3 supplements for humans and farmed fish that doesn’t rely on wild fish while at the same time cleaning up a problem within Scotland’s most popular global industry, whisky. 

Because why solve one climate challenge when you can fix two?

Overfishing is being caused by a global need for Omega-3

Omega-3 is an essential nutrient. For humans, these fatty acids allow cells to function properly and are vital for brain function, eye health, and heart health. It’s also been thought to be good for lowering anxiety, reducing joint inflammation in rheumatoid diseases, and preventing dementia. 

Unfortunately, human bodies can’t produce Omega-3 on their own, which is why 16 million fish are caught every year – to help us with our nutritional needs. Of all those wild-caught fish, 20 per cent of them are used to feed farmed fish. 

What’s more, our global appetite for fishmeal and fish oil is growing, with demand for small fish expected to exceed supply by 2037 – just 12 years away.

As 90 per cent of wild fish can be eaten by people, Martin quickly realised it made no sense to catch wild fish solely for supplying Omega-3, as this then puts the food security of coastal communities under threat. 

So, while studying at the University of Edinburgh, Martin decided to look for an alternative – and MiAlgae was born in 2016.

Scotland’s whisky industry causes wastewater

Scotland’s whisky trade is vital to the UK economy, creating 66,000 jobs and bringing in £7.1 billion (€8.5 billion) to the British economy, according to the Scotch Whisky Association. 

But how does that connect with Omega-3 and the sea? Well, for every litre of whisky produced, there are approximately 15 litres of byproducts, which are discharged into the sewage system or rivers after treatment. 

“A lot of people believe that fish produce Omega-3s, and that’s simply not true,” explains Martin. “They accumulate them from the algae they eat.” 

“When I learned that fact and realised that farmers, to get the fish the nutrients they need, are forced to use wild-caught fish as the source of Omega-3s for their farmed fish, it seemed obvious that there needs to be a limit to that,” he says. 

“Then I thought that perhaps we could solve two problems – the issue of overfishing and also trying to keep wastewater out of the oceans by using whisky byproducts as feedstock.”   

Around 1 million litres of wastewater is produced every year from the whisky distilling process in Scotland – and globally, it’s estimated that the Scotch whisky industry procures as much as 2.6 billion litres each year.

“The whisky industry in Scotland is one that produces a lot of surplus byproducts that, lucky for us, is rich in all the lovely nutrients that our algae love to eat, so it was a bit of a no-brainer!” says Martin.

 Martin and his team located their hub close to multiple sources of waste distillery water and use renewable energy to run huge 30,000-litre fermenters that produce tonnes of algae every week. The algae is then dried and turned into a powder that can be used as aquafeed (for the farmed fish) and also in pet food.

An algae production that reduces carbon emissions, twice over

Martin asserts that while the process sounds really simple, it has taken “some years to perfect”. He also had support from his co-inventors Shreekanth Ramananthan and Julian Pietrzyk. Undoubtedly, his Master of Science in synthetic biology and biotechnology would have helped too. 

“One of the great things about it though is the circularity,” Martin adds. “Using the waste products from one industry to produce a valuable product for another is one thing, but I also love the story that by using microalgae grown in the byproducts of whisky to feed farmed fish (salmon) it helps two of Scotland’s biggest exports to thrive in a more sustainable way!”

Just one tonne of MiAlgae’s patented algae can create as much Omega-3 as 620,00 fish and can save nearly 40,000 kg of CO2 by reducing fishing to produce fishmeal. 

And how much wastewater are they able to recycle? The team estimates that in 2024, it was enough to fill almost 300 Olympic-sized swimming pools, preventing the release of 150,000 kg of CO2 – the equivalent of 500 round-trip flights between Edinburgh and London.

After being an Earthshot finalist, MiAlgae is ramping up operations

While other algae production methods are out there, MiAlgae claims that their solution is more scalable and cost-effective. And, because they use fermentation tanks very similar to those used in brewing, the potential is there to adapt them to other waste nutrient sources, too.

“We’re now at the point of making commercial quantities and will soon be moving to a new purpose-built site where we can roll out higher amounts to our customers,” adds Martin. 

MiAlgae was propelled into the limelight late last year when it was shortlisted for the Revive Our Oceans Earthshot Prize 2024, the global environmental award that was launched by The Royal Foundation and Prince William, Prince of Wales, in 2021.

“Being selected as an Earthshot finalist has been an incredible honour and a testament to the hard work our team has put into creating a sustainable solution that can truly make a difference for our planet,” says Martin. 

“The Earthshot Prize has helped amplify the urgency of addressing marine ecosystem degradation and gives us a global platform to inspire change. This recognition has fuelled our ambition to scale our solution and lead the way in sustainable food production.”

By being a finalist, not only has the team at MiAgae received visibility and credibility, but it’s also been able to tap into a team of key global players, from investors to policymakers, that will help accelerate the worldwide adoption of the company’s technology.

“In the next five years, we aim to be a global leader in sustainable food production, providing scalable alternatives to fish-based oils,” Martin says. 

“We want to be at the forefront of a movement that not only revives our oceans but also redefines how we produce essential nutrients for a growing population”.