Scottish scientists turn cheese byproduct into fuel

Scottish researchers have teamed up with an agricultural company to explore new ways of turning a cheese byproduct into fuel.

Researchers at Heriot-Watt University worked with Take Root Bio to successfully turn salty whey – a difficult, high-volume by-product from cheese production – into a widely used fuel called bioethanol.

The process could be used to tackle one of the dairy industry’s biggest waste challenges.

“We’ve always been interested in what happens when you stop looking at something as waste and start asking what else it could become,” Kirk Siderman-Wolter, founder of Take Root Bio, said.

“The company began by looking at how people might grow food in space, where every resource matters and nothing can be thrown away.

“The same principles apply surprisingly well here on Earth.”

He added: “Salty whey is produced in huge volumes and can be difficult to deal with, so we wanted to find out whether there was a better use for it.

“If we can help turn something that currently costs money to manage into something with real value, that’s a positive outcome for both dairy producers and the environment.”

The challenge of disposing of salty whey is significant. About 95,000 tonnes of the substance is generated in the UK each year from production of cheddar and similar cheeses, and its combination of milk sugars and high salt content makes management particularly difficult.

A single dairy producer can generate tens of thousands of litres every week, creating both environmental and economic pressures for the sector.

At the heart of the project was the idea that salty whey could be treated as a resource rather than waste, meaning dairy producers could potentially reduce the costs associated with its management while providing feedstock for new bio-based products.

Researchers from Heriot-Watt University and Take Root Bio, supported by the Industrial Biotechnology Innovation Centre (IBioIC), looked at how the sugars found in salty whey could be transformed through a bio-based process, creating value from a material that is often difficult and costly to manage.

“One of the biggest opportunities in industrial biotechnology is finding new uses for materials that are currently treated as waste,” Dr Liz Fletcher, director of impact and deputy chief executive at IBioIC, said.

“By bringing together businesses and academic expertise, projects like this can uncover solutions that deliver both environmental and commercial benefits.

She added: “What we liked about this project was that it approached a familiar problem from a different angle. That’s exactly the sort of innovation we want to support, and we’re excited to see where the work goes next.”

The process also leaves behind a secondary stream that could potentially be recovered and reused.

Researchers are also looking at whether mobile production units could be deployed closer to where these by-products are produced, helping to reduce transport requirements and making the concept easier to scale.

“Food and drink manufacturing produces a huge range of by-products, many of which still contain valuable components but can be challenging to manage,” Dr Jane White, an expert in waste valorisation at Heriot-Watt University, said.

“That makes them interesting candidates for bio-based processes that can recover value from materials that might otherwise be treated as waste.”

Take Root Bio is also exploring ways to capture gases generated during fermentation, such as methane and hydrogen, for use in future food production systems.