Each year on Earth Day, we are encouraged to take a moment to think about the impact we have on the environment, and how we may act to lessen this. This sentiment is exactly what motivates a group of Faculty of Science researchers at the University of Ottawa, and their partners at Dairy Distillery, as they seek to convert a waste product generated during alcohol fermentation into a novel, green, fertilizer.
Founded in 2018, Dairy Distillery is an innovative company based in Almonte, Ontario, that converts the waste products generated by the milk industry – a sugar-rich liquid referred to as ‘milk permeate’ – into high quality alcohol that may then be used to make vodka (“Vodkow”) and other spirits. More recently in response to the COVID-19 pandemic, Dairy Distillery received funding from the Ontario Together Fund to expand into the production of hand sanitizers. With this funding, they have been able to scale up production to more than 230,000L of ethanol for hand sanitizers, redirecting 2 million liters of milk permeate from waste into a product that helps stop the spread of COVID-19.
With every success comes new challenges however, and with the scale at which Dairy Distillery plans to be producing alcohol in the future, more waste, known as stillage, will be produced. “Stillage is the material leftover at the end of the fermentation,” says David Geros, CTO at Dairy Distillery since 2019. “It’s like the waste of the waste”. Nevertheless, stillage is rich in organic matter, including compounds high in phosphorous, nitrogen, and potassium, making it a likely candidate for use as a fertilizer to enhance plant growth. “We will need to find a new home for our stillage as the company continues to grow and large-scale low carbon fuel ethanol plants come online. Conventional wastewater treatment can be used, but at large scale, it would be expensive and the fertilizer components would be disposed of. It would be ideal if we could close the loop by having nutrients in the fermentation waste being used to help grow crops for dairy cows and human food crops.”
“My lab was approached by the Dairy Distillery team to see whether we would be interested in trying it out as a potential fertilizer” said Dr. Allyson MacLean, an assistant professor at the University of Ottawa. “To me, the benefit in doing so seemed obvious. The question however was ‘will this work’?” The MacLean lab partnered with a research lab lead by Dr. Alexandre Poulain, a full professor at uOttawa and Associate Vice-Dean of Innovation & Strategic Partnerships. Together, they developed a research plan to explore the potential of stillage to act as a fertilizer, a project jointly funded by the Faculty of Science, Dairy Distillery, the NSERC Alliance program, and the Government of Ontario through the Ontario Centre of Innovation. “As an environmental scientist and microbiologist, it is very inspiring to support Dairy Distillery, not only to help them produce Vodkow, but also to find a sustainable solution to their waste problem. It offers a holistic view of environmental issues and greatly contributes to the student experience,” said Dr. Poulain. In addition to benefiting Canadians, this project directly addresses seven of 17 United Nations Sustainable Development goals associated with clean water, energy and environmental sustainability.
“Since I’ve been with this project from the beginning, I am looking forward to once again transform a waste product into something that can be useful and help lower the amount of environmental waste produced. The partnership between Dairy Distillery and the University has helped make a product that has been profitable for the company while also giving a student experience in how to apply lab work and adapt it for industrial scale as well as how to communicate science to an industry partner” added Jessica Gaudet, a graduate student jointly supervised by Drs. MacLean and Poulain.
The project is still at an early stage, but preliminary results suggest that diluted stillage may indeed have potential as a fertilizer, following a trial run on edible crops such as peppers, tomatoes, cucumbers and corn.
“I think it's important for companies such as Dairy Distillery to invest in research because it can help their bottom line in addition to helping the environment. I foresee a change in the culture surrounding waste and hope that a multitude of waste products are further researched to determine how they could be re-used rather than disposed of” said Mina Nasr-Sharif, a lab technician who is helping on the project.