24 Agosto 2021

Clean waters for Scottish salmon

The University of Trento, with Francesco Parrino and Annachiara Berardinelli, in partnership with Hub Innovazione Trentino, is conducting research on a water purification technique within an EIT Food project in the "Sustainable Aquaculture" area

An innovative water purification system is about to become operational in Dunkeld, Scotland. It will be used to keep the tanks clean at an international salmon farming company. The system was developed by the University of Trento and is based on the ability of light to destroy pollutants and toxic substances that form in the breeding water. In this way, salmon will continue to swim and grow in a clean and healthy environment for their well-being and that of consumers. 
At an organizational level, the research group is coordinated by HIT HUB Innovazione Trentino, that will also promote the results of the project as a catalyst for innovation and technology transfer at the local level.
The low cost and low impact technology that uses light and ozone (photocatalytic ozonation) to purify water was developed by Francesco Parrino, researcher of the Department of Industrial Engineering.
Parrino has been studying photocatalysis since his master's dissertation, in 2005, when he graduated from the University of Palermo, and has proposed innovative applications for the industrial sectors since he earned his doctorate from the Friedrich-Alexander University of Erlangen - Nuremberg (Germany). He has been a researcher at the University of Trento since 2018.
The advantages of photocatalysis for sustainable aquaculture were also the focus of an article, "Photocatalytic ozonation for a sustainable aquaculture: A long-term test in a seawater aquarium", that was recently published in the journal "Applied Catalysis B: Environmental" (doi:
Francesco Parrino is one of the authors of the all-Italian study, conducted with Giovanni Camera-Roda (University of Bologna), Vittorio Loddo and Leonardo Palmisano (University of Palermo).
The key to our work - Parrino explains - is the ability of light to activate a semiconductor which in turn triggers a series of radical reactions that lead not only to the complete degradation of pollutants but also to the removal of pathogens such as viruses and bacteria. Our study - he underlines - shows that the photocatalytic ozonation system for water purification is an excellent ally for developing sustainable land-based aquaculture, in recirculating systems. In this way, we protect inland and marine ecosystems which are currently threatened by intensive farming that have a high environmental impact and make extensive use of antibiotics. 
With these systems, the well-being of the fish can significantly improve, as well as the nutritional and organoleptic quality of the product. The research group led by Annachiara Berardinelli, a researcher who works both at the Center for Agriculture, Food and Environment and at the Department of Industrial Engineering, will focus on this aspect, but will also try to develop fast and non-destructive sensors for the real-time evaluation of fish welfare and the estimation of the main quality indices of the product.
As the project evolves, it will also take into account the final stage of the process, when the product hits the shelf: the behavior of consumers, their awareness in making responsible choices for the environment and health, will be studied by Francesca Forno's research group at the Department of Sociology and Social Research.
The project also includes a group led by Prof. Alessio Bonaldo at the University of Bologna, which will be responsible for applying photocatalytic ozonation technology on sea bream and bass. 
Parrino says: "We will first implement the system in Scotland. FishFrom Ltd enthusiastically welcomed our proposal because it is a company that has long been using innovative technologies to minimize environmental impact and increase animal welfare. We are working together to install our prototype in their production system".
The development of sustainable aquaculture requires new-concept models for water replacement and purification (recirculating aquaculture systems, RAS).
He stresses: "The consumption of marine fish resources is such that Europe is investing a lot in the development of aquaculture. In the next 15 years, the demand for farmed fish products is expected to grow enormously and therefore we must improve our production system to protect humankind and the environment. The technology developed by the University of Trento helps sustainable fish production because it reduces costs and increases food safety. Our study has also shown that the technology developed does not alter and indeed improves water quality parameters".
One of the questions that Parrino and Berardinelli might be asked is why a research project of UniTrento focused on Scottish salmon and not on a native salmonid, such as trout or char.
Parrino explains: "We believe that the fish farming industry in Trentino will follow closely the developments of the research work we are doing on the production of salmon, which currently is the most important commercial sector globally. The results of our work will also be extremely important for the businesses operating in our region".
Berardinelli adds: "All the sensors developed during the project will certainly have a positive impact on Trentino aquaculture and will be a driving force for its international expansion".