Handling Trout with Care: An Innovative Project for Animal Welfare
When it comes to trout farming, we often think first of the quality of the final product or compliance with health regulations. But how often do we stop to think about how animals experience the final moments of their lives?
The Friuli agri-food centre, together with the company Friultrota, wanted to turn this mindset on its head by contacting us with a truly revolutionary project: they wanted to ensure a more ethical slaughtering method, one that could minimise stress for the trout and optimise their welfare.
An “ethical” slaughtering procedure
The centre had already conducted studies on the different slaughtering techniques, discovering that animal welfare could be measured using an enzyme found in the blood of fish. More traditional methods, such as the blow to the head, yielded good results from the point of view of “speed” but did not always guarantee the highest standards of respect for the animal. This is why the idea of a “cold-induced asphyxiation” was considered, considering that trout can withstand temperatures as low as around -8 °C.
How do you reach -10°C?
This is where our experience comes into play. We had to design a system that would bring the water to a temperature of about -10°C, without freezing it. The basic idea? A salt-water tank (to lower the freezing point), combined with a eutectic system capable of reaching -16°C.
But there was one important detail to consider: the water had to remain in a liquid state to allow the trout to swim, while being cold enough to induce a quick and painless “sleep”. In essence, we created a delicate balance between temperature, salinity and water recirculation, making sure that the fish didn’t experience a traumatic shock.
The second challenge: a tank built for…600 trout!
Keeping the water at -10° C was already a significant achievement, but the real hurdle came when the customer told us that they needed to process up to 600 kilograms of fish at a time. Imagine: hundreds of trout swimming together, raising the water temperature through body heat – and in no time, risking a loss in cooling efficiency. The tank also had to hold up to 6,000 kilograms of fish and water – a real structural challenge!
To solve these problems, we engineered a reinforced structure, using materials suitable for supporting heavy loads without warping. In addition, we included special heat exchangers and a particularly powerful eutectic system capable of restoring the required temperature even after large batches of fish were introduced.
An experiment in its own right
Creating such a system on a large scale was, in every sense, an experiment. It was an experience halfway between science and engineering, involving tests and simulations to fine-tune every detail: from salt concentration, to the positioning of temperature sensors, to the monitoring of trout welfare.
Each step was discussed with the specialists of the centre who, through blood analysis, confirmed significantly lower stress levels achieved with this slaughtering method.
The results: animal welfare and customer satisfaction
In the end, the system worked flawlessly: the trout, placed in this “super-chilled” water, entered a kind of dormant state before gradually dying and, according to the analyses, without peaks of stress. The customer, delighted to have found a more ethical solution, was able to confirm that the final product was of high quality, with a fresh, firm meat.
Looking to the future
This project is a striking example of how innovation and research can improve not only product quality, but also respect for animal welfare. More and more companies and research centres are showing interest in solutions that combine efficiency and compassion. And we’re ready for the next challenge, confident that cold chain technology can be applied in unexpected sectors.
Whether it’s “just” trout or other animals, we believe that the desire to do better – for nature and for people – is the true driver of innovation. There’s still so much to learn, but this experience has taught us never to stop experimenting and exploring new paths.
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Want to discover more stories where the animal world meets innovation in refrigeration? Check out our equally fascinating project involving some animals that are a bit more… furry!
Read the full article now on our blog (link coming soon).
