I don't know about you, but I love canned tuna. Convenient, tasty, rich in proteins and essential fatty acids. Of course, the fresh one is much better: and then there is always that annoying thought about mercury that spoils my pleasure. Is it really necessary to limit its consumption to avoid risks? A team of Swedish researchers may have found an extraordinarily simple solution to this dilemma. The cysteine, a natural amino acid, added to the tuna preservation water, It is able to “capture” up to 35% of the mercury present, significantly reducing health risks.
A discovery that could radically change the way we consume this precious food, allowing us to enjoy its benefits with greater peace of mind.
Mercury in Tuna: A Controversial Story
Every time we have addressed the topic of mercury in tuna (spoiler: it's there and it hurts), we have whetted the appetite of hordes of more or less improvised “debunkers”, eager to make visits and profits with pseudo-reassuring posts that however never addressed the merits of the issue. The truth is that mercury is a real problem, so much so that It is recommended pregnant women and young children to limit their consumption of fish such as tuna.
Mercury accumulates in fish tissues through a process called bioaccumulate, with top predators (like tuna) containing the highest concentrations. It binds to proteins in muscle tissue and remains there, ready to be passed on to those who eat it.
By limiting consumption, the nutritional benefits of fish outweigh the potential risks. But finding a way to reduce mercury content without compromising nutritional benefits? This is the Holy Grail of seafood food safety.
Cysteine: An Unexpected Weapon
Why researchers at theSwedish University of Agricultural Sciences and Chalmers University of Technology They focused on cysteine? For one reason: cysteine has a strong affinity for mercury. Ironically, it is precisely this affinity that allows the metal to accumulate in fish in the first place.
We believed that this would allow us to extract some of the mercury, causing it to bind to the solution and then be discarded.
the chemist explains Przemyslaw Strachowski, co-author of the study that I link to you here.
The process is surprisingly simple: soak the tuna in water containing cysteine. The more surface area of the fish that comes into contact with the solution, the more mercury is extracted. Laboratory tests have shown a 25 to 35% reduction in mercury content, without perceptible alterations in the appearance or odor of the fish.
Packaging that works while you wait
The beauty of this technology lies in its simplicity. It does not require additional production steps: decontamination occurs while the product is on the supermarket shelf, continuing for a period of up to two weeks.
For companies, implementing this solution would require minimal changes to existing processes. For consumers, it would mean a greater safety margin without sacrificing the nutritional benefits of tuna.
Cysteine, beyond consumption limits
The food researcher Mehdi Abdullahi underlines a fundamental point:
Our study demonstrates that there are alternative approaches to addressing mercury contamination in tuna, rather than simply limiting consumption.
This represents a major paradigm shift: instead of focusing only on educating consumers about the risks, the industry can actively address the problem at its source.
The road to seeing this technology applied on an industrial scale still requires research, but the direction is promising. We may be one step away from making current warnings about tuna consumption obsolete, for the sake of the "debunkers".
