The university aims to address concerns over the accumulation of toxic mercury, citing the World Health Organisation (WHO)’s warnings that mercury is one of the ten most harmful chemicals for humans. WHO says that exposure can damage the central nervous system, with foetuses and young children being particularly sensitive to the effects.
In a previous study, the researchers investigated the possibility of coating packages with thiolated silica to capture mercury from canned fish. They observed that the forces binding the mercury within the tuna tissue prevented it from being released. Apparently, proteins in tuna tissues, particularly sulfur-containing amino acids, strongly bind and accumulate mercury due to the strong interactions involving thiol groups from these amino acids.
“By knowing that, we decided to add one of them, cysteine, to a water solution in which fish meat can be immersed. We believed this would allow some of the mercury to be drawn out and instead bind to the solution and be discarded. Further research is needed to take care of the removed mercury,” says Przemysław Strachowski, first author, and (at the time of study) a postdoc at the Department of Life Sciences at Chalmers.
In the study, the researchers discovered that the greater the surface area of fish flesh in contact with the cysteine solution, the higher the mercury uptake. The highest value of mercury reduction, 35%, was reached when testing canned minced tuna from regular grocery stores. They also discovered a maximum threshold of two weeks, after which no further changes occurred. Cell-based assays have reportedly proven the safety of the developed technology.
“The beauty of this type of packaging is that it is active while the product is on the shelf. No additional production steps would be needed if a method like this were used industrially. The application of our results could increase the safety margin for fish consumption,” says Strachowski.
In related news, Aptar Food Protection developed the SeaWell active packaging solution for seafood last year, designed to help maintain freshness, quality and aesthetics. Utilized by retailers across the U.S, the packaging technology aimed to reduce the rate of seafood microbial growth, chemical degradation and odour accumulation.
At the end of 2024, DS Smith developed a fibre-based pallet solution for Danish seafood producer Vilsund Blue A/S, replacing plastic pallets for canned products. The corrugated cardboard packaging sought to eliminate plastic use and increase the number of cans per pallet.
