Salt cod inspires possible method to preserve tissue
Consider the humble cod. For centuries one of the most soughtafter North Atlantic fish for tables on both sides of the ocean, cod is central to a wide array of comforting dishes. Now dried salt cod figures in studies by researchers at the Norwegian University of Science and Technology in Trondheim as they look for ways to better preserve human tissue.
Tissue samples are now preserved through freezing, either in formalin or liquid nitrogen, and stored at temperatures from 112 to 315 degrees below zero. But keeping tissue at such low temperatures is expensive and requires close monitoring. Cue the cod. The Nordic scientists are looking at one method that uses rapid freezing along with a longtime Norwegian method to dry salt cod.
Drying would be a big money-saver, and the tissue could be stored at higher temperatures in ordinary freezers or refrigerators.
“A method that would allow samples to be dried is therefore of great interest to areas of the world with limited economic resources,” said Professor Jostein Halgunset.
In the method under study, tissue from test animals was rapidly frozen in liquid nitrogen, than dried with a heat pump at temperatures from 14 to 41 degrees, much like the method used to dry salt cod. The results: RNA and cell structure was mostly preserved, making the method promising and cost-effective.
The team recently published its findings in the journal Drying Technologies.
Traditionally salt cod is hung up to dry in Norway.