In Hawaiʻi’s seafood industry, food preservation is a high priority. Fresh fish in particular, is prized and incorporated into popular local and ethnic dishes, such as poke and sushi, and more fish is consumed here per capita than on the mainland.
For an industry whose businesses rely on new and better ways to preserve the quality and economic value of their product over an extended period of time, researchers Soojin Jun, Kacie Ho and Yong Li of the University of Hawaiʻi at Mānoa’s College of Tropical Agriculture and Human Resources Department of Human Nutrition, Food and Animal Sciences may have a solution. They have developed a proprietary supercooling technology that can preserve perishable materials at below-freezing temperatures, without the formation of ice crystals.
“We have been testing the supercooling process on a fresh yellowfin tuna (ʻahi) fillet, and so far, the fish has been preserved for 10 days without any deterioration or compromise in quality,” said Jun.
The researchers have procured a Novel Food and Innovative Manufacturing Technologies grant from the U.S. Department of Agriculture-National Institute of Food and Agriculture to develop and validate their technology, which utilizes electric and magnetic fields. They also hope to prove the system can be scaled-up to a larger storing dimension, and keep food materials fresh in a supercooled state throughout the food supply chain (from production to consumption) to maximize their economic value.
“Freshly caught fish is generally put on ice while at sea, and must be consumed immediately, or preserved in order to reduce the risk of spoilage,” said Jun. “Frozen fish can be stored longer, but texture and overall quality is diminished by the freezing/thawing processes. Supercooling involves chilling of fish below a phase transition temperature in a balanced state, leading to prevention of their cellular activity.”
He added, “This has the potential to be a radically new food preservation method for consumers and the commercial food industries. Food could be maintained in their natural state with the same taste, texture, nutrition and moisture content they had before being supercooled.”