The ULT (Ultra Low Temperature) Process
Did you know that 80% of the sashimi grade tuna consumed in Japan has been previously frozen using ULT technology?

It’s true! For centuries, Japanese fisherman have fed the insatiable appetite of their homeland by fishing locally and bringing home the tuna within a few days of catch. But as time progressed and consumption continued to rise, the fisherman have had to travel longer and longer distances to harvest this prized specie.

To maintain the sashimi quality of the fish on these longer trips, a new type of super-freezer was introduced.   Regular freezers, which only provide temperatures to 0° F, were found to be insufficient in locking in the “just caught” characteristics of tuna and ultimately were not a good solution. Japanese engineers developed a new type of “super” freezer that holds a temperature of -76° F. At this low temperature, the deterioration of tuna or any fish caught would stop instantaneously, thus preserving the catch for longer periods of time.

The entire Transmarina fleet is outfitted with these high-technology ULT freezers.

Once the tuna is harvested live from the ocean, they are immediately bled, gutted, and graded on board the vessel. They are then quickly whisked into the onboard ULT freezers where they are frozen to a core temperature of -76° F, generally four hours after catch.

The tuna remains at -76°F through the entire processing and shipping process. Once offloaded from the vessels, the tuna is graded again and then processed into loins, portions, steaks, saku blocks or cubes. Tristan has the capability to customize cuts specific to customer needs.

For the US, the product is loaded onto specially constructed ULT shipping containers to travel to Tristan’s US corporate facility in Dania Beach, Florida. Tristan employs rigorous quality-control standards and the product remains at -76°F all the way to customer’s kitchens across the United States.

Once the tuna is properly re-freshed, it blooms its authentic ruby red color and delivers an exceptional eating experience–like it was just caught!