The fish is hooked, plucked from the ocean, and with saltwater still dripping from its fin, frozen.
Contact freezing involves sandwiching the fish between refrigerated plates attached to hydraulic rams.
"This freezes the fish, literally moments after being caught. . . . brought down to a temperature of minus-40 degrees Celsius," says Zachary Semeniuk, president of Wild Ocean Fish.
Fish aficionados should be aware of the increasing number of hook-and-line vessels using contact freezers, according to Semeniuk.
"You seal in all the flavour, the texture, the nutrients are all there, and that's really changed the game in terms of having an experience where frozen is now truly fresher than fresh."
While some chefs recoil at the thought of lean, frozen, fish, Semeniuk says damage to the texture of lean fish only occurs with a slow freezing process.
"Lean fish can be problematic if they're frozen very slowly at relatively warm temperatures," he says. "The water freezes in very large, well-developed crystals, and that actually can damage the flesh a little bit, and that's when you start losing texture. When you flash freeze. . . . You don't have the tearing and ripping."
Whether the dish is coho salmon or albacore tuna, flash freezing locks in the best flavour, according to Semeniuk.
"Truly fresh fish should have a clean, saltwater flavour, and that's what frozen at sea fish tastes like."
While the practice of flash-freezing fish is on the upswing, many vendors are reluctant to disclose it to their customers, according to Semeniuk.
"It hasn't really been used as a marketing tool. Some smaller fish shops will sometimes advertise some of their premium items as frozen at sea, but for the most part, consumers are unaware of when they're purchasing frozen at sea fish."
