Category: Fish Cleaning Filleting

Skeletal Anatomy, Knife Blade Flex & Boneless Fillet Butchery

Efficient fish filleting requires understanding teleost fish skeletal anatomy. The spine consists of central vertebrae with dorsal neural spines projecting upward and ventral hemal spines projecting downward, flanked by curved peritoneal rib bones protecting the viscera. A high-quality flexible fillet knife (6 to 8 inches in length, high-carbon stainless steel with a razor-sharp 15-degree edge) allows the blade to bend and contour smoothly along the bony spine without cutting through hard bone or leaving edible meat behind.

The standard 4-step filleting procedure: 1) Make a 45-degree angle incision behind the pectoral fin and operculum down to the backbone; 2) Turn the blade flat and glide smoothly along the top of the dorsal spines toward the tail, stopping just before the tail fin; 3) Flip the fillet over flat on the board and slide the blade between skin and meat, holding the tail tab firmly with a paper towel or fish gripper; 4) Use the knife tip to follow the contour of the rib bones to carve them out cleanly. Finally, ‘zipper’ the fillet by slicing down both sides of the dark red lateral line, producing two completely boneless, sweet white meat loins.