King Threadfin
Polydactylus macrochir
Other Names
Burnett’s salmon, king salmon, threadfin, threadfin salmon.
Family
Polynemidae (threadfin salmons).
Description, Location, Habitat and Harvesting Information
Available wild-caught, it is a bottom-dwelling fish with elongated body and 4-5 filaments below the side fin, which it uses to detect food, such as small crabs, prawns and worms in the mud. Found mostly in very shallow water along the coast, in muddy bays, estuaries and rivers of tropical Australia from Fraser Island to west of Darwin and occasionally in freshwater. Caught mainly by gillnets in the Gulf of Carpentaria, it is an important bycatch of Barramundi fishing.
Season
Available year round with limited supplies from November to January.
Size and Weight
Commonly 1.5-6kg and 50-90cm, but can grow to 30kg and 185cm.
Price
High priced.
Relations
Blue Threadfin (smaller with fewer filaments below the side fin).
To Buy
Sold mostly whole (gilled and gutted) or in skinned fillet or cutlet form, though sometimes seen as headless trunks or steaks. It often has large bony growths along the backbone, which make it difficult to fillet, so it is best cut into cutlets or steaks or bought already filleted. In whole fish look for lustrous skin, firm flesh, and a pleasant, fresh sea smell. In cutlets, steaks and fillets, look for white-pale pink, firm, lustrous, moist flesh without any brown markings or oozing water and with a pleasant fresh sea smell.
To Store
Make sure whole fish is scaled, gutted and cleaned thoroughly. Wrap whole fish, fillets, cutlets and steaks in plastic wrap or place in an airtight container. Refrigerate for up to 3 days or freeze whole fish for up to 6 months, and fillets, cutlets, trunks or steaks for up to 3 months, below -18ºC.
To Cook
Average yield is 55%. Has a medium flavour, low oiliness and moist, firm flesh with large flakes and bones that are easily removed. The centre bone of cutlets can be removed and a filling placed in the cavity. Cut thick fillets into serving-size portions and score to allow even heat penetration.
Cooking Methods
Deep-fry, pan-fry, stir-fry, bake, grill, barbecue. The firm flesh holds together well in soups, curries and casseroles and can be cubed for kebabs.
Goes Well With
Asian greens, butter, chilli, citrus, herbs (such as chives, French tarragon, parsley), soy sauce, tomatoes, white wine. Good barbecued or baked wrapped in paperbark or banana leaves.
Alternatives
Barramundi, Morwong, Silver Perch, Yellowfin Bream.
Imports
Frozen fillets of various Threadfin species are imported from Namibia and Asia (notably Taiwan), and sometimes mislabelled as King Threadfin. True King Threadfin only occurs off northern Australia and southern New Guinea.
Recipes