Handing Spencer Gulf King Prawns
Spencer Gulf King Prawns - Melicertus latisulcatus
Region of origin
Prawn fishing is not permitted within waters less than 10 metres in depth. Whilst the fishing grounds cover a relatively large area of the West Coast and Spencer Gulf, they are adjusted based on survey results and commercial catch statistics.
Some areas have been permanently closed to fishing to protect juvenile prawns, other fish species, high biodiversity areas (including rocky or reef systems). Generally fishing only takes place in areas where catch is known to be located. The main home ports for the fisheries are Port Lincoln, Wallaroo and Venus Bay.
Prawns tend to prefer to live in warmer tropical or sub-tropical water regimes. Spencer Gulf King Prawns are considered to be at the lower limit of temperatures for this specie of prawn, making them unique.
The Spencer Gulf King Prawn Fishery has long recognised the importance of fishing to the highest sustainable standards and has become the first tropical prawn in the Asia Pacific region to be certified sustainable by the Marine Stewardship Council.
The fishery is mandated to maintain ecological sustainable stock levels and minimise impacts on the ecosystem.
Spencer Gulf King Prawns, like other prawns, exist at the bottom of the food chain. They are omnivorous scavengers, feeding on plant material, crustacea and small fish.
Prawn fishing is undertaken using the demersal otter trawl technique. This essentially consists of towing a funnel-shaped net leading into a bag over the sea bottom behind a boat. Otter boards (or doors) are used to keep the trawl nets open horizontally whilst being towed. During fishing the prawns jump up from the soft mud sediment into the net, leaving some prawns behind. A separate large mouthed bag (crab bag) acts to retain blue crabs, while prawns flow to the cod end. The crab bag reduces crab mortality, incidental damage to prawns and allows the crabs to be discarded alive to the sea.
As the prawns are all snap frozen at sea, availability is consistent and year round.
Spencer Gulf King Prawns are packed in the following grades:
- Under 6 pieces per lb (13 per kg)
- Under 8 pieces per lb (18 per kg)
- 10 to 15 pieces per lb (22-33 per kg)
- 15 to 20 pieces per lb (34 –44 per kg)
- 21-30 pieces per lb (45 –66 per kg)
Methods to market
Spencer Gulf King Prawns are sold frozen only packed in 10kg cartons in either cooked or raw (green) forms. Some value added prawn products are available from specialist processors.
Handling and storage
Frozen prawns should be thawed quickly at room temperature by removing from carton and immersing in iced, salty water.
When thawed, prawns should be placed on tray sitting on ice, inside a sealed container. Thawed prawns should be used within 24 hours – green prawns will begin to oxidise and blacken within several hours.
Fresh v frozen
Don’t be afraid to buy frozen prawns. The integrity and quality of prawns processed and packed frozen from live will always be superior to one which has endured days of variable handling in a fresh state.
The raw whole Spencer Gulf King Prawn is light peach in colour with a translucent electric sheen distinctly characteristic blue tail and legs. The raw meat is a light translucent grey/white colour. The cooked meat has a light peach orange skin with a bright, white flesh.
Spencer Gulf King Prawns are characterised by having a deep rich savoury flavour underpinned with a subtle vanilla sweetness and a fresh iodine zing on the finish.
Prawn meat yields 50-55% from gross weight
As a guide to buying prawns, firstly see it has all of its legs, feelers and eyes in tact and that the tail has a firm spring when curled. Smell the prawn – it should have a crisp, clean iodine aroma, with absolutely no signs of ammonia, old fish or brackish water. Peel it and give it a taste – it should be firm in texture and immediately sweet, with long clean finish and no strong aftertaste.
If using a prawn for a hot dish, buy them green and cook them only once. If you are using them for a salad or eat them as they are, buy them pre-cooked. A prawn cooked from live and then refreshed in brine ice will always be firmer, crisper and sweeter than a dead, green prawn put through the same process.
1. Spencer Gulf King Prawns graded from (top) under 6 pieces per lb
2. Defrost prawns by placing prawns in cold salted water, then drain in a raised liner
3. Twist head from tail and draw slowly away from body – pulling the tract from the tail
4. The tract should pull out easily
5. Grip the shell between thumb and forefinger and twist from body meat
6. Prawn meat typically yields 50-55% from gross weight