The End User
Spencer Gulf King Prawns are snap frozen on board the vessels at minus 35 – 40 degrees celsius and stored at that temperature on the vessels which maintains the integrity and quality of the prawns. When the vessels unload, the product is then taken to a commercial freezer which is required to store the prawns at a minimum temperature of minus 18 degrees celsius but most are somewhere between minus 20 and minus 24 degrees celsius. Contrary to opinion that frozen product is not as nice as fresh, frozen prawns will always be superior to prawns that have endured days of variable handling in a fresh state.
Spencer Gulf King Prawns are sold frozen in 10kg cartons either cooked or in their green form. Some value added products are available from specialist processors.
If you are buying prawns there are several considerations. Firstly, see that they have all of their legs, feelers and eyes in tact and that the tail has a firm spring when curled. They should have a clean, crisp iodine aroma with no signs of ammonia, old fish or brakish water. It should feel firm in texture and when you taste the meat it should be immediately sweet, with a long clean finish, no strong after taste.
Frozen prawns should be thawed quickly at room temperature by removing from the carton and immersing in iced, salty water. When thawed they should be placed on a tray sitting on ice, inside a sealed container. Frozen prawns should be used within 24 hours after being thawed. Do not freeze prawns that have been thawed as you will greatly reduce their quality. Ensure you use green prawns as soon as you can after defrosting as they will begin to oxidise and blacken within several hours.
If you are using the prawn for a hot dish, buy them green and cook them only once. If you are using them for a salad or for eating 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 green prawn that has gone through the same process.
The Seafood of the Eyre Peninsula Guide http://www.seafoodfrontier.com.au/brand_media_full_story.cfm?SectionPageID=42&NewsID=200007