This question has many variables which need to be addressed before we can actually say, how many prawns are in a kilo. The biggest of these questions is, ‘What type of prawn are you talking about?”
You see, prawns vary greatly by species, season and location in which they were caught.
On average, your standard amount of Australian prawns per kilo is, 25 prawns per kilogram, though let me explain the variables.
Prawn species vary greatly in size and within the species, they can also vary in size again, on top of this, farmed prawns versus wild prawns will also vary in size!
Prawn sizing within the industry is officially done with a simple rating system that works in pounds. To convert the pound number to the number of prawns you can more or less double the number without too much error.
PRAWN SIZE RATINGS;
U1 (Giant) – 1 Prawn per kg
U2 (Giant) – 4 Prawns per kg
U3 (Giant) – 6 Prawns per kg
U4 (Giant) – 8 Prawns per kg
U5 (Giant) – 10 Prawns per kg
U6 (Huge) – 12 Prawns per kg
U7 (Huge) – 14 Prawns per kg
U8 (Huge) – 16 Prawns per kg
U9 (Huge) – 18 Prawns per kg
U10 (Huge) – 20 Prawns per kg
U11 (X-Large) – 22 Prawns per kg
U12 (X-Large) – 24 Prawns per kg
U13 (X-Large) – 26 Prawns per kg
U14 (X-Large) – 28 Prawns per kg
U15 (X-Large) – 30 Prawns per kg
U16 (Large) – 32 Prawns per kg
U17 (Large) – 34 Prawns per kg
U18 (Large) – 36 Prawns per kg
U19 (Large) – 38 Prawns per kg
U20 (Large) – 40 Prawns per kg
U21 (Medium) – 42 Prawns per kg
U22 (Medium) – 44 Prawns per kg
U23 (Medium) – 46 Prawns per kg
U24 (Medium) – 48 Prawns per kg
U25 (Medium) – 50 Prawns per kg
U26 (Small) – 52 Prawns per kg
U27 (Small) – 54 Prawns per kg
U28 (Small) – 56 Prawns per kg
U29 (Small) – 58 Prawns per kg
U30 (Small) – 60 Prawns per kg
The largest prawns you will most likely come by are King Prawns. King prawns come in many varieties thought the Eastern King Prawns (Penaeus plebejus) and the Western King Prawns (Melicertus latisulcatus) are the most readily available U6 – U10 rated prawns in Australia. So expect 12-20 prawns per kilo. These are your classic prawn cocktail prawn of choice because they look so impressive!
Moving down to the well known Tiger Prawn and while these can grow to be U8, it’s more common to find them around the U10 – U15 range, meaning 20 – 30 Tiger Prawns per kilo.
Around the same range and stretching further down the size chart is the Banana Prawn that you will most commonly find in the supermarket. These generally range between U12 and U20, meaning 24-40 Banana Prawns per kilo.
In saying this, these species will sometimes be larger or smaller than average and it’s not uncommon to find a huge prawn within your purchased kilo. Likewise, you will normally get some small little runts in your purchase.
FARMED VERSUS WILD PRAWN SIZES
Twenty years ago farmed prawns were substantially smaller than wild-caught prawns though with the modern advancements in fisheries and overfishing the oceans, it is now more common than the farmed prawns are larger than the wild-caught versions of the same species.
Prawn farms like to constantly purchase “Leader Prawns” from trawlers. Leader prawns are monsters that can weigh in at close to 500g each. A breeding pair of Leader prawns can produce up to 1 million babies within a year, though those numbers drastically drop off after the first year, hence why prawn farms like to renew their breeding stock regularly.
LARGEST EVER PRAWN CAUGHT
The biggest prawn ever recorded was a Giant Tiger Prawn that weighed in at nearly 600g, making it a U1 rated prawn. This is not an uncommon occurrence either. Most wild prawns will have a ‘Giant’ variant in their DNA which will allow for growth far bigger than the average of that species.
Giant prawns are frequently caught in the wild though never in prawn farms. When a trawler picks up a couple of Giant Prawns, chances are the boat crew will eat well that night. The reason for this is simply because it is so far outside the ‘normal’ prawn experience we are used to, that there is no real market for them. Imagine trying to peel and eat a prawn that is the size of a puppy…. Yeah, I don’t want to think about that either.
So how many prawns will you get per kilo? The politically correct answer is…..It depends. If you need a certain amount, then order a certain amount, but if you don’t care, then order yourself a kilo, grab a beer and enjoy your afternoon.