Updated: Jul 18, 2022
Often, the terms "prawns" and "shrimps" are used interchangeably. Both are caught, farmed, sold and served all the world over. However, are they actually the same? Did you buy some prawns or shrimps; how are they different; do they taste the same? These are some of the questions that I will try to cover here.
Whether one calls a prawn a "prawn" or "shrimp" may be determined by where you live. In the UK, Ireland, Australia and New Zealand, "prawn" is generally used to describe both true prawns and shrimps. In North America, the term "shrimp" is used much more frequently, while the word "prawn" usually refers to larger species or those fished from fresh water. In Singapore, we generally call our crustacean "prawns", their smaller counterparts "shrimps", as is the case with dried shrimps (虾米).
What a large prawn I see?
If so, it is difficult to know exactly what you have purchased since the terms are not consistently used. One thing for sure: both prawns and shrimps are from the crustacean family and are members of the decapod order, i.e. they are 10 footed. Shrimps belong to the pleocyemata suborder which includes crayfish, lobsters and crabs. Prawns, on the other hand, belong to the dendrobranchiata suborder.
Prawns and shrimps have a thin exoskeleton and their bodies are divided into three main segments: head, thorax and abdomen. Typically, prawns are larger than shrimps. To know if you bought prawns or shrimps, look at the shell. Prawns have the segments overlap down the abdomen. Shrimps have their second segment overlap the first and third segments. This means that a shrimp have more of a bend or curve to their bodies than prawns do.
Can you tell the crustaceans apart?
If you examined them closely, prawns have claws on three of their legs, with the second pair being the largest. Shrimps have claws on two pairs of their legs, with the top being the biggest. Prawns have branching gills while shrimps have plate-like (or lamellar) gills. Prawns release their eggs into the water for hatching while shrimps carry their eggs on their bodies until they hatch. Both prawns and shrimps can be brownish, bluish, pinkish or gray but take on an orange hue when cooked.
Interestingly though, there is no standard size that sets a prawn or shrimp apart. Each kind comes in a variety of sizes, depending on the species. The crustaceans are classified by count per pound. Generally speaking, "large" usually means you will get 40 or fewer prawns or shrimps per pound. "Medium" refers to about 50 per pound, and "small" means about 60 or more per pound. (Note: 1 pound = 0.453592kg) Besides these, some are labelled extra large, jumbo or even colossal.
Choosing the right sized prawns or shrimps is not too complicated, actually. If you check the label on a prawn packaging, and it says "16/20", this simply means every pound contains between 16 and 20 prawns. The per pound counts above refers to the peeled and deveined shrimps or prawns, which means any heads, shell and tails have been removed. Therefore, the smaller the count, the larger the individual prawns. After defrosting fully, prawns can lose between 10 to 20% of their weight. When you go shopping, calculate how many prawns you will need to serve per person.
I guess you may have more questions about prawns and shrimps now, such as their nutritional value, cholesterol content and which type of prawns are recommended for cooking specific dishes, etc. I will cover these in the next part.
Till then, enjoy your prawns, or shrimps.