Should you Purge Crawfish? (To Do or Not To Do)

One of those Southern American dishes that are hard to understand without experiencing it yourself is the backyard crawfish boil.

Able to be made in almost every kind of dish you can think of these little water creatures are often enjoyed when made in the simplest of ways.

However, there are a few things that you may be wondering about before you start cooking these southern delicacies, like how do you thoroughly clean them.

You do need to purge crawfish before cooking them, this will clear out any dirt and grass that will be stuck in their intestinal tracts. The process of purging your crawfish involves a lot of water and constantly checking to see if any have died, however, doing this will ensure that your crawfish taste a lot better.

There are several myths and techniques regarding the best way to clean and purge a crawfish.

With every big cook believing their way to be the next best thing, making it harder and harder for you to start making crawfish when you are still learning.

Some of the best techniques cannot simply be found online and knowing what works the best is a hit or miss.

You can learn how to purge crawfish and boil some great crawfish with our complete guide here!

Why should you purge crawfish?

Crawfish are not like shrimp or lobsters that live in oceans and get to live in relatively clean waters.

While you need to clean the larger brothers of crawfish, they do not need to be purged, this is because the water that many crawfish live in will be very muddy.

Usually farmed in freshwater ponds, crawfish live in mud and eat almost anything they can.

This makes them perfect little cleaners in your fish tank, but when you want to eat them this means you will need to watch the mud off them.

You have to purge a crawfish to get rid of the last things it ate, usually grass and mud. These things may not be harmful once cooked thoroughly; they will still greatly affect the taste of the crawfish. Usually making them quite tart and unpleasant to the pallet when eaten, even when you cover them in a giant dollop of sauce.

How to purge crawfish?

Crawfish are commonly referred to as mudbugs because they are harvested out of muddy freshwater ponds. Because of this you will need to give them delicious mudbugs a bath to remove the musty or earthy flavor associated with crawfish.

Everyone one in the crawfish community has a different purging method. Some people will add salt to the purging process while others don’t even bother. They just dump them in the boiling water.

I just use water and keep washing them until the water is clear. This is by far one the most labor-intensive process of boiling crawfish.

But it is also the most important step to boiling crawfish. If you do not purge and pick out the dead craw fish you will end up with some of the nastiest tasting crawfish.

You will need an ice chest or wash tub, paddle and a water hose. You will dump the crawfish into the container and fill with water.

When the container is filling with water you will be able to see the water turning dark from the mud washing off the crawfish.

With a paddle, spin the crawfish around and be sure to pick out any dead crawfish. They will typically float to the top of the container during the purging process. Then dump out the water.

Repeat the process till the water in the container turns clear.

How long should you purge crawfish?

Once you have your crawfish and you have your buckets and tools ready you may be wondering just how long you should be washing them.

A confusing question to only be asking when you already have sack of crawfish in one hand and a hose in the other.

The simple indicator will be that the water you are purging the crawfish in will start to go clear.

If you are using an advanced tool the water that exists will be clear while in a simple bucket the crawfish will be purged once you add water and after a few minutes there is no discoloration.

One thing to remember about crawfish is that they are not boiled already dead, and while purging it is vital that the crawfish still be alive.

It is recommended that you remove any dead crawfish during this period, they will usually float to the top, as you should not eat any dead crawfish.

What do you use to purge a crawfish?

There are many questions that you will be asking yourself while getting ready to purge your crawfish, one of the first ones you should be asking is what are you going to put the crawfish in while doing this task.

Whatever you use will have to be large enough to hold all the crawfish, provide enough water for them to purge themselves, and light enough for you to pick up to be able to dumb them into a pot of boiling water.

The most often used tool in the middle of nowhere will be a plain bucket, simple and easy, however, there are more sophisticated tools out there.

Cowboy’s Crawfish Washer

The Cowboy’s Crawfish Washer is a simple tool that has made the job of purging crawfish a tedious intense battle against you and crawfish water into one of ease.

This specialized bucket has an inlet and outlet for the water to go into the bucket. Building a system that constantly lets in clean water, while draining the dirty water.

This simple washer system saves a lot of time and water by allowing you to easily drain the water out and not have to deal with catching the crawfish as you tip the bucket.

Can you purge crawfish overnight?

Once you have done one purging process for crawfish it may be tempting to find a less involved process where you can easily purge them.

Something that many firsttime crawfish makers are tempted to do is to leave the crawfish in a clean tub filled with water overnight, which makes some sense.

You cannot purge crawfish overnight; crawfish need some access to fresh air to breathe and leaving the crawfish in a bucket of water will kill them. Many first-time crawfish makers forget that you need to prepare and boil crawfish while they are still alive.

While leaving them overnight in a bucket of water will certainly purge the crawfish it will also kill most if not all of them.

This will cause them to immediately start rotting and the only smell and taste you will get from these crawfish will be a strong one of ammonia.

Rather work a bit harder to enjoy the food you are about to make than attempt a shortcut that will ruin the food for everyone.

Do you use salt to purge crawfish?

One of the things that have become myths in the world of crawfish, strongly associated with extremely false old wives tales, is the use of salt when purging.

Many times, you will see people suggest using salt to fully purge the crawfish, claiming that this will induce vomiting and other openings of intestines within the creatures.

This is not true; salting does not work to purge crawfish any better than normal freshwater would help. The only proven effect salt has on crawfish is inducing pain, which does cause them to squirm around a lot until fresh water is poured over them. If you watch the process you will be able to see that the crawfish only start vomiting once freshwater has been added.

However, the effect of causing pain is not the only reason you should not salt crawfish before boiling them. The bigger danger of salting crawfish is that you will kill a significant amount of them when doing so.

Causing you to lose a lot of the crawfish you either bought or went out of your way to catch.

How do you store crawfish?

If you are not going to be eating the crawfish immediately you will need to find a way to store them, and this can be an adventure in itself.

Many people will make the mistake of placing the crawfish in a big tub of water, assuming this is what they will want. However, as discussed before, this will kill the crawfish.

To store crawfish for an hour or two until ready to cook simply keep them in the sack they came in and wash it off briefly with a hose, placing it in a shaded area.

Storing crawfish for a longer time you need an ice chest large enough to place the sack of crawfish in and some ice.  Make sure to have the drain plug on the ice chest unplugged .This technique should help them last one or two days.

Crawfish will die if not fed properly and kept in a full tank, which is why people usually eat them as soon as they catch or harvest them.


Purging your crawfish is a simple process of providing them with clean water until they have purged all of their internal gunk.

When you do this it will also clean off all the outside dirt and filth that are on the crawfish shells. The process is simple and easy to do, especially if you have the right tools.

Just be sure you don’t get any crawfish that make an escape attempt, these little mudbugs can be surprisingly quick if need be!




Jacob James

Jacob James and his family have been involved in the seafood industry for over 100 years on The Alabama Gulf Coast. He grew up on His grandfather's shrimp dock in Bayou La Batre, Al. He has great respect for the commercial fishing industry and understands the hardships that this industry faces. His focus is to bring awareness of the lost traditions and customs of the Gulf Coast by writing about the ways of keeping tradition.

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