Do Blue Crabs Need To Be Purged?

Callinectes Sapidus is the technical name for blue crabs, translated from Latin, means ” beautiful savory swimmer.” They are found alongside the coast of the Atlantic ocean and in the Gulf of Mexico, and crabbers everywhere have very decided and dogmatic views on which is the best way to prepare them.

Some say that blue crabs need to be purged, which helps remove harmful toxins and bacteria while making them sweeter. An equally large group of people insist that purging is unnecessary and that boiling or steaming will remove harmful substances.

If you have heard both sides of the story and are still unsure, this article sets out why you should purge and the opposing perspective. Whatever you do decide, the choice is yours.

Should You Purge Blue Crabs Before Preparing Them?

Whether to purge crabs or not is an often hotly debated topic, where many say that eating crabs straight off the reef and washing off any grit has done them no harm.

Do they claim that if the sea or river creek mud outside the shell flavors the meat, why try diluting or removing it?

The other point of view is that not purging the blue crabs opens the potential for food poisoning or worse, and rather take all of the safety precautions possible. Placing the crabs in a freshwater tub will cleanse them of toxins and enhance their taste.

However tasty the meat, it can’t be denied that crabs are nasty bottom feeders and scavengers. As such, they have consumed any gunk which has come across their path.

Whether you should purge blue crabs before cooking them depends largely on where you caught them and your attitude to risk. Purging the blue crabs caught in a muddy river will go a long way to removing the taste of the mud.

There have been blue crab caches in several rivers, so cleaning out any river debris and impurities that may have been ingested is important.

If the crabs have come from the beach (a very sandy area), purge them to remove any impurities brought in with them.

The whole point of purging and cleaning blue crabs is to ensure that the final offering on the customer’s (or your) plate must be as clean, intact, and as healthy as possible.

When you purge the crabs, you can generally watch them purge out all the gunk in them. That said, cooking a crab in boiling water or steam will almost guarantee killing bacteria or other microbial impurities.

Initial Cleaning And Purging

To prepare and purge the crab, follow the process listed below.

  • Tie the crab claws together with claw bands as this will help keep them intact and stop other crabs in the bucket from ripping off other crabs’ claws. Check it out on Amazon below.

  • Use a semi-stiff brush, and while holding the crab under a  tap of running water, brush the top shell and underbody by removing sand, dirt, algae, and other debris attached to the surfaces.
  • Let them purge out the funky river water for up to sixty minutes. When filling the bucket with water, use the sprayer and hose off any muck left after brushing them.
  • Drain the dirty water, then replace it with fresh. Substituting fresh water for salt doesn’t change the flavor since you are only cleaning out the gills (I would never do this with my seaside oysters!), and it is only for a short period of time.
  • Place the cleaned and banded crabs into the freshly filled bucket (salt or freshwater is fine), but only give them enough fresh water up to the eyeballs.
  • If it is too full, the crabs will use all the oxygen and drown, so it is important to leave enough breathing room on the surface.
  • Install an old aquarium powerhead which will introduce a current, and the filter head part will introduce oxygen into the water. Check it out on Amazon below.

  • While the crabs only need to purge for up to an hour, this method can keep the crabs alive for up to five days.

Safety Note with catching, cleaning, purging, and Cooking Blue Crabs,  if a crab dies before you get to cleaning or cooking it, the safest thing to do is to throw it out to avoid getting food poisoning.

Kill And Prepare The Crab.

The best, most humane way of killing crabs is as follows.

  • Pour salt water into a cooler box with a large quantity of ice in it.
  • Place the crabs into the saltwater and ice slurry.
  • It will slow them down and take any fight out of them.

Prepare The Crab

  • After a few minutes, take the top shell of the top shell off
  • Pull the mandible (face) off (The Mandible consists of a pair of mouthparts used for either biting, cutting, and holding food,  both eye orbits, eye stalks, two antennas, mouth, Cephalic (Head), Rostrum (Beak or nose)).
  • Crab gill is not edible, so discard them by pulling them off.
  • Then pull the pin, which involves removing the “apron,” which is a triangle-shaped shell on the bottom of the crab (on males, it is smaller and narrower, while on female crabs, it is bigger, wider, and more rounded).
  • Grab the point towards the front of the crab and pull it off.
  • Pull the lungs off.
  • The yellow “mustard” is called the hepatopancreas, one of the main parts of the blue crab’s digestive system. This substance is edible and is considered a delicacy to some, while others throw it away.
  • Rinse the rest under a tap

Prepare them by boiling or steaming them in whichever way works best for you.

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In the final instance, whether you purge or don’t purge the blue crabs you brought home is entirely up to you and the traditions you are most comfortable with. Some say that it is a waste of time and that throwing the crabs straight into a pot is sufficient, while others say that it removes impurities and makes the crabs taste sweeter.

Whatever you do, crabs taste great and are a sustainable food source for areas where they populate.