The yellow, yellow-green or orange stuff in crabs is called the hepatopancreas and though it does not look very appealing, it is edible. It is also referred to as crab fat, crab mustard or tomalley. When eating boiled or steamed crabs, it is considered a delicacy. 

It should be eaten in moderation as it does contain a high level of polychlorinated biphenyls (PCBs).

In large concentrations, it can have some negative health effects. It can also contain toxins associated with paralytic shellfish poisoning.

What is Hepatopancreas (Yellow Stuff in Crabs)?

The yellow stuff found inside crabs is called the crab’s hepatopancreas, often referred to as the “crab butter,” “crab mustard,” or “crab fat.” It is an organ that serves various functions, including digestion and nutrient storage.

It also filters the impurities and contaminants from the crab’s blood and works to produce digestive enzymes. It is similar to our digestive system. Basically, the hepatopancreas is a filter that will catch all the toxins in their body.

This gland will have small branched tubes that are located on both sides of the crab’s mid-gut. It is found directly under their top shell.

Learn more about the crab biology at Chesapeake Quarterly.

Can You Eat the Yellow Stuff in Crabs?

Yes, you can eat it with two exceptions; children under the age of 5 should not eat it. It is also thought that it can increase chances of causing cancer and miscarriage in pregnant women.

It’s recommended that if you eat a lot of crabs, you should not eat the yellow stuff inside from more than six crabs a week.

If you buy crabs, make sure it is from a reputable place and that they fish in clean waters

How To Remove the Yellow Stuff in Crabs?

Turn the crustacean upside down so that the belly side is facing up. Look for a triangular-shaped flap called the “apron” on the underside of the crab. You’ll see it in the center, between the crab’s back legs.

Once you remove the apron, use your fingers to scoop out the contents of the crab’s body cavity. This includes the gills, also known as “dead man’s fingers,” and any other soft tissues or organs, including the yellow substance. Discard these parts.

How to Clean Crabs Before Cooking

Cleaning crabs before cooking involves removing the undesirable parts while preserving the edible meat. Here’s a step-by-step guide on how to clean crabs:

1. Prepare a large pot of boiling water: Fill it with water and bring it to a rolling boil. Make sure the pot is large enough to fit all the crabs in.
2. Remove the crab’s top shell: Hold the crab firmly with one hand and lift the pointed flap or “apron” on the underside of the crab. Pull it upward, away from the body, until it separates and comes off. Discard the top shell.
3. Remove the gills: Lift the sides of the crab’s body to expose the feathery gills on each side. Grasp the gills firmly and pull them away from the body, discarding them. The gills are not edible and should be removed.
4. Rinse the crab: Hold the crab under running water or submerge it in a basin of clean water to rinse off any debris or sand.
5. Break the crab into halves or quarters (optional): You can use a knife or a crab cracker to break the crab into halves or quarters for easier handling and faster cooking. 

Now, the crab is cleaned and ready for cooking. You can proceed with your preferred cooking method, such as steaming, boiling, grilling, or stir-frying. Remember to follow the specific recipe instructions for cooking times and seasoning to enjoy your delicious crab dish.

To Sum Up

The yellow part of the crab is called the hepatopancreas and is part of the crab’s digestive system. It is edible, although some will not eat it because of what it does for the crab while it is alive. It does have a strong taste that may turn some people off from eating crabs.

However, keep in mind that many people enjoy eating this part as it adds flavor to the crab meat. It’s up to you whether you choose to remove it or leave it intact before cooking.