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Why Do Crabs Have To Be Cooked Alive?

By: Author Robert Greene

Posted on Last updated:

Why Do Crabs Have To Be Cooked Alive?

Crabs, along with lobsters, crayfish, and muscles, are among the edible crustaceans that are enjoyed by millions of people throughout the world each year.

They serve as an important source of protein and are standard fare in some of the finest restaurants & grocery store brands.  The standard method of cooking live crab, however, is a controversial issue that some feel is cruel and contrary to animal welfare. So…why are crabs cooked alive?

Well, if you are going to eat crab….the alternative of cooking already-dead crustaceans can be dangerous to one’s health, due to the bacteria that lurks beneath their shells.

Do crabs and other crustaceans hold a health risk to humans?

The Journal of Food Protection published a study conducted by the National Research Institute of Fisheries Science that supports the theory that crustaceans, such as crabs, do indeed present a health risk to humans that increases when they are not handled properly during processing.

Those who choose to cook crabs after they are deceased, rather than cooking them alive, take potentially fatal health risks.

How does boiling crabs alive affect the presence of dangerous bacterium?

According to an article in Science Focus (online), when crustaceans die, the dangerous, harmful bacteria found in and on their bodies and shells can multiply quickly, releasing toxins from crab meat that may not be destroyed simply by cooking. This is used as the rationale behind cooking them alive.

Vibrio parahaemolyticus bacterium

Among a variety of other pathogens, researchers studying crabs and other crustaceans have discovered a particularly dangerous marine bacterium, Vibrio parahaemolyticus bacterium, that can cause food-borne diseases.

Researchers looked at both salt water and fresh water crabs and discovered that this dangerous bacterium appeared in the bodies, shells, and feces of a number of crab species. The study focused on crabs in Chinese markets where live animals and produce are sold for human consumption.

The bacterium can spread through the animals’ bodies almost immediately after death and has the potential to spread to other crustaceans.

The Journal of Food Protection also advises throwing away any dead shellfish and other crustaceans if they die prior to being cooked. The journal also advises against eating shellfish, including crab, that is raw.

What types of illnesses can be caused by eating crabs containing Vibrio parahaemolyticus?

According to the Journal of Infectious Diseases (2000), Vibrio parahaemolyticus bacterium found in crustaceans like crabs frequently occurs in marine animals’ natural environments in both shallow and deep water.

This bacterium is known to cause at least three diseases, including gastroenteritis, which is the most common of the three. Other possibilities include advanced infections to wounds, and septicemia, a blood infection that is potentially fatal.  

Does boiling crabs alive cause the animals to experience pain?

The jury is still out with regard to whether crustaceans experience pain when they are boiled alive, and there is more than one perspective on this issue.

The aforementioned article in Science Focus notes that some people argue that crustaceans do not possess true brains, and therefore, cannot feel pain as sentient beings.

This conclusion was reached after observing that some crustaceans will contort their bodies and make violent attempts to extricate themselves from the boiling water.

he article concludes that these animals do not possess the same type of self-awareness as humans, but that they do exhibit both hormonal and physical responses to tissue damage.

The study went on to say that crustaceans produce cortisol just as humans do when pain is experienced, leading researchers to conclude that shelled marine animals do experience pain. It simply is not clear to what degree they experience it, or if it is pain identical to that experienced by humans.

What are some humane ways to kill crabs and other crustaceans?

In a study written for the Journal of Shellfish Research by Chapman (1992) and Cook, (1996) in 1997, researchers noted that efforts to kill crustaceans like crabs humanely developed the goal of inflicting as little pain as possible during their slaughter.

However, the researchers also took into account the fact that the measurement of pain is a very difficult, if not impossible, thing to measure accurately where animals are concerned, because they do not possess languages that are understandable by humans.

Therefore, attempts at measuring the animals’ levels of pain are usually estimated by changes in their behaviors that appear to indicate that they are in distress.

For instance, a lobster’s tail will twitch for approximately two minutes after the animal is plunged into boiling water, indicating that the animal might be experiencing pain. The authors of the study also noted that changes in the animals’ behavior that make their distress undetectable can be affected by inducing paralysis.

Since the animals are intended for human consumption, different chemicals are used for those particular crabs, as opposed to the ones that are used for research.

Adding to the controversy is the fact that paralyzing crustaceans, however, does not necessarily mean that they will not feel pain when scalded.

It simply means that indications of their pain will not be noticeable to those who cook them, making the practice of boiling the marine animals alive possibly more comfortable for the cooks, but not for the animals who may or may not still experience the associated pain.

Conversely, the view that boiling crabs and other crustaceans alive is cruel has been taken to new heights in the United Kingdom and in a number of other countries.

According to an article in The Guardian, Dr. Stephanie Yu, Ph.D. Noted in her report prepared for the U.S. Humane Society that, “There exists robust scientific evidence in support of crustaceans being sentient animals with the capacity to suffer.”

As a response, a bill has been presented to the House of Lords in England that calls for changes to laws governing the treatment of animals and asks that it include crab, squid, and other sentient invertebrates.

The bill specifies that those who plan to cook, or otherwise kill any of these animals will need to stun them before they are boiled. One method of doing this is by chilling them.

According to Science Magazine, scalding crustaceans to death so that they may be eaten is unnecessary torture that the animals should not have to endure. The author notes that these marine animals can be painlessly killed by placing them in cold, fresh water and raising its temperature to approximately 40°C or replacing their protein with a seafood alternative from a company like BlueNalu.

Alternatively Ray, Fleckenstein, Medley , et al (2018), conducted a study that involved stunning crabs with an electrical shock prior to boiling them, resulting in fewer incidences that indicated the animals were in pain.

More FAQs about Cooking Crab

Do crabs have to be cooked alive?

Crabs must be cooked alive because as soon as they die, they begin to rot and become toxic. It is crucial to note that you cannot cook crabs that are dead. Cooking fresh crabs that are alive is essential, as it makes it easier to clean them after cooking when the meat has loosened from the shell.

Is fresh crab already cooked?

Fresh crab is typically sold pre-cooked in most grocery stores, either frozen or thawed from frozen. The cooking process for crabs is quite simple since they are usually already cooked. All you need to do is heat them up sufficiently while preserving their juiciness and natural flavor.

Can you grill live crabs?

It is necessary to clean your Dungeness crab before grilling. If you are using live crabs, you should steam or boil them for approximately 7-8 minutes per pound and then rinse them thoroughly in cold water. In the case of frozen crab, you can simply let it thaw overnight in the refrigerator.

Why aren’t lobsters killed before cooking?

Lobsters are not killed before cooking because harmful bacteria naturally exist in their flesh, which can rapidly multiply and release toxins after the lobster is dead. These toxins may not be destroyed by cooking, thus posing a risk of food poisoning. Therefore, cooking the lobster alive helps minimize the chance of food poisoning.

How long does a crab live in boiling water?

Crabs and lobsters can survive for approximately four to five minutes and three minutes, respectively, when boiled alive. The audible sounds emitted by lobsters in boiling water are subject to different interpretations – some argue it indicates pain, while others attribute it to the release of gases within the shell.

Why do crabs turn red when cooked?

Crabs turn red when cooked because the heat breaks down the crustacyanin protein, causing the release of astaxanthin, which gives the shell of the crustaceans a vibrant red color. The intensity of the color change indicates whether the seafood has been cooked thoroughly.

Do you clean crab before or after cooking?

The crab is typically cleaned before cooking to minimize mess at the table and allow the flavors to penetrate the body meat during the cooking process. While crabs are usually left whole for crab boils, for other dishes, cleaning them beforehand is quick and easy.

How long do you boil live blue crabs?

The live blue crabs should be boiled for approximately 20 minutes until all of the shells turn red and the meat is no longer translucent. To do this, fill a pot 3/4 full with water and bring it to a rolling boil over an intense flame. Then, add the blue crabs to the pot, cover it, and stir occasionally to ensure even cooking.

What happens if you boil a crab alive?

Boiling a crab alive is often done to minimize the risk of food poisoning because crustaceans, like crabs, naturally have a harmful bacteria called vibrio in their flesh. This bacteria can rapidly multiply in the decaying crab once it’s dead, and cooking cannot eliminate it. Therefore, cooking crustaceans alive helps reduce the chances of food poisoning.

Why can’t you cook dead crabs?

You cannot cook dead crabs because the meat becomes mushy and loses its delicate flavor that is present in fresh crabs. It is recommended to cook crabs within 10 or 15 minutes of their death to preserve the meat’s quality for as long as possible. Although crabs can still be cooked 24-48 hours after death if kept cool, the flavor and texture will be compromised.

Do crabs feel pain?

Crabs do meet the criteria established by scientists to demonstrate their ability to experience pain.

Can you eat live crabs?

You cannot eat live crabs. To ensure a more humane and safer preparation process, it is recommended to place live crabs in the freezer for approximately 15 minutes. This helps numb them, making it easier to remove the rubber bands from their claws before boiling them.

Why are lobsters cooked alive?

Lobsters are cooked alive because it helps minimize the chances of food poisoning caused by bacteria that reside in their flesh and rapidly multiply on their bodies, as stated by Science Focus. Additionally, cooking lobsters in this manner is believed to enhance their taste and presentation when served on a plate.

How long can you wait to cook live crabs?

You can wait to cook live crabs for a good 6 hours or so, as long as you keep them cool. However, it is generally not recommended to wait until the next day to cook a live crab. Additionally, it is important to note that keeping your crab in water is not advisable.

How many minutes should we cook crabs alive?

We should cook crabs alive for approximately 10 to 15 minutes. To do this, start by bringing water to a boil and adding salt and any desired seasoning. Quickly add the crab to the boiling water, ensuring that it returns to a boil. Cook the crab until it floats, which usually takes about 10 to 15 minutes. Once cooked, remove the crab from the water and allow it to cool before serving.

Can shellfish feel pain?

Shellfish can indeed feel pain. Extensive scientific research has unequivocally demonstrated that fish, lobsters, crabs, and various other marine creatures possess the ability to experience pain. The presence of chemoreceptors all over the bodies of lobsters makes them highly sensitive to their surroundings. Consequently, subjecting lobsters to the cruel practice of boiling them alive is particularly inhumane.

How do you put live crabs in boiling water?

To put live crabs in boiling water, you should start by lowering each crab into the boiling water with its legs facing downwards. As the crabs cook, you can simultaneously prepare an ice bath by filling a large bowl with cold water and ice. It is recommended to allow each crab to cook for around 15 minutes. Once they start floating to the top, give them an additional 2-3 minutes.

Can you steam crab alive?

You can steam crabs alive. It is important to ensure that they are alive and active when you purchase them from the market or dock, especially if you plan to steam them at home. The fresher the crabs, the more delicious they will be. Before steaming, be sure to remove any crabs that have died from the batch.

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