Why do blue gray crabs turn orange red when cooked?

Before the crab is cooked, we will clearly find that the crab is blue-gray, but after the crab is cooked, we will find that the crab turns red, and some crabs will turn orange, so why does this phenomenon occur? This is because crabs have astaxanthin on their bodies.

And this astaxanthin turns orange red during the cooking process.

This is because the high temperature destroys the color of astaxanthin, which is why this happens. <>

The body of the crab is shrimp with shrimp and cyanin, which cannot be seen in a low temperature environment, but in a high temperature environment.

Among them, we can see the presence of astaxanthin very carefully, so we will find that at the beginning, the crab is a very normal color, but after cooking, the color of the crab has changed to an unexpected orange-red. The taste of crab is very good, many people like to eat crabs, and here is also a suggestion that if you also like to eat crabs, you should also pay attention to the amount. <>

Although crabs are very tasty, they should not be eaten too much, especially if they are pregnant or have some body chills.

Eating too many crabs can cause very serious damage to your body, and crabs are cold foods. If a pregnant woman eats too many crabs, it is easy to have a miscarriage, so many pregnant women do not dare to touch crabs during pregnancy, even if they are normal people, they cannot eat too many crabs. There are also things like gout.

Patients should also not eat crabs because crabs are high purines.

food. <>

If you like to eat crabs, you can also choose to try it occasionally, but don't eat too much, otherwise it will easily bring some pain to your body. If it's not particularly fresh crab, you can choose to make it into a spicy crab.

If the crab is very fresh, it can be made into steamed crab.

Because there will be some astaxanthin in it, it will turn orange-red after cooking. It may also shrink. And there will also be some carotene in it.

The reason why blue-gray crabs turn orange-red after cooking is because this is a kind of astaxanthin in the crab's body, and this element will produce a certain reaction after cooking, resulting in overall discoloration.

Because crabs have some astaxanthin in them, which changes when heated, they are orange-red when cooked.

Why is crab gray when it is undercooked? Why is it red when cooked?

Isn't it the same with shrimp?

Under normal conditions, the shells of live crabs and shrimp are turquoise. But when the crabs and shrimp are in the pot. Most of the pigments are decomposed when exposed to high temperatures, only astaxanthin is not afraid of heat, and will not decompose when exposed to high temperatures, but will show a bright red color.

So, the boiled crab and shrimp turn red.

It turned out that the shells of shrimp and crabs contained astaxanthin, which is the main pigment component of this type of crustacean, itself red.

Interestingly, although astaxanthin has the word "shrimp" in its name, it does not come from organisms such as shrimp and crabs. Astaxanthin is mainly derived from freshwater algae, bacteria, and phytoplankton, and these algae will produce astaxanthin in the body when the external living environment increases salinity and sunshine hours.

Crustaceans such as shrimp and crabs feed on these astaxanthin-containing algae, bacteria and phytoplankton for a long time, resulting in higher levels of astaxanthin in their bodies and shells.

Escape from protein.

When shrimp and crabs are still alive, astaxanthin and other proteins are combined, making it difficult to show their original bright red color.

However, when heated, the protein in shrimp and crab is denatured and degraded, and the astaxanthin that was originally bound to the protein will "escape" out, and the shell of shrimp and crab will gradually reveal red.

Among them, shrimp and crabs generally have less astaxanthin in their abdomen. Therefore, after heating, the red distribution of the abdomen of shrimp and crab is less.

Why do boiled crabs turn red It turns out that the color of the crab's body surface is mainly determined by the pigment cells in the carapace dermis. When the crab is heated at a high temperature, many of the pigments in it will be destroyed one by one. However, there is a property called astaxanthin in it that is more stable, and it is not easy to be destroyed when it is high temperature, so that astaxanthin can be separated from the protein, thus showing its original red color, and the crab's body will magically turn red.

This is mainly because there is a pigment called astaxanthin in the crab's body, and when the crab is cooked, the astaxanthin will be separated from the protein, and the astaxanthin will show its original color, and the crab will turn red.

The contents of the shell are chemically reacted at high temperatures.

Because when the crab is not cooked, its color is gray, but after cooking, through heating, the color is received, and after the temperature is heated, there will be some oxidative changes to turn red

The dermis under the crab carapace contains four pigment cells: red, yellow, blue and cyan, and when the crab is heated to 100 degrees Celsius, the yellow, blue and cyan pigments will be decomposed and disappear, but the red pigment will not be destroyed, so that the cooked crab will show a bright orange color.

Crabs belong to the class molluscs, decapods, the body is protected by a hard shell, and breathe by gills, in terms of taxonomy, crabs and shrimp, lobsters, and hermit crabs are the same kind of animals.

There are about 4,700 species of crabs in the world, and about 800 species in China, and the main ones eaten are three-wart crabs, far-sea pike crabs, blue crabs and Chinese mitten crabs.

The red pigment contained in the dermis of shrimp is also called astaxanthin, which gathers more in the crab head, chest and feet, and rarely in the abdomen, so the phenomenon of crab cooked belly is usually white.

Because the color on the crab shell comes from a variety of pigments, including shrimp and crab white, the shrimp blue crab white interacts with the red astaxanthin to produce a blue-green color. When the crab is cooked, the white of the shrimp and crab is decomposed, leaving only astaxanthin, so it turns red. <

Because the color on the crab shell comes from a variety of pigments, including shrimp and crab white, the shrimp blue crab white interacts with the red astaxanthin to produce a blue-green color. When the crab is cooked, the white of the shrimp and crab is decomposed, leaving only astaxanthin, so it turns red.

<>1. The red color of the crab shell is not necessarily ripe, it may be the color of the raw crab itself, although the astaxopene in the crab shell will form other colors after combining with protein, but it is also possible to want to eat orange and red, so the naked eye sees that the orange red crab is not cooked, but alive.

2. It is also possible that the crab is cooked at high heat, but the cover is not ripe, because the crab shell is on the outside, so cooking will be the first to contact the heat, so it will soon turn red, but at this time, the flesh inside may not be ripe, so the crab shell turning red cannot be used as a criterion for judging that the crab is cooked.

3. Crab boiling time: boil crab for 15-20 minutes, but due to different types of crabs, the amount and volume will be different. Generally speaking, crabs with 3-4 taels should be boiled for about 15 minutes, and crabs with more than 4 taels should be boiled for more than 20 minutes to cook

The boiling time of crab should not be less than 15 minutes, otherwise it is difficult to achieve the effect of sterilization. When you open the crab lid and see that the meat on the crab lid has solidified, it means that the crab cover is completely ready.