Snow crabs are widely distributed on the east coast of Korea, and in the case of Japan, they are often caught in the southwest sea of Sea of Japan. It is also distributed in the Okhotsk Sea, Kamchatka, Bering Sea, Alaska Sea and Greenland. However, the East Sea of Korea and the Japanese Islands are mainly distributed at a depth of 200-400m on the west coast.

The habitat of snow crabs is sandy or mud with a depth of 200-400m. Water temperatures are resistant even at water temperatures higher than 0-13°C, but resistance to high temperatures is very weak, so they mainly live at cold temperatures below 3°C

Snow crabs are relatively omnivorous, such as crustaceans (crabs, shrimp, etc.), small fish, cephalopods (squid, octopus, etc.), and polymorphs (dog worms, etc.).

The appearance of red crabs (red crabs) is similar to Yeongdeok snow crabs. If you look closely, the body of the red snow crab is crimson, and both the back and belly are red, but in the case of Yeongdeok snow crab, the back is close to orange and the belly is slightly yellow, but it is close to white. In terms of morphological characteristics, the two rows of granular protrusions on the side behind the shell are combined into one row in the case of red snow crabs, but the snow crabs lead to two rows to the front edge. Another distinction is that in red snow crabs, there is one small thorn each on the left and right sides near the maximum width, but in the case of snow crabs, there is no such small thorn.

Recently, a considerable amount of so-called Neoggae crab, which is thought to be a variant of Yeongdeok snow crab, has been captured in coastal waters. Neodo snow crab is presumed to be a natural hybrid of Yeongdeok snow crab and red snow crab (red snow crab), but it also has morphologically intermediate characteristics, and the depth of distribution that inhabits is also intermediate between Yeongdeok snow crab and red snow crab. In Yeongdeok, it was also called Cheongge before it was announced as Neogae by the National Institute of Science. Red snow crab and Yeongdeok snow crab have a significant difference in taste and value. In particular, with the reduction of the fishing grounds due to the Korea-Japan fisheries agreement, the quality is somewhat lower than that of Yeongdeok snow crabs, but the discovery of the resources of Neogae crabs, which are much more commercially available than red snow crabs, is significant. The current law does not separately classify Neogaege, which is believed to be a variant of snow crab, but it is processed in accordance with Yeongdeok snow crab.

Chitin is a substance that is widely distributed in the shells of crustaceans and insects, fungi and mushrooms, and is mainly obtained from the shells of crustaceans, and is the only animal dietary fiber on Earth with a structure very similar to cellulose. Therefore, it has the characteristics of this dietary fiber and the unique characteristics of adsorbing fat and heavy metals, so its use value and applicability are highly expected.

Chitosan is a natural polymer material obtained by deacetylating (D/A) chitin under high temperature and strong alkali conditions and combined with 5,000 or more glucosamine. The most ideal chitosan is chitosan containing 100% glucosamine residues. In other words, it refers to 100% D.A. treatment of chitin (refined system 100%), which is generally called chitosan if it is more than 60%, and the domestic standard is 70% and 80% in Japan.

Chitosan oligosaccharides are obtained by hydrolysis of polymer chitosan. In other words, it is easy to absorb chitosan, a polymer substance of more than 5,000, as a key to the quality of chitosan oligosaccharides, and more than 5,6,7 sugars are attracting attention as they are known to have excellent medical effects and are also being developed as a cancer treatment.