Dr. Ding Xin's talk on sea cucumber

At present, China's sea cucumber consumption is very strong, showing that the public health effects of sea cucumber are increasingly important, but the prevalence of misunderstanding of the sea cucumber also exists. Therefore, we had the privilege of visiting Dr. Ding Xin of Northwestern University, who had just returned from the United States for a short period of time. Dr. Ding has been engaged in sea cucumber research for many years, after going to the United States, he and his supervisor separated anti-cancer components from sea cucumbers. Having talents with both the West and East knowledge, he is one of the famous authorities on the research of active substances in sea cucumber.

The first question: Recently sea cucumbers are very popular. Can it cure diseases?

Dr. Ding: Sea cucumber has both nutritional value and medicinal value. Sea cucumbers' protein content is high and the amino acid composition is balanced, which is easy to be absorbed by the body. But people eat sea cucumber apparently not only because of the food value of sea cucumber, but in that protein content of a lot of food protein is also high and amino acid is balanced. People value sea cucumber because it has a high nutritional value and high medicinal value. Its medical value lies in lots of acid mucopolysaccharides, sea cucumber saponins, lipids, and vitamins. So it plays a role in therapeutic function to eat sea cucumbers for a long time. More material above means higher therapeutic value. Different kinds of sea cucumbers have different content of protein and acidic mucopolysaccharide, sea cucumber saponins, lipids, vitamins and so on. Generally speaking, sea cucumbers with high content of protein are of higher value but lower therapeutic value, such as black milk ginseng, eggplant ginseng and so on. Ginseng is not drug but food, so people cannot use it to cure diseases. Treatment depends on formal treatment and drugs.

The second question: Why are some sea cucumbers so expensive, some very cheap? Which sea cucumber is good?

Dr. Ding: the superficial reason of the high price is the market demands, but the root cause is people’s limited knowledge of sea cucumbers. Although the scale of China's sea cucumber aquaculture industry is unique in the world, domestic research and popularization on sea cucumber pharmacy and nutriology lag behind. There are some misunderstandings in books, causing some fundamental knowledge is mis-spread. Although people know that eating sea cucumber benefits their health, but they lack its related knowledge of the therapeutic effect. Ordinary people eat cucumber on the one hand out of superstition, on the other hand based on experience. Japanese sea cucumber price per 500 grams ranging from 2000-4000 Yuan, while the eggplant ginseng only 25-30 Yuan per 500 grams. In essence, the nutritional value of the two kinds of sea cucumbers is not so different. But people have been mistaken for the best Japanese sea cucumber, and they are willing to buy it at high prices. Even some people think that mandragore is not sea cucumber. It is reported that “unscrupulous traders sell sea eggplant as sea cucumber”, which indicates that media don’t know sea eggplant is a kind of sea cucumber. There is no doubt that common people don’t know the point. Some sea cucumber contains high content of mucopolysaccharide, which is good for cardiovascular and cerebrovascular; some with high content of sea cucumber saponins, beneficial to cancer. Like ginseng, if the high content of saponins in sea cucumber, the medicinal value is high, but it may taste bad, not for the dishes; Some sea cucumber contains high content of protein, such as eggplant ginseng and sea cucumber, so it can be used in a large number of hotels and family tables.

The third question: how to distinct the quality? Which one is better, big or small?

Dr. Ding: with different kinds and ways of process, its standards of distinction are also different. According to edible value, sea cucumbers with thick flesh, low content of saponin and small spur are tastier, such as stichopus, mandragore, and white teat fish. According to medical value, sea cucumbers with high content of mucopolysaccharide and saponin are of high medical value, such as square sea cucumber, arctic sea cucumber and plum ginseng. Though the content of saponin in stichopus is not so high, but its content of mucopolysaccharide is high. So stichopus has better medical value. Therefore, as dishes, stichopus, mandragore and white teat fish are good; but for medical function, different patients are suitable for eating different sea cucumbers.

The processing method will also affect the quality of sea cucumber. Imported Japanese stichopus is best, but the quality of the traditional domestic salt ginseng is also very different. As the quality standards of dry sea cucumber in our country are according to salt gray parameters(less than 40% is 1st level sea cucumber; less than 60% is 2nd or 3rd level), it is not surprising that sea cucumbers with 80%salt appear in market. Through boiling of many times, more than 80% of the active substance in salt-ash ginseng is lost. So it is almost no medical value. Plant ash may be good, but coal cash has carcinogenic effects. Shandong has a certain scale of the cultivation of sea cucumber, but there is no standard dry sea in Shandong to participate in the factory. Shandong market sales of dry sea cucumber are mainly produced in Japan. Part of salt-ash ginseng is produced by Japanese sea cucumbers’ boiling of many times in saturated brine, adding magnesium chloride and alum. Large sea cucumbers accumulate high nutritional value, small sea cucumber is poor; but in market, big sea cucumbers are cheaper, small ones mainly in hotels. So it is better for common people to eat large ones in terms of the medical value.

The fourth question: is stichopus the best? What is the difference between Kansas, Ginseng and Korean?

Dr. Ding: Stichopus, whose scientific name is stichopus japonicus, is mainly distributed in Japan, Russia, Korea and China, among which the output in Japan is highest. Different producing areas cause different meat quality. Stichopus is the most widely used sea cucumber, mainly because the sea cucumber body wall saponin content is low and there is no smell. In contrast, the other sea cucumbers, because of the high content of saponin, there is smell but with high medical value, such as square sea cucumber, arctic sea cucumber and topaz.

The fifth question: There are many sea cucumbers on the market. Which is imported, which is domestic?

Dr. Ding: Currently there are more than 100 commercial sea cucumbers in China. They are sold in Yide Road and Dianbai market of Guangdong. On China's market, more than 95% of dried sea cucumbers are imported. Although some large supermarkets marked "Long Island Sea Cucumber", "Bohai Sea Cucumber", in fact, they are produced in Japan or Russia. Even isostichopusbadionotus from South America is labeled as "Long Island Sea Cucumber" by some supermarkets. Market sales of salted sea cucumber are mostly imported from Japan. Every year, a certain number of salted sea cucumbers are imported to Dalian and Qingdao. The vast majority of sea cucumbers are transported through Hong Kong and South Korea, and the proportion of smuggled imports is relatively high. As the authorities do not hold the origin of sea cucumber, this provides space for unscrupulous traders. China's sea cucumber market provides a large number of employment opportunities for Japan.

The sixth question: Cultivated sea cucumber and wild sea cucumber is different. Is the cultivated poor?

Dr. Ding: the quality is mainly related to the environment. Different environment causes different quality. Some in open aquaculture in excellent waters are nearly the same as wild ones. But sea cucumbers' enrichment of lead and arsenic is very strong. Sea cucumbers in poor environment contain higher content of lead, which is over 10,000 times more than national standard. At present, domestic live sea cucumbers and part of dry sea cucumbers are cultivated.

The seventh question: Are dry sea cucumber easy to digest, but live ones not so? Right? Which one is better?

Dr. Ding: They are both difficult to digest. But the live ones are of higher nutritional value, because active material is retained in the body, especially high content of saponin in sea cucumbers’ scuba, casings and gonads. Therefore, live ones are better to eat.

The eighth question: It is said that sea cucumber is “ginseng in sea”. Really?

Dr. Ding: There is saponin in both sea cucumber and ginseng, which is a coincidence. Saponin is bitter, poisonous and spicy, so it is also called sea cucumber or sea cucumber toxin. Saponins of sea cucumber are the earliest animal saponins discovered by people. They have impacts on anticancer aspects and other aspects. But if you use excessive amount one time, there will be toxic and side effect. For example, excessive use of saponin can cause mouth parched and tongue scorched, even cause epistaxis.

The ninth question: Only the Chinese people eat sea cucumber, or foreigners do not eat sea cucumber?

Dr. Ding: No. In fact, Chinese people eat sea cucumber is to learn from the Japanese. 400 years ago, there was no record on the Chinese people eating sea cucumber, while over 1,000 years ago, there was the record on Japanese. Actually, Japanese and Korean have the habit of eating sea cucumbers, while European and American people scarcely eat sea cucumbers. Before introduced to China, arctic sea cucumber is mainly used as raw materials for the treatment of arthritis drug extraction or as a feed additive for pets.

The tenth question: Why are arctic sea cucumbers so cheap? Are they good to eat?

Dr. Ding: They are wild, and the costs are mainly fishing, processing and import tariffs, so they are relatively cheap. The content of saponin in arctic sea cucumbers is higher than stichopus. With moderate amount of acid mucopolysaccharide and high medical value, arctic sea cucumbers are beneficial to the elderly, cancer patients, infirm and mental workers. They are the best sea cucumbers. But they may have some kind of smell because of high content of saponin. If you don’t want to absorb too much saponin, you can remove it through soaking. (The above article comes from the Internet)