Kombu

Konbu(fromJapanese:昆布,romanized:konbu or kombu) is ediblekelpmostly from the familyLaminariaceaeand is widely eaten inEast Asia.It may also be referred to asdasima(Korean:다시마) orhaidai(simplified Chinese:海带;traditional Chinese:海帶;pinyin:Hǎidài).
Kelp features in the diets of many civilizations, including Chinese and Icelandic; however, the largest consumers of kelp are the Japanese, who have incorporated kelp and seaweed into their diets for over 1,500 years.
There are about eighteen edible species in Laminariaceae and most of them, but not all, are called kombu. Confusingly, species of Laminariaceae have multiple names inbiologyand infisheries science. In the following list, fisheries science synonyms are in parentheses, and Japanese names follow them.
Kombu is aloanwordfromJapanese.
In Old Japanese, edible seaweed was generically called "me" (cf.wakame,arame) andkanjisuch as "軍布",海藻or "和布"were applied to transcribe the word. Especially, kombu was calledhirome(fromhiroi, wide) orebisume(fromebisu).Sometime later the nameskonfuandkofuappeared respectively in two editions of Iroha Jiruishō in 12th–13th century.
Various theories have been claimed for the origin of the name kombu, with the following two predominant today.
One is that it originated from theon'yomi(Sino-Japanesereading) of the Chinese name 昆布 (kūnbù).The kanji itself already could be seen inShōsōin Monjo(8th century) andShoku Nihongi(797) in Japan, and furthermore trace back in China, as early as 3rd century, to the bookWupu Bencao(around 239).Li Shizhenwrote the following in hisBencao Gangmu(1596):
Another possibility to explain the association arises because descriptions of kūnbù in Chinese documents are vague and inconsistent, and it is impossible to identify to which seaweed the term might have applied.  For instance, Chen Cangqi (681–757) noted: "kūnbù is produced in theSouth China Sea; its leaf is like a hand and the size is the same as asilver grassand areed, is of red purple; the thin part of leaf is seaweed",which is similar to wakame, arame, kurome, or kajime (Ecklonia cava). The difficulty is that, at least in that time, kombu was not produced either in the East nor in the South China Sea.  Moreover, following Zhang Yxi, Li Shizhen classified kūnbù and haidai (stands for kombu in Chinese) as different things,and this classification continues in China today.
Although archaeological evidence of seaweed is hard to find because of its easy decomposition, some plant remains of wakame seaweed are found in some ruins of theJōmon Periodwhich leads to the supposition that kombu was also eaten at that time. As to surviving documents, the letters 軍布 (in Sino-Japanese reading 軍 is gun/kun; 布 is fu/pu/bu) appeared in Man'yōshū and wood strips from Fujiwara-kyō, and may have indicated kombu. TheShoku Nihongi(797) reports: in 797Suga no Komahiru[ja]ofEmishi(Ainu or Tohoku region people) stated they had been offering up kombu, which grew there, as tribute to theYamato courtevery year without fail. TheEngishiki(927) also reports that kombu had been offered up byMutsu.
During theMuromachi period, a newly developed drying technique allowed kombu to be stored for more than a few days, and it became an important export from the Tohoku area.By theEdo period, as Hokkaidō was colonized and shipment routes were organized, the use ofkombubecame widespread throughout Japan. TraditionalOkinawan cuisinerelies heavily onkombuas a part of the diet; this practice began in the Edo period. Okinawa uses morekombuper household than any other prefecture. In the 20th century, a way to cultivate kombu was discovered and it became cheap and readily available.
In 1867, the word "kombu" first appeared in an English-language publication—A Japanese and English DictionarybyJames Curtis Hepburn.
Umami, abasic taste, was first scientifically identified in 1908 byKikunae Ikedathrough his experimentation withkombu.He found thatglutamic acidwas responsible for the palatability of thedashibroth created fromkombu, and was a distinct sensation from sweet, sour, bitter, and salty tastes.Ikeda named the newly-discovered tasteumami(うま味), from the Japanese wordumai(うまい, "delicious").
Since the 1960s, driedkombuhas been exported from Japan to many countries. It was available initially at Asian, and especially Japanese, food shops and restaurants, and can be found in supermarkets, health-food stores, and other nonspecializing suppliers.
Kombu is sold dried (dashi konbu) or pickled in vinegar (su konbu) or as a dried shred (oboro konbu,tororo konbuorshiraga konbu). It may also be eaten fresh insashimi.
Kombu is used extensively inJapanese cuisinesas one of the three main ingredients needed to makedashi, a soup stock.Konbu dashiis made by putting either whole dried or powdered kombu in cold water and heating it to near-boiling. The softened kombu is commonly eaten after cooking or is sliced and used to maketsukudani, a dish that is simmered in soy sauce andmirin.
Kombu may be pickled with sweet-and-sour flavoring, cut into small strips about 5 or 6 cm long and 2 cm wide. These are often eaten as a snack withgreen tea. It is often included when cooking beans, putatively to add nutrients and improve their digestibility.
Konbu-chaorkobu-cha(昆布茶) is a tea made by infusing kombu in hot water.  What Americans callkombuchais called "kōcha kinoko" in Japan.
Kombu is also used to prepare a seasoning for rice to be made intosushi.
Kombuis a good source ofglutamic acid, an amino acid responsible forumami(the Japanese word used for abasic tasteidentified in 1908). Several foodstuffs in addition tokombuprovide glutamic acid orglutamates.
Kombucontains extremely high levels ofiodine. While this element is essential for normal growth and development, the levels in kombu can cause overdoses; it has been blamed for thyroid problems after drinking large amounts of soy milk in whichkombuwas an additive.
It is also a source ofdietary fiber.  Algae including kombu also contain entire families of obscure enzymes that break down complex sugars that are normally indigestible to the human gut (thus gas-causing).It also contains the well-studiedalpha-galactosidaseandbeta-galactosidaseenzymes.
Genetically manipulatedE. colibacteria can digestkombuintoethanol, making it a possible maritimebiofuelsource.