Kombucha, which literally means kelp tea, is a type of drink which is made from dried and powderd kelp, and drank by pouring hot water. The taste is more of a soup rather than tea. Sometimes, it is seasoned with salt, or arare, bite-size rice cracker, and gyokuro, shaded green tea, are added. When shredded and freeze-dried and plum is added, it is called ume-kombucha, ume meaning plum. Ume-kombucha is often served for auspicious occasions, such as new years, as a custom.
Kombucha is not only used as a drink, but some people use the powder as seasoning for cooking, instead of using soy sauce in order to reduce the salt content. Kombucha is also good for health. For example, component contained in kelp can suppress the neutral fat level, and the elevated blood glucose level. There is also an effect to prevent high blood pressure, because it contains lots of potassium, magnesium, and can suppress the intake of salt into the body by expelling salt outside the cell.
It is not sure when kombucha was first created, but it is believed that it existed in the Edo period (1603-1868). People poured hot water in shredded kelp and drank the soup, and ate the leftover kelp after drinking. The powder type kombucha was first introduced in 1918 by Umazo Fujita, the founder of Gyokuroen tea company. Freese-dried instant coffee was first sold in 1938, so powdered kombucha was the first instant drink introduced in Japan.