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The summer in Japan is extremely hot and humid. Before the introduction of air conditioner or ventilator, it was difficult for the elderly and the sick to spend summer days without problems. Since the ambulance could not be counted on, many people died in Edo (today’s Tokyo) in July, August and September. At that time, some stores earned a lot of money in summer, selling “Ama-saké”.

(Gion Seitoku"Beauties Cooling at a River Bed" owned by itabashi art museum)
(Gion Seitoku”Beauties Cooling at a River Bed” owned by itabashi art museum)

Infusion to drink

Ama-saké is characterized by natural sweetness. More than 20% of Ama-saké consists of glucose. This glucose is produced naturally by Koji enzyme. Ama-saké contains natural vitamins such as vitamin B1, B2, B6, biotin, pantothenic acid in abundance. The assimilation ratio of these vitamins is more than 90%. The natural vitamins are stable and assimilate soon, but unfortunately it cannot be produced artificially. The natural vitamins in Ama-saké are produced by Koji-bacteria during the fermentation process.

The Koji-bacteria also produce almost all the amino acids necessary for human body by breaking down the protein from the surface of rice. Thus, Ama-saké is composed of the same ingredients as the infusion in the hospital. It is for this reason that Ama-saké is called “infusion to drink”. Although the name contains “Saké,” it does not contain any alcohol different from ordinary Saké.


Here I’d like to introduce “Ama-saké” produced by Échigo-miso-jyozou, because of its quality of rice and rice-Koji. Since Ama-saké is 100% rice drink made from only rice and rice-Koji, their quality is extremely important. With the history of more than 240 years, the ferment house of Échigo-miso-jyozou equipped with artisans and bacteria that cannot be found in modern factories.

The rice used in this “Ama-saké” is called “Hi-En-Mai”. “Hi” means flying. “En” means swallow. “Mai” means rice. This rice is produced in the town called “Tsubame” which means swallow in Japanese. “En” and “Tsubame” are different pronunciations for the same Chinese character (Kanji). Most Kanjis can be pronounced in several ways. 
The Kanji for swallow is as shown to the right. As you can see, it’s ideographic.


In Japan, the swallow has been protected as a beneficial bird since early times, because it eats pests. It’ also considered as a symbol of prosperity, because it prefers to stay among people and occasionally makes its nest at human houses. The nest is treated as a talisman and handled with care even after the swallow’s family left it.


Below are good bacteria representative:

lactic acid bacteria which produces cheese, yoghurt, etc.
 acetic acid bacteria which produces vinegar
yeast that produces bread
bacillus subtilis natto which produces “natto”.
aspergillus oryzae (Koji-bacteria) which produces Koji.


Koji is extremely important in Japanese food culture, because without Koji, most of the Japanese seasonings cannot be made; Soybean paste (soy sauce), Saké and so on.

Koji-bacteria release a large amount of enzymes out in its process of fermentation and these enzymes bring various gifts to human being. The enzyme consists of protein. Although it is inanimate being, it can compose and decompose substances. The enzyme produced by Koji-bacterium is amylase that breaks down starch into glucose, the protease that breaks down protein into amino acid and the lipase that breaks down fat into fat acid. The enzyme used in digestive medicine is mainly produced by cultivating Koji-bacteria.

There are two Chinese characters that mean Koji: 麹 and 糀.
The character 麹 was introduced from China in the 8th century. 麦 means wheat. In China, wheat is widely used to make Koji.


On the other hand, the character 糀 was invented in Japan at the end of the 19th century. We can find 米 (rice) in this character. Rice is widely used to make Koji in Japan. 花 means flower. When the rice is fermented and becomes Koji, it looks like flowers. This character is used only for the Koji made of rice.