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About Iwanoi

Said to have been founded in 1723, the company has been passed down from generation to generation as a subsidiary business of the head of the family. The brewery has been engaged in full-scale production of sake since the Taisho Era (1912-1926) and in 1947 won the top prize in the National sake Competition.
The current representative, Yoshikazu Iwase, is the 11th-generation company head.
His predecessor, Sadayuki(deceased), was a photographer who had been taking pictures of ama (female shell divers) since before World War II and won the "Prime Minister's Award" at an exhibition sponsored by the Mainichi Newspaper.
(Representative work: "Groups of Female Shell Divers," a collection of photographs)

The beams of the thatched-roof main structure are made from the mast of the San Francisco, a Spanish galleon shipwrecked off the coast of Onjuku in 1609.
A galleon ran aground off the coast of Onjuku and many of its crew washed up on the beach. The name of the ship was the “San Francisco.” The 373-member crew, headed by Don Rodrigo, who had completed his term as provisional governor of the Philippines, were on their way from the Philippines to New Spain (Spanish Mexico). Fifty-six of them passed away, but the remaining 317 were rescued by the villagers of Iwawada (now Onjuku-machi). It is said that the villagers showed great sympathy for the victims, and female shell divers warmed their frozen bodies and revived them. They generously provided them with their husbands' clothes and food, which led to the establishment of amity between Japan, Spain, and Mexico. Four hundred years have passed since the time of Tokugawa Ieyasu.

Dedication to sake Brewing (Yamahai -- sake brewing using natural yeast and no mashing -- and Koshu -- matured sake)

About 10 minutes away from the brewery is the Onjuku coast, called "Tsuki-no-Sabaku” (Moon Desert).
Because of its proximity to the coast, the brewery's brewing water passes through the seashell layer of underground water, which has a "hardness of 13-15," one of the hardest in Japan.
High calcium and magnesium content means high nutrient content and vigorous fermentation. By using the hard water and our "Yamahai yeast" method of brewing, we can produce sake with a rich, mellow flavor and strong acidity.
In order to bring out the flavor of rice, which is one of the unique characteristics of Iwanoi's sake quality, we are adamant about using "Yamahai brewing" and brew more than two-thirds of our total volume of sake with "Yamahai brewing.”
With the exception of Daiginjo, most of the rice utilized is grown in Chiba Prefecture.

After the brewing process is completed in early spring and the new sake is ready, it then goes into storage, referred to as the "second brewing process.”
The roughness of the new sake will stay with it through the summer and then become calm sake in the fall. After a lengthy period of over one or three or five years, or even over ten, twenty, and thirty years, it becomes koshu or matured sake.

Iwase Sake Brewing Co.,LTD. has been brewing Ginjo-shu sake since 1930 and has won many awards.
The sake entered in sake competitions was intended for technical improvement and was not sold, unlike today. The sake simply remained in storage at the brewery.
Ten years later, when we tasted the sake, we found that it had a different color from new sake, as well as a gentle and pleasantly intertwined aroma, a wide range of umami, and had transformed into a wonderful, mellow, full-bodied sake.
After that, it was stored in small amounts, and from the 1960s onward, it began to be stored in a full-fledged systematic manner, which has continued to the present day.
“Iwanoi Koshu matured sake" enriches the soul.


IWANOI was founded in 1723, and has been known as one of best saké breweries among saké enthusiasts for its quality and taste.
Unique terroir and the unwavering spirit of the dedicated brewers have allowed traditional saké-making to ¬reach new heights.

In 1947, IWANOI was honored "The Best of Saké Award in Japan" and has since been selected as a favorite by many saké lovers and celebrities.
This included former French Prime Minister Jacques Chirac who enjoyed IWANOI at "The World Culture Grand-Prix Award Ceremony" and later requested bottles to be sent back to France to be shared with his friends, as well as former US President Ronald Reagan who brought back IWANOI as a memory of Japan.

In 2016, IWANOI was distinguished as a prestigious top-rated saké in Japan, by world-renowned wine critic Robert Parker.


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