Sake secrets at the Gekkeikan brewery

In February 2017, Sakagura London bar manager Zdenek Zemen and Kinu Yukawa from Japan Centre took  2016/2017 Gekkeikan Sake Cooking Competition winner Tom Wilson on an apprenticeship at the Gekkeikan Sake School in Fushimi, Kyoto, Japan – for a glimpse at the sake making experience. Read on to find out how sake is made at one of the world’s oldest sake companies.

Translation: It has been passed down generation after generation by the kurabitos

In the brewery, apprentices live by 5 main principles:

First and foremost, to respect the harmony amongst each other.

Stay healthy and positive.

Never cease to research: listen to the malt.

Improve your skills: always examine oneself.

Keep clean and tidy:  always think safety first.

The hands-on course was housed in Gekkeikan’s Uchigura Sake Brewery, the old brewery which was built in 1909.  The course was taught by Mototsune Aikawa Toji, the master sake brewer, who manages the project of sake making at the Uchikura.  Aikawa Toji brings with him, a wealth of sake making experience and scientific principles.  Gekkeikan sake benefits from the purity of the gentle spring water of Fushimi. Fushimi meaning ‘hidden water,’ describes the underground spring water which contributes to the extremely smooth and mellow sake of Gekkeikan.

Each morning started with the daily ritual of paying respect to the shrine. A small shrine is set up at the brewery where each morning the kurabitos (sake brewers) worship and ask for the blessing to brew good sake safely. As rice is the most important ingredient of sake making, it is placed at the centre of the shrine as the most precious offering.

Milling of the rice 

Aikawa Toji had prepared 100kg of Yamada Nishiki rice from Hyogo prefecture, which was milled down to 50% for the apprentices to wash and steam.  Premium sake is called Ginjo where the rice is milled by more than 40%.  Super premium sake is called Daiginjo where the rice is milled by more than 50%.  With this project, the apprentices made Junmai Daiginjo, a very special version of sake only available at the Gekkeikan Okura Sake Museum.  

Rice washing process 

The rice washing and steeping process is a very important process of sake brewing.  10 batches of 10 kg rice were divided and manually washed in a large basin in teams of two. The rice was washed as the apprentices sang an ‘Ichi-Ni Ichi-Ni (one-two one-two) rhythm tune.  The rice bran was washed away and the rice left to steep in fresh water until the water absorption reached the desired quantity.  

Rice steaming process 

The washed rice was then steamed for about an hour in a ‘Koshiki,’ or giant steamer. Once the rice was steamed, it was then cooled down to room temperature. The 100 kg of rice then turned into 140 kg of rice. 20% of the total amount of rice was then removed to the make the koji. Koji is a type of fungus normally grown on rice or soybeans, it is used as a fermenting agent and is at the heart of the whole sake brewing process. The rest of the rice was then cooled down to 5-10 °C for fermentation.  

Aikawa Toji then took the apprentices to the Koji-muro (koji incubation chamber), the room temperature adjusted room to make koji. Koji-making is a two-day process and the koji must be checked every two hours.

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San Dan Jikomi Stage 

For the main sake fermentation stage – the Moromi making; water, koji and rice were added to the large tank in stages. When the yeast activity is high, the foam comes up to the surface.  The activity of the yeast gradually decreases, and when the foam’s surface turns flat, the fermentation is complete.

At the final stage the main mixture is almost solid and while fermentation continues, the rice dissolves and turns into a liquid.  The main fermentation is performed at a low temperature because the quality of sake is improved by low-temperature fermentation.  The fermentation takes approximately 30 days.

The Gekkeikan Sake Koubo Junmai Daiginjo, the sake the apprentices made, will be shipped to London next month.