In honor of National Sake Day and as part of our new Inside the World of Marussia Beverages USA hub-site launch, we had the chance to interview Kimio Yonezawa of Akashi-Tai Sake Brewery. Yonezawa is the President and Toji, or brew-master, of the company and has an impressive amount of knowledge and stories. Today, he shares a little about the unique process of Sake production and a fun cocktail utilizing both his Sake and Gin.

You take a lot of pride in the raw ingredients you use in your Sake, could you tell us a little more about this?

I am sourcing only local ingredients for my Sake so I can see the process and growth of these raw materials. For example, rice.

There are broadly two varieties of rice: indica, a long-grained variety, and japonica, a short-grained variety. Each of these can further be subdivided into sticky and non-sticky rice. Non-sticky japonica rice grown locally is used to brew sake in Japan. This is the same type of rice that Japanese people normally consume as daily food. Many types of premium Sakes are made with Sake rice which is especially suitable to sake brewing. Features of Sake rice are larger grains, lower protein content, and higher solubility during the brewing process.

The main rice variety we used is called the king of sake rice “Yamadanishiki”. It was introduced in 1924 at the local Akashi Agricultural Experiment Station and was named “Yamadanishiki” in 1936. These days it can be cultivated outside of the Hyogo prefecture too. However, we have much deeper attachment to the Hyogo-made Yamadanishiki rice as it locally grown, and it is the birthplace of this rice. Therefore, we purchase “Yamadanishiki” made in the Hyogo prefecture from a local farmer and use it for our Sake brewing. We take great pride in the locally harvested rice produced over our long history.

Your Daiginjo Genshu must be watched over for 72 hours straight—what goes on during that time, and how on earth do you stay awake?

This question needs to be explained a little more in depth!

What we need 72 hours is “Koji-mai” = Rice Koji making, for our Junmai Daiginjo / Daiginjo Genshu.
For wine making, grape juice contains sugars, which ferment in the presence of yeast, but with beverages made from grains, such as Sake and beer, it is first necessary to create the enzyme to use the power to break down the starch in the grain to convert it to sugar before yeast fermentation. The enzymes play a number of roles, finely shredding the starch to convert it into sugar, breaking down protein, and producing peptides and amino acids.

In beer brewing, malt is used as the source of these enzymes, but for making Sake, a substance called kome-koji (Rice Koji) is used. Rice Koji is made by cultivating koji-fungi on steamed rice. Rice koji may simply be called koji. The koji fungus (Aspergillus Oryzae) is a beneficial and safe variety of mold that is also used in the production of traditional Japanese seasonings, such as miso and soy sauce. The first step in making the koji used in sake brewing is to inoculate steamed rice with the spores of koji-fungi, called tane-koji.

After a while, the spores germinate and start to spread their fungal filaments. In about two days, the steamed rice is entirely covered with koji-fungi. As the koji-fungi grow, they produce enzymes, which accumulate within the koji (Fig. 2.4). Koji-fungi are most active at a temperature of around 96.8°F, but cease all activity at a temperature above 113°F. For this reason, the process is carefully controlled in a room in the brewery called a “koji-muro”, where the temperature is kept at around 86°F and the relative humidity maintained in the range of 50%– 80%. The polished rice to make koji is called koji-mai. Koji enzymes are highly efficient and the ratio of koji-mai in the polished rice used to make sake only has to be in the 15%–25% range for the enzymes to perform their role.

Currently, we use the temperature sensor and receive a notification email when the temperature is likely to exceed 113 °F even at night. That is the reason making Koji is long process and lots of time and attention needed to be devoted. This process is one of the most sensible process in Sake making. These days. We can monitor the temperature of Koji making so we check only when it is needed if temperature is too low or high and go back to the brewery to take care of the Koji. In the older days it had to be monitored all the time but nowadays we are helped a little by technology, as temperature can be monitored so we only wake up when needed.

Along with Akashi-Tai, Kimio Yonezawa also leads 135 East Gin and Hatozaki Japanese Whiskey. The elegance and history of Sake brewing can be seen through the expressions of both other Spirits, making them a perfect way to explore the possibilities of Sake.

Longitude Line

1 oz. 135° EAST Gin
1/3 oz. Akashi-Tai Umeshu
1/3 oz. Hibiscus Syrup
1/2 oz. Fresh Lime Juice
1 oz. Egg White or Aquafaba*

Preparation: Dry shake (no ice), then shake with ice. Garnish with dried hibiscus flowers

Aquafaba* – brine or water from chickpeas used as a substitute for egg whites. Often used in vegan baking/cooking.

Make sure to check back in later this month for our full interview with the enigmatic Kimio Yonezawa.