Up and coming Shizuoka Hiraki Sake Brewery was established in Shizuoka in the early 20th century. It moved to Okayama prefecture in the mid 20th century but to honor the founder’s birthplace, they opened a second brewery in Shizuoka in 2012.. The production volume is just 100 koku,so it is one of the smallest sake breweries in Japan, focusing on their passion for sake in every single tank.
In the Shizuoka Hiraki Sake Brewery, there are two key people involved in making the sake. Toji ,Mr Kuya has over 20 years’ experience in sake production in Okayama. Mr Totsuka is a direct descendant of the founder studied sake production at Tokyo Agricultural University, widely regarded as the best university for these studies. Their sake production is a well-balanced combination of Kuya’s experience and Totsuka’s scientific approach.
Sake Experience Japan interviewed Mr Totsuka about the new Shizuoka production.
According to Mr Kuya, the move was not as simple as transferring the Okayama techniques from Okayama to Shizuoka, but also required adjustment to adapt to Shizuoka’s environment. Since Shizuoka boasts great yeast (aptly called “Shizuoka yeast”), Shizuoka Hiraki Sake Brewery has high hopes for the outcome of Shizuoka yeast in future production.
Before re-establishing the brewery, they needed to dig 50m underground to find the ideal water. The water source is the underground water of Abe river which has run for over 10,000 years. They first use this water for the important process of washing and soaking, according to Mr Totsuka’s precise call. He strictly measures the time with meticulous care, down to the second because the water absorption decides the quality of koji and kakemai, which is essential in determining the quality of the final product. After soaking and again after steaming, they measure the weight of every single batch and adjust the time for future batches if needed.
At Shizuoka Hiraki, they allow kakemai water absorption to be 7% less than kojimai (steamed rice for koji production). If kakemai has more water, it tends to be dissolved easily. Even though the rice is polished and the outer part is removed, it still contains some lipids and protein. If the rice is dissolved more than ideal, it gives off-flavors. Additionally if kakemai is dissolved faster, the percentage of sugar in moromi increases too fast and the increased osmotic pressure kills the yeast, leading to a fermentation / saccharification imbalance. For these reasons, they adjust the more common absorption ratios to ensure that the steamed rice suits their purposes.
Like other breweries, they take good care of their koji production process. Approximately one week before making koji, they start heating up the koji room to 38 – 40℃. After steaming and cooling the rice, they pull the steamed rice into the koji room until the temperature of the steamed rice reaches around 31℃. Then they start sprinkling koji on the steamed rice.
When koji propagates, it generates heat. The temperature is reduced when water in the mix of steamed rice and koji is released. So temperature is controlled by the balance of these two actions.
Around 35℃ is called the “devil temperature zone” because it is conducive to production of unwanted enzymes. For this reason, brewers do their best effort to maintain the temperature at 43℃ (ideal for koji to produce the desirable enzymes) and escape the risky 35℃ temperature zone as quickly as possible.
Initially, the water absorption of the steamed rice is around +41%, but it goes down to around +30% during koji propagation. During this time, the toji checks the koji quality through the night to achieve the ideal quality.
The production process progresses from koji propagation to fermentation in moromi, then pressing. It takes almost a day to press moromi, so they control the temperature around 5℃ to keep the aroma and avoid oxidization caused by higher temperatures.
This young sake brewery takes good care of all procedures with a passion and achieves outstanding final quality.
Mr Kuya and Mr Totsuka are united in their sake production philosophy that their sake should go well with food. For a long time, sake was intended to drink like water, so sake making increasingly produced sake is drinkable and not interfere with the taste of food.
However Shizuoka Hiraki sake tends to have relatively more body compared with most other Shizuoka yeast sakes. They try to extract the rice’s umami and hold sophistication and also fresh acidity, making it “food friendly”. This sake can therefore go well with food and enhances the meal.
In 2017, Shizuoka Hiraki sake has received the Chairman’s Award at Shizuoka-Shinshu (new sake) Kanpyokai competition in 2015, 2016 and 2017. This commendation is an early indication of their anticipated future success.