When sake is crafted using highly polished rice (at least half of its original grain weight), it can be labeled as the highest grade: Daiginjo.
To create our flagship Dassai 23, we polish the rice down to remove 77% of its outer surface until only a tiny core of the rice remains.
Rice washing & soaking
Following the polishing process, which can takes up to three to four days and nights, the rice undergoes a washing process in which water content is controlled in increments of 0.1%.
The reason we are able to control the water content of the rice so precisely is because we hand-wash the rice.
Koji rice making
The koji making is the most important task in sake crafting: an experienced, skillful person is essential.
The overall condition of the rice has to be checked at all times so we could manipulate the koji making process in consequence: at times delicately and sometimes roughly.
At Asahi Shuzo, we use a long, low-temperature fermentation method. Because yeast is viable, even a slightly elevated temperature can activate it. Meanwhile, careful fermentation at a temperature so low that it is only marginally life-sustaining for the yeast to make the resulting sake smoother, and with richer aromas.