The rice is milled down to the center of the grain. The quality of the sake increases as the outer portion is removed, as the outer portion contains components that cause undesirable flavors and aromas.
The rice is left to dry in a cool and dark place for two to three weeks to lower its temperature and to level the water in the grains.
The rice is washed to remove unwanted impurities such as rice bran and crumbs.
The rice is soaked in a tank to prepare for the steaming process. The duration, temperature, and conditions under which the rice is soaked plays a large part in determining the quality of the resulting product.
The rice is steamed to the extent that is firm outside, and soft inside.
The rice is cooled to different temperatures to create the components necessary in the later stages.
Mold is cultivated on a portion of the rice in order to catalyze the release of enzymes made possible through the breaking down of starch.
The yeast starter, or the shubo, increases the amount of yeast. This is created by mixing Koji-rice, steamed rice, water, and yeast. Lactic acid is either produced, or introduced, and is useful in preventing the growth of undesirable bacteria.
The fermenting mixture is created with the Koji-rice, the remaining rice from the cooling process, known as Kake-rice, the shubo, and water. This mixture is known as moromi.
The moromi is pressed to separate the sake from the residue.
The sake is stored to allow it to age and mellow.