You may have heard sake referred to as “rice wine.” Perhaps this is because its alcohol content is similar to but slightly higher than wine at about 16-20%.But in fact, sake is brewed, and therefore is less like wine in the way it is made and more like beer.

Aside from the differences in ingredients, the main difference between the sake brewing process and that of beer is that beer brewing is a series of sequential steps; starch to sugar conversion followed by sugar to alcohol fermentation. With sake these two steps take place simultaneously in the same tank. This unique “multiple parallel fermentation” enables sake to have the highest alcohol content of any non-distilled beverage in the world. Making sake is a complex and even paradoxical undertaking. It is traditional and ritualistic yet always subject to tweaking and experimentation. The work done by the kurabito (brewery workers) can be both arduous and laboriously repetitive. It relies on technical, scientific, and biological expertise but is at the same time an artisanal craft practiced by intensively schooled members of centuries-old guilds. It can be highly secretive and its arcane terminology comprises a (Japanese) language all its own. Daunting? Maybe. But at the same time, these same characteristics are also what make learning about sake all the more fascinating and fun.

Most sake is made by following the steps outlined by this basic blueprint...


1) Seimai – polishing the sakamai

2) Senmai & Shinseki – rinsing and soaking the polished rice

3) Jomai – steaming the rice (creating the mushi-mai)

4) Koji – a portion of the steamed rice is mixed with koji-kin (mold)

5) Shubo (or Moto) – the yeast starter is formed by mixing the koji (steamed rice mixed with koji-kin) with steamed rice, water and yeast (kobo)

6) Moromi – the yeast starter (moto) is mixed with more steamed rice, koji, and water; this part of the process is repeated three times over four days as fermentation takes place

7) Shibori – the moromi is pressed, squeezed, or allowed to drip through a mesh

8) Roka – the pressed sake is micro-filtered

9) Pasteurization – most sake is pasteurized (subjected to heat to deactivate heat-sensitive enzymes left from the koji) twice; after brewing, before storage, and again before shipping. Sake that hasn't been pasteurized called nama-zake is fresh, lively, and bright with more pronounced aromas than regular sake. There are two types of once-pasteurized sake, nama chozo (just before shipping only) and nama-zume or hiya-oroshi (before storage only and not before bottling).

10) Aging & Storage – most sake is aged for 6 months before it is released to ensure that the brashness of the fresh brew calms down a bit and to allow the flavors to mesh.

11) Bottling

The brewing season begins in the fall and concludes in the early spring. At its outset, a ball made of vibrant green cedar leaves called a sugidama is hung over the entrance to the brewery . When the once bright green ball has turned brown, it is the signal that the sake made over the winter months is ready. You may have noticed that our logo features a stylized version of the green sugidama. When you visit us, you’ll find one hanging in our window to let you that you’ve found Sakaya!

SEIMAI
After it has been harvested in the fall, the rice is milled (or polished) using specialized machinery, to remove the fats and proteins that exist in the outer shell of each grain. Typically, anywhere from 30% to 65% of the individual rice grain is milled away depending upon the type of sake that the brewer intends to make (see Sake Classification).

SENMAI & SHINSEKI
After milling, in order to reabsorb moisture, the rice is allowed to rest for approximately two months. It is then washed and then soaked to increase its water content. This is necessary because it prepares the rice for steaming, the next step.

JOMAI
Once the rice has been rinsed and soaked, it is then steamed. There are various methods for steaming, both traditional (in vats) and modern (via conveyor belts). After steaming the rice is then cooled by spreading it out on mats or by machine.

KOJI
After cooling, a portion of the steamed rice (mushi-mai) is taken to a special room called the koji muro and used to create the koji by sprinkling it with the koji-kin (mold). This koji rice is kept warm by bundling it for a time, then spread out and mixed so that the grains do not stick together and finally put into trays (or a machine) which create(s) the uniform conditions of temperature and moisture needed for the koji kin to act upon the steamed rice. Once this has taken place, the koji is then spread out again to cool and dry in preparation for its addition to the tank containing the other elements necessary for fermentation.

MOTO
After the koji has dried, the yeast starter or moto (sometimes also referred to as the shubo) is prepared in a small tank using a mixture of water, koji, rice, and yeast. The moto is allowed to sit for about two weeks in order to generate the requisite high concentration of yeast cells needed to drive fermentation.

MOROMI
The moromi or mash is created over a four day period in a large tank using the yeast starter plus more steamed rice, koji, and water. These elements are added three times over the four days essentially tripling the size of the batch. For each addition new koji is made and the rice preparation process is repeated. The resulting moromi is then aged in the tank for 20 to 40 days all the while undergoing fermentation under strictly controlled conditions e.g. temperature, etc.

SHIBORI
At the end of the 20 to 40 days of fermenting in the tank, the mash is (usually) pressed or squeezed through a mesh to separate the sake from the solids precipitated during fermentation (sometimes referred to as lees, dregs, or sake kasu). Shibori (pressing) may take several forms depending upon the scale of the brewery’s production and/or whether more traditional, artisanal methods are favored:

Pressing the moromi with a large accordion-like machine called an assaku-ki. 99% of all sake is made using this method.

Fune Shibori, used to produce better quality sake, is the more traditional, gentler method of pouring the moromi into long cotton bags and then placing them in a long box called a fune. The first third of the sake to seep out of the bag and drain out through the bottom of the fune is known as arabashiri or “first run” which is often released and drunk early in the Spring. The second third, which results from pressure exerted by piling the bags on top of each other in the fune, is called nakadori. This is usually the best quality sake of the batch. The final third of the sake is induced by gently applying pressure to the bags with a flat lid is the seme.

Shizuku, the most time intensive method that produces even better sake, actually doesn’t involve pressure at all. It simply lets the long bags to hang and allows gravity do the rest as the sake slowly drips through.

Many brewers take a portion of the shiboritate or just-pressed sake, bottle it and release it without aging for public consumption. It has enjoyable uniquely young, brash flavor qualities as you might expect.

PASTEURIZATION, AGING, & STORAGE
After pressing, sake is usually pasteurized before aging in storage for about six months, micro-filtered, is diluted with water to adjust the level of alcohol, bottled, then pasteurized again before shipping. The order for this process is not necessarily the same for any two brews and there are additional intermediate steps possible or steps that are eliminated, depending upon the type or style of the sake to be produced.

For instance, not all sake is pasteurized twice. Namazake (draft sake) is unpasteurized and therefore must be kept refrigerated at all times. There are two other varieties of Nama; Namachozo which is not pasteurized before storage but is before shipping and Nama-zume or Hiya-oroshi which is pasteurized before storage but not before shipping.

Another variety of sake is Genshu meaning that no water had been added. In other words, the level of alcohol at the end of fermentation is unadjusted. Yes, that means that these nihonshu have a bit more punch to them!

To get an idea of how varying the process produces different types of sake, have a look at this diagram.

Just-Pressed Sake > Pasteurize > Store > Filter > Add Water > Pasteurize > Bottle > Regular Sake
Just-Pressed Sake > Filter > Add Water > Bottling > Namazake
Just-Pressed Sake > Store > Filter > Add Water > Bottle > Namachozo
Just-Pressed Sake > Pasteurize > Store > Filter > Add Water > Bottle > Namazume
Just-Pressed Sake > Pasteurize > Store > Filter > Pasteurize > Bottle > Genshu
Just-Pressed Sake > Filter > Bottle > Nama Genshu


As noted in Understanding Sake, there are an infinite amount of variations made to the process, the result of which is a larger universe of tasty brews for us to enjoy!