The Sake-Brewing Process (Part 1)

The many steps of the sake brewing process are so inter-related, yet with each one constituting a universe unto itself, it is close to futile to try to put it into a few words. But we must try and the simplest of overviews would look something like this;

Steamed rice and koji (rice cultivated with koji mold, technically known as aspergillus oryzae) are first mixed with yeast to make a yeast starter, in which there is a very high concentration of yeast cells. After that, more rice, koji, and water are added in three batches over four days. This mash is allowed to sit from 18 to 32 days, after which it is pressed, filtered and blended.

This would be enough to get you through most conversations. But let us look at the process a bit more closely. Here are the main steps and processes:

Rice Milling
After proper sake rice (in the case of premium sake, anyway) has been secured, it is milled, or polished, to prepare it for brewing good sake. This is not as simple as it might sound, since it must be done gently so not too much heat is generated (which adversely affects water absorption) or not crack the rice kernels (which is not good for the fermentation process).

Washing and Soaking
Next, the white powder (called nuka) left on the rice after polishing is washed away, as this makes a significant difference in the final quality of the steamed rice. (It also affects the flavor of table rice; try washing your rice very thoroughly and notice the difference in consistency and flavor.) Following that, it is soaked to attain a certain water content deemed optimum for steaming that particular rice. The degree to which the rice has been milled in the previous step determines what its’ pre-steaming water content should be. The more a rice has been polished, the faster it absorbs water and the shorter the soaking time. Often it is done for as little as a stopwatch-measured minute, sometimes it is done overnight.

Steaming
Next the rice is steamed. Note this is different from the way table rice is prepared. It is not mixed with water and brought to a boil; rather, steam is brought up through the bottom of the steaming vat (traditionally called a koshiki) to work its way through the rice. This gives a firmer consistency and slightly harder outside surface and softer center. Generally, a batch of steamed rice is divided up, with some going to have koji mold sprinkled over it, and some going directly to the fermentation vat.

More to come
There are many other steps involved in brewing sake that will be covered in future posts. If you would like an even more in depth look at brewing sake take a look at the Sake Production Slideshow, an indispensable tool to visually understand how sake is made.

Explore posts in the same categories: Sake brewing

Tags: john gauntner, koji, rice, rice milling, sake, Sake brewing, sake education, sake slideshow, sake world, steaming

You can comment below, or link to this permanent URL from your own site.