The article and photos by Fumiko Koike 

In the last article, I talked about :

Essential information about Japanese sake 

This time, I would like to answer the following frequently asked questions about Japanese Sake. 

 Contents:

(1) Why do you have to remove the surface of rice grains?

(2) What are main ingredients?

(3) How is sake made?

(4) Are there any other types of sake or any by-products?

It is to remove unnecessary things for sake brewing such as lipid and protein which can make unfavorable taste in sake. 

The more you mill, the smaller and more fragile the rice grains will become.  Some traditional breweries do this process manually in order NOT to break the grains. Generally, Daiginjo-shu is the most luxurious for that reason.

There are some other factors that can affect the taste such as : the quality of water, the kind of rice, the amount of water added, whether it is pasteurized or not, the climate and so on. 

Basic ingredients are as follows ;

1.  rice for sake brewing (Specialized varieties of rice for sake are used. They are larger than table rice.)

2.  water

3.  two kinds of fermentation agents  - ' Koji mold (Koji spores)' and ' Kobo (yeast)' 

・The Koji is used to saccharify starch in the rice.

・Kobo produces alcohol.

First, polish (mill) the brown rice until you get the target percentage of rice weight remaining.

Next, the rice is steamed and usually divided into three portions.

Sprinkle the first portion of steamed rice with the Koji mold to make the Koji malt.  

Add the Koji malt, Kobo yeast, and water to the next portion of steamed rice to make the seed mash called 'Shubo'.

Lactic acid can be added as well.  At that time, some long-established traditional sake breweries use lactic acid which naturally inhabits in the brewery's cellar. In that case, they do not use one sold at a shop.

Add the Koji malt, the remaining steamed rice and water to the Shubo (seed mash) in usually three stages.

This preparation of brewing in three stages is called 'Shikomi'.  Some brewers do Shikomi in more than three stages.

At this point, the Shubo (seed mash)  changes its name into 'Moromi', meaning 'the main fermenting mash'.

The alcohol fermentation lasts about one month. 

After about a month, the alcohol content of sake comes to about twenty percent.

It will be filtered and water is added to lower the alcohol content to fifteen to sixteen percent.

'Doburoku' is unfiltered sake.

'Nigori zake' is coarsely filtered sake.

'Sake kasu' is sake lees, the white residue remaining after Moromi (main fermenting mash) is being squeezed thoroughly. 

Sake kasu is used for Japanese cooking.

'Nama zake' is unpasteurized sake, and it is especially popular when a new brew of sake is started to be sold.

'Junmai shu' is sake made without added alcohol.  Reasons for adding the alcohol for brewing include :

to prevent the deterioration of sake and to add a refreshing taste to sake.

'Nama chozo shu' is raw stored for a while and pasteurized just before shipping.

'Genshu' is pure sake or undiluted sake, as water is not added after filtering.

'Nama genshu' is unpasteurized nor undiluted sake.

I hope you will enjoy the process of tasting different types of sake if you are interested and have an opportunity! 

Related article:

Essential information about Japanese sake

The article and photos by Fumiko Koike