Feb 19, 2010

Koji Rate Regulation of Regular Sake

Lately, we have colder days than in the average February here in Japan. I prepared for little birds some apple on a stick which was tied to a branch of a tree in the garden. It took several days for them to find there was their food. Finally, white-eyes came to the food and enjoyed their meal. The following is the movie I took yesterday morning:

Well, in this post, I discuss the koji rate regulation, which is currently applied to tokutei-meisho-shu, or special designation sake, and may be going to be introduced also to regular sake. Whether to apply the koji rate regulation also to the regular sake is likely to be discussed by Japan Sake Brewers Association (source: in Japanese).

The koji rate of a specific sake represents the percentage of the koji rice (rice malt) used for making the sake to all the rice (including the steamed rice) used.

The tokutei-meisho-shu must have the koji rate of 15% or higher value as a standard. However, there is no koji rate standard for the regular sake so far.

By lowering the koji rate, brewers can reduce production cost and offer low-priced regular sake. However, lowering the koji rate probably requires the addition of enzyme, which helps the saccharification activity.

As it has been said "koji first, yeast starter second, and fermentation third," koji making is considered to be the most important process in sake making. If regular sake is made by using only a little amount of koji rice, the output from this most important process, is such sake considered authentic? This question may partly have lead to the movement of the koji rate regulation of the regular sake.

However, major breweries, which are making low-priced sake in large quantity, seem to be reluctant to support introduction of koji rate standard for the regular sake.

I would feel like I were deceived if someone had me drink sake that used only little amount of koji rice or no koji rice while saying "this is sake." It is important that consumers are well informed of what ingredients and additives are used.

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will said...

Ichibay, I have no background knowledge about the koji rate regulation. Will you give me a quick tutorial so I can follow the issue in the post?


Ichibay said...

Dear will,
Thank you for being interested in my post.
As I described in the post, koji rate is the percentage of the koji rice (rice malt) used for making the sake to all the rice (including the steamed rice) used.
For example, if a brewer uses 150 kg of steamed rice and to make koji rice, while he/she uses 850 kg of steamed rice as-is for preparing yeast starter and fermenting mash, the koji rate of the sake will be 15%.
Koji mold on the koji rice produces enzyme that converts starch in rice into sugar (saccharification), which is then decomposed into alcohol and carbon dioxide gas by yeast. So, if the koji rate is low, the enzyme is not enough and saccharification by the enzyme does not occur sufficiently. To supplement the shortage of the enzyme, the brewer may add artificial enzyme (or somethng that functions similarly to the enzyme) to the yeast starter or fermenting mash.
Don't you think "sake" made without using koji rice is like "beer" made without using malt?
Does my explanation help?

WillAuld said...

Ichibay, Yes this helps. So the gov. taxes based on the %koji/totalRice (the koji rate).

What is the tax level?

Oh, and I want real sake!

Ichibay said...

The tax rate of sake is 120 yen per 1 litter regardless of the koji rate.
Using koji rice in the making process of alcoholic beverages is quite characteristic of sake. So, I think a genuine sake must have a certain level of koji rate.

WillAuld said...


I have been thinking that you were talking about a tax being imposed where the tax was call the "koji rate" but now I see that it is literally a requirement on the ingredients themselves.

I am, in general, not for regulation. If the low koji rate sake is not very good then people who care will not buy it. I don't think I have had sake made this way, so I don't know how it might taste differently from "standard" sake.

German's have Reinheitsgebot which is an ingredient requirement for beer that says only grain, hops and water can be use. If others lived by this standard we would not have the wonderful Belgium beer for one.

Have your had "sake" made using an enzyme substitute?

Ichibay said...

I am also not opposed to the enzyme regulation but I think consumers need to be informed of what is used for making sake they are drinking.
Currently, whether an enzyme is used for making sake or not is not displayed on the sake label. So, I am not sure I have ever drunk such sake. But I have drunk a lot of kinds of sake, and some of them may have been made by using an enzyme.