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SAKE KNOWLEDGE

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Alcohol of Japan “Sake”

Sake is a fermented alcohol, same as wine and beer, made of rice.
Sake has played an important role in Japanese culture, and it is one of the crucial element in Japanese culinary culture “Washoku”, or even more important independently.
When you talk about Sake, it is about rice, about water and about fermentation technique inherited over years.
In this knowledge, you will find out fundamental information to understand about Sake and its composition materials.
With this information, please feel and enter the world of Japanese Sake culture.

 

Brewing process

As sake is made of rice, which is a grain, its brewing method is quite different to the other fermented alcohol.
The basic technique used in the brewing process is mostly the same for 100 years, but some of the process is now much efficient because of the invention of machinery and development of science.
In this section, you can find how sake is brewed in today’s world.

 

Polish rice

When breweries buy rice it is brown rice, so needed to polish it up.
By how much they polish rice, it change the class of the product and brewing process.

 

Wash polished rice

After polishing rice, it is required to wash up to remove any noise.
Water used in this process soak into rice, so the quality of water is important from this process.
After washing process, leave rice in water to let it absorb water slightly to make steam rice well.

 

Steam rice

Steam rice with a traditional instrument called Koshiki
By steaming rice, it optimises starch for the fermentation, balances the level of water in rice, and pasteurise for its hygiene.

 

Make rice koji (Seikiku process)

Koij convert starch in rice into glucose, and this process decides how the fermentation will be.
Put koji seed to seamed rice and let it develop for 50 hours.
It is quite difficult to switch to machinery, so brewers monitor the rice koji for 50 hours continuously to maintain the quality.

 

Make yeast mash(Shubo, Moto)

With new rice koji, it mix with steam rice, water and yeast to make Shubo or Moto which is a base of sake.
Mashing rice in the tank and develop lactic acid bacteria, which remves the noise in Shubo.
This mashing process is called Yamahoroshi and there are 3 types of Shubo.

  • Kimoto 生酛
    Traditional Shubo. Develop organic lactic acid bacteria in Shubo and use Yamaoroshi process
  • Sokujomoto 速醸酛
    Add lactic acid bacteria instead of develop naturally. It is a main stream in recent sake brewing due to its efficiency.
  • Yamahaimoto 山廃酛
    No Yamaoroshi process used. It takes more time, but produce more amino acid at the end.

 

Make moromi

Add more rice koji, water and steamed rice in Shubo and ferment it for about a month.
In this process, it is required to add them not at once, but three times separately to ferment gentle and slowly.
After this process, what we get is called Moromi.

 

Press and squeeze fermented moromi (Joso process)

After the fermentation period, now it is the time to squeeze out liquid from Moromi.
Traditionally this process is done by an instrument Fune, but these days breweries use squeeze machine.
For high end products, brewery do not even squeeze and collect drops by hanging sake in a bag.

 

Filter squeezed moromi

After squeezing process, it is required to filter to balance its aroma and avoid coloring.
Some products do not filter, so the taste is truly reflect the umami of rice, but this kind of product goes off faster.

 

Heat sake to pasteurise

Filtered sake is heated and pasteurise to keep the quality as long as possible.
Some products do not pasteurise. So you can taste genuine taste, but it also goes off faster.

 

Blend sake and add water

Before bottling, breweries blend other sake, such as previous vintage sake, to maintain taste of the brand.
To control the alcohol contents, they add some water as well.

 

Bottling

At the last, it is bottled to store and deliver to clients.
Nevertheless some breweries do not store in the bottle, in tank.
When they let sake rest for a bit it smoothen the sake taste and the way of resting differ by breweries.

 

Class

In the brewing process, there are a lot of ways to produce sake and with different method of brewing there is a different class of category in the sake market.
You can find classification and categorization of sake below to identify which sake produced in which method.

Class by rice polishing ratio and brewed alcohol

With brewed alcohol

  • Futsushu(regular) 普通酒
    Approximately 70% of sake is in this class. If the sake is not class in other class, it is futsushu.
  • Honjozo 本醸造
    Sake with polishing ratio under 70%(30% and above polished) and brewed alcohol added.
  • Tokubetsu Honjozo 特別本醸造
    Sake with polishing ratio under 60% and brewed alcohol added, and using special brewing method.
  • Ginjo 吟醸
    Sake with polishing ratio under 60% and brewed alcohol added.
  • Daiginjo 大吟醸
    Sake with polishing ratio under 50% and brewed alcohol added.

 

Without brewed alcohol

  • Junmai 純米
    If no brewed alcohol added but not so much of rice polished, it is Junmai
  • Tokubetsu Junmai 特別純米
    Sake with polishing ration under 60% and no brewed alcohol added, and using special brewing method
  • Junmai Ginjo 純米吟醸
    Sake with polishing ration under 60% and no brewed alcohol added
  • Junmai Daiginjo 純米大吟醸
    Sake with polishing ration under 50% and no brewed alcohol added

 

Category by storing period and season
  • Shinshu 新酒
    Shinshu means new sake, and traditionally shinshu means sake of the current year vintage.
    Thesedays, shinshu and shiboritate has similar meanings and it means fresh sake right after brewing
  • Koshu 古酒
    As a contrast to shinshu, koshu means old sake and traditionally meaning old vintage.
    These days, the meaning is more to aged sake.
  • Natsuzake 夏酒
    Natsuzake means summer sake, and it is new word in recent market.
    it tends to be fresh and high acidity to make people drink easily in hot and humid summer in Japan.
  • Hiyaoroshi ひやおろし
    Hiyaoroshi or Akiagari is sake of autumn.
    It design to age over summer to release in autumn season, and have thick and rich taste.

 

Category by heat pasteurization process
  • Namazake 生酒(Hon Nama 本生)
    Sake is normally heated twice before delivery: after fermentation and before delivery.
    Namazake means no heating process before delivery, so easy to go off but have more genuine taste.
  • Nama Chozoshu 生貯蔵酒
    Heat sake only once before delivery.
  • Nama Tsumezake 生詰め酒
    Heat sake only once after fermentation.

 

Category by Joso process
  • Arabashiri 荒ばしり
    When squeeze moromi, first squeeze is Arabashiri.
    tends to be rough but powerful taste. Slightly coloured white.
  • Nakagumi 中汲み/Nakatori 中取り
    After arabashiri it is Nakgumi or Nakatori.
    It has more balanced flavor and taste compared with other.
  • Seme 責め
    Last squeeze is Seme.
    Alcohol is slightly higher and have richer taste.
  • Fukuriduri 袋吊/Shizukutori 雫取り/Tobinkakoi 斗瓶囲い
    If not squeeze by machine , but hung to collect drops it is Shizuku
    No noise in the taste, smooth and clear.

 

Other
  • Genshu 原酒
    If no blend and no water added after fermentation it is Genshu.
    Genshu tend to have strong characteristic and straight taste.

 

Rice

Rice used in sake brewing is different to what we eat.
The main differences between 2 kinds of rice are as below;

  •  Larger grain
    As grain is larger, when polished it is difficult to break up
  •  Bigger Shinpaku
    Inner core which is Shinpaku has starch and has a important role in koji and sake making.
    Outer core has protein or vitamin which will be a noise in sake brewing, but umami when eat.
  •  Easy to brew
    Characteristics such as absorb water more make it easy to make sake and koji

 

As you can see above, sake rice and eating rice is different and also it was designed to be different.
Upon ling history, not only breweries and their technique developed.
Farmers developed rice variety for sake brewing in their region.
Now, you can find some example of sake rice below to understand how each variety different.

 

Example of sake rice
  • Yamada Nishiki 山田錦
    The most suitable for sake brewing and so-called King of rice.
    80% is produced in Hyogo prefecture and A+(Highest rank) is onlhy produced in Hyogo. Tends to be rich taste.
  • Gohyakumangoku 五百万石
    Produced in Hokuriku region such as Niigata, and has the largest planting area
    2nd famous rice after Yamada Nishiki, and tends to be refreshing taste and crispy finish
  • Omachi 雄町
    Found in 100years ago and only sake rice used in today’s brewing. It is a root of Yamada Nishiki and Gohyakumangoku.
    95% of total production is in Okayama prefecture. Tends to be roundy-shaped and rich taste.
  • Hattan Nishiki 八反錦
    It is a cross between Sake rice Hattan and eating rice Akituho, and grown in Hiroshima.
    Tends to be refreshing crispy finish.
  • Goriki 強力
    Recently revived sake rice in Tottori prefecture, and originate from Omachi
    It is required to have some knowledge and technique to brew, but sake with this rice is good for aging and have identical acidity.
  • Ginpu 吟風
    Improved variety for sake brewing in Hokkaido
    Tends to be full-bodied rich taste
  • Kame no O 亀の尾
    Grown in Shonai in Yamagata prefecture, originating from eating rice
    You can feel gentle acidity and clearness from clean water in Yamagata
  • Dewa Sansan 出羽燦々
    The sake rice only grown in Yamagata prefecture
    dry and refreshing taste.

 

Water

 

 

Water is also one of the most important element in sake brewing.
From washing and soaking rice, more than half of sake is water.
When we talk about taste, hardness is one of the indicator which decides sake taste
Hard water means more mineral inside, and harder the water it tends to be dry.
On average water in Japan is soft, there is harder water near mountains as well
You can find some example of hardness of the water by region.

 

Koji・Yeast

 

 In sake brewing, brewers say [1 Koji, 2 Moto, 3 Brew] so we can say koji making process is the most important.
 Koji convert starch in rice into glucose and without glucose there will not be a fermentation.
 When we make koji, add koji seed, so called Moyashi, to steamed rice to make koji, and below is some kinds of koji seed.

 

Type of seed koji
  • Black koji 黒麹
    Originally from Okinawa island and spread to Kyushu island.
    Generally, it will be thick, rich but crispy finish sake. It can be used to design sake with high acidity.
  • White Koji 白麹
    Originated from black koji and mainly used in Kyushu.
    it will be mild and gentle taste.
  • Yellow Koji 黄麹
    Mainly used in sake brewing, but used in shochu making thesedays.
  • Red Koji 紅麹
    Used in sake, miso making in Japan and shaoxing making in China.

 

After koji convert starch into glucose, yeast start converting glucose into alcohol and gas.
So, yeast decides taste and quality of alcohol itself but the gas it produce is aroma and flavor of sake.
With different yeast, sake will show us different face even same ingredients are used.
Yeast is found in breweries and living in its wooden building, but nowadays Japan Brewing Association develop and produce for all the breweries.
Please find some example of yeast below.

 

Example of Yeast
  • Kyokai No.6
    Produced by Japan Brewing Association and found in Aramasa brewery in Akita.
    The oldest yeast used in today’s brewing.
    The taste will be gentle and dry taste with this yeast.
  • Kyokai No.7
    Produced by Japan Brewing Association and found in Miyasaka brewery in Nagano.
    The taste will be mellow flavor and balanced taste with this yeast.
  • Kyokai No.9
    Produced by Japan Brewing Association and found inKumamoto brewing laboratory.
    It is so-called the base of modern ginjo brewing,.
    Not much characteristics, but it reflects characteristics of breweries in their taste of sake.
  • Kyokai No.1801
    Developed in Japan Brewing Association.
    It produce the most aroma through fermentation.
    Ideal to use for Daiginjo brewing
  • Alps yeast
    Developed in Nagano prefecture. These days, each prefecture develop original yeast to stand out their originality.
    Less acidity, but fruity flavor like apple with this yeast
  • Flower yeast
    Developed in Tokyo Agricultural University from flowers.
    With different flower, it will be unique different flavor and taste
    No flower aroma with flower yeast.