Brewing: Japanese Sake is made by fermentation process by yeast like wine, but, it has more complex brewing process. Before fermentation, sake rice needs to be changed into sugar using Koij (a type of mold) which is made from rice. Fermentation occurs when sake yeast is added. Besides koji and yeast, the quality of water is also very important and many breweries take advantage of the various kids of natural water available in Japan.
Seimai Buai: Milling ratio. Usually indicated as a percentage on the label, this refers to the amount of rice that remains after milling. If "Seimai Buai 40%" is indicated on the label, 40% of the rice is remained. Basically, the lower the percentage, the higher the grade of the sake.
Sake Serving Temperatures
55C and above: tobikiri-kan (literally ‘flying out’), ie scalding
50C: atsu-kan (piping hot)
45C: jyoh-kan (high heat)
40C: nurukan (luke warm)
35C: hitohada-kan (body temperature)
30C: hinata-kan (sunbathed)
20C: hiya/jo-on (room temperature)
15C: suzu-hie (cool, lightly chilled, or ‘autumn breeze’)
10C: hana-hie (‘flower-cold’)
5C: yuki-hie (‘snow-cold’)
0C to -5C: mizore-zake (frozen sake ie, a sake slushie)
It is really up to personal preference, but here are some guidelines about sake types and temperatures.
- Warming sake increases its aroma, so it can make a sharp, dry sake taste more complex and aromatic. But overheating may cause it to taste too sharply alcoholic and acidic.
- Very dry sake can withstand high temperatures. As it already tastes dry and boozy, it’s less at risk of the heat unhinging its inherent characteristics.
- Floral, fruity sake like daiginjo and ginjo sake are better served at cooler temperatures to appreciate their delicate taste and mouthfeel. That said, some more robust ginjo really flourish when warmed a little.
- Honjozo and junmai varieties work well heated, which will bring out their complex characteristics, rich rice and koji elements, and notes of cereals and honey, and give them more body as well as a smoother texture.
- Koshu (aged sake) is suitable for heating, which will enhance its already rich flavour profile.
- Nama (unpasteurised) varieties are best served chilled to appreciate their fruitiness and fresh flavours. Sakes that are served too chilled will dull its flavour profile.
Grade of Japanese Sake:
Junmai Daiginjo (純米大吟醸) Brewed using only rice, water, yeast and koji. There are no other additives. To qualify as a Daiginjo, the rice grain must be milled to 50% or less of it’s original size. This alcohol is high on fragrance and has a full body, delicate taste and a brief tail.
Daiginjo (大吟醸) sake is the same as Junmai Daiginjo except a small amount of distilled brewer’s alcohol is added to the sake to achieve different flavor profiles.
Junmai Ginjo (純米吟醸) Sake is brewed using only rice, water, yeast and koji. There are no other additives. To qualify as a Ginjo, the rice grain must be milled to 60% or less of it’s original size.
Ginjo (吟醸) Sake is the same as Junmai Ginjo except a small amount of distilled brewer’s alcohol is added to the sake to achieve different flavor profiles.
Brewer’s of Ginjo-shu use a special type of yeast and the rice mash is fermented in low temperatures. It also requires labor-intensive techniques to prepare the sake. It is best served cold to retain its flavor and aroma.
Junmai (純米) sake is brewed using only rice, water, yeast and koji. There are no other additives. To qualify as a Junmai, there is technically no minimum milling requirement, but the sake must be the “pure rice” style… no added distilled alcohol allowed.
Honjozo (本醸造) sake must be milled to 70% or less of it’s original size and as far as ingredients go, it contains a small amount of distilled brewer’s alcohol, which is added to the sake to achieve different flavour & aroma profiles. It also makes the aroma of the drink distinct and easily identified. The Honjozo-shu is ideally served warm.
Tokubetsujunmai (特別純米):Ingredients: Rice and Koji, Seimai Buai: less than 60% remaining, special brewing method
Tokubetsuhonjozo (特別本醸造): Ingredients: Rice, Koji and Distilled alcohol, Seimai Buai: less than 60% remaining, special brewing method
Yamahai (山廃 in Japanese) brewing method: An older way of making the yeast starter. The difference between the regular yeast starter method and Yamahai is the way that the lactic acid needed to begin yeast fermentation is obtained. In Yamahai starters, bacteria that produces lactic acid are grown in the tank first, and then yeast fermentation begins when the necessary acid level is reached. The word "Yamahai" is an abbreviation of a longer term, "Yamaoroshihaishimoto", which means to skip the step of mashing down steamed rice wtih wooden poles that was common to Sake making before the Yamahai method developed, and continues to be part of the Kimoto method even today.
Namazake (生酒) basically means that the alcohol is not pasteurized. Most sakes are pasteurized twice. The purpose of pasteurization is to stabilize the Sake by eliminating bacteria and by deactivaing enzymes. All types of sake can be Namazake. Therefore, Junmai-shu, Ginjo-shu or any other types of sake can be Namazake. This style is becoming popular in Japan, and Namazake needs to be refrigerated so that the flavor and aroma of the drink does not change.
Nigori-zake (濁り酒) is unfiltered sake; it is cloudy and often has some koji rice in the bottle. It is sweet and makes a great dessert drink.
Koshu (古酒) is sake aged for longer than 1 year. Ideally sake should not be matured for more than 9-12 months. Koshu has a rougher, stronger texture and intense flavour.