Tamagawa Glossary of Sake Terminology

A, B, C, D, E

Brewer's alcohol. Distilled alcohol, used in making some kinds of sake (regular futsushu, honjozo brews and non-junmai (alcohol-added) ginjo and daiginjo). We age most of ours in-house for a full year before use.
BY. Short for “Brewing Year”, showing the year in which a sake was brewed.   Using an English abbreviation ensures that most ordinary Japanese people don’t know what’s going on. The fact that the year itself is given in the Japanese reckoning (the year of the current Emperor’s reign) should be enough to complete the set by confusing most foreign customers. 
The current Emperor has been on the throne since 1989, so the year 2000 was Heisei 11, 2010 was Heisei 21, and so on. If you are lucky enough to come across something from 63BY or earlier, that is sake from the previous Emperor’s reign, which was known as Showa.
The Brewing Year used to start on October 1st (still designated Sake Day), reflecting the traditional brewing season (from late autumn till spring). Now it runs from July 1st until the end of June the following calendar year, so some sake made in 23BY (the season beginning in 2011) will be brewed in the spring (or possibly early summer) of 2012.
Daiginjo. A Special Designation. The rice used must be polished to 50% or less of original size.

F, G, H, I, J

Flavours and tastes. Western thought traditionally held that the human tongue recognized four basic tastes, namely sweet, sour, salty and bitter. Recently it has become accepted that there is a fifth - umami - used as a loanword because of the lack of an acceptable English equivalent. Japanese discussion of flavours also frequently involve shibumi - astringency. This is the mouth-puckering sensation associated with red wine or strong tea, and can be said to be more of a sensation than a taste. The idea of gomi ("five tastes") was imported from China, and is often used as a kind of shorthand for the totality of sake flavour. The original five were sour, bitter, sweet, dry and salty.
Futsushu - (literally, "Ordinary Sake"). A term which describes sake not made to the specifications of the Special Designations (SD), whether because the rice is not polished enough, the addition of brewer's alcohol is larger than that permitted for SD, or because other additives (like sugars or organic acids) have been used. Tamagawa sake made in this class uses only brewer's alcohol.
Genshu. Undiluted sake.
Ginjo. A Special Designation. The rice used must be polished to 60% or less of original size.
Go. 180ml in the traditional Japanese reckoning. Common bottle sizes include four go (720ml) and one go.
Gohyakumangoku. Now the most widely grown of all sake rice strains, this was originally developed in Niigata Prefecture.
Hiya-oroshi. Sake which was cold-bottled (without the conventional second pasteurisation), and traditionally appeared in autumn, at about the time the temperature of the sake in storage matched that outside. September the 9th is called Hiya-oroshi Day.
Honjozo. A Special Designation ("true brew" sake). Made with rice polished to 70% or less of original size, with a limited addition of brewer's alcohol made to the mash before pressing.
Iwai. A brewer's rice variety unique to Kyoto Prefecture.
Junmai (junmaishu). A Special Designation (literally, "pure rice sake"). Originally, it was stipulated that the rice be polished to 70% or less, but that requirement no longer exists. Sake is made in this style without using brewer's alcohol or other permitted adjuncts.
Junmai Daiginjo. Daiginjo sake (q.v) to which no brewer's alcohol has been added.
Junmai Ginjo. Ginjo sake (q.v) to which no brewer's alcohol has been added.

L, L, M, N, O

Kaiseki. A formal style of Japanese dining, with great emphasis on the passing of the seasons and multiple courses.
Kimoto. An antique system of making the yeast starter, and by extension, sake made with it. It uses a natural lactic acid fermentation to acidify the mash, unlike modern sokujo in which lactic acid is added at the beginning. Kimoto school yeast starter (which includes the later variant, yamahai) takes about a month to prepare.
Kitanishiki. Extremely large-grained brewer's rice variety from Hyogo Prefecture.
Koji. A variety of mould (Aspergillus oryzae) grown on steamed rice in the brewing process. Enzymes from the mould break down the starch in the rice to produce fermentable sugars. The handling of this process is the key to successful brewing, and this microorganism is responsible for much of the unique character of sake. The word is used by extension to signify steamed rice on which the mould has been propagated.
Kura. In general Japanese usage, a warehouse. In the sake world, a brewery.
Kurabito. Literally "brewery people", this refers to the brewing staff (other than the Master Brewer).
Kuramoto. The owner (usually hereditary) of a sake brewery.
Moto. Japanese for the yeast starter (also called shubo).
Muroka nama genshu. Undiluted, unfiltered, unpasteurised ("3U") sake.
Nama, namazake. Unpasteurised sake with a distinctive fresh flavour and smell.
Namachozo. Sake which is stored unpasteurised, then heat-treated only once at the bottling stage.
Namazume. Sake which is pasteurized once, but not heat-treated at the bottling stage.
Nigori (nigorizake). Literally "cloudy sake", this style is pressed using a wider mesh to allow rice and koji sediment to remain in the sake.
Nihonbare. Although not strictly a brewer's rice variety, it is widely grown for use in sake making.
Nihonshu. Another word for sake, signifying literally "Japanese sake".
Omachi. Venerable brewer's rice variety from Okayama Prefecture.

P, Q, R, S, T

Pasteurisation. A heat-treating process to sterilize foodstuffs, called hi-ire in the sake world. Used in sake breweries to stop yeast and enzyme action, and especially to kill off spoiling lactic acid bacteria. Named for its discoverer in the West, Louis Pasteur, though it had been in use in Japan's sake breweries for centuries before he was born.
Rice polishing. The first process in sake making, it involves grinding away the outer portion of the rice kernel with special machines. Done in-house at our brewery.
Rice polishing ratio. The proportion of the grain remaining after polishing, given as a percentage. A defining characteristic of some of the Special Designations.
Sake Meter Value (SMV). A measure of specific gravity, used as a measure of sweetness (or dryness). Numbers with a plus indicate drier sake, those with a minus figure tend to be sweet. Other flavour elements (especially acids and amino acids) affect how a sake tastes, so the SMV is at best only a rough guide. Below are a few Tamagawa products and their SMVs to give you an idea.

Man-Eating Rock +7 (Definitely dry)
Daiginjo +4 (Dryish)
Tamagawa +2 (Neutral, perhaps a little sweet)
Junmai Ginjo Iwai -4 (Sweet)
Time Machine -80 (Beyond sweet)
Shiboritate. Literally "just pressed", refers to new sake immediately after it has been pressed.
Shizuku. Sake that is not pressed in the conventional way. The fermenting mash is poured into long cylindrical bags, which are then strung up. Only the sake which drips out naturally is collected, making for fine sake but low yields.
Sho. 1.8L in the traditional Japanese reckoning. The size of the large standard sake bottles.
Shubo. Alternative term for moto, the yeast starter.
Sokujo. The standard modern method of making the yeast starter. Pure yeast cultures and lactic acid are added at the outset to control unwanted (wild) yeasts and other microorganisms. It takes about two weeks to produce yeast starter by this method.
Special Designations. A group of terms specifying the raw materials and brewing methods used in making certain kinds of premium sake.
Spontaneous Fermentation. This expression is used by us to describe kimoto and yamahai sake made in the pre-modern way without adding pure yeast cultures.
"Three U". We use this term to describe sake which is undiluted, unpasteurised and unfiltered.
To. The equivalent of 18L in the traditional Japanese reckoning. Glass bottles of this size are usually used to hold competition shizuku sake.
Toji. A Master Brewer, responsible for all the brewing at a given brewery.
Tokubetsu Honjozo. A Special Designation. Made with the same limited addition of brewer's alcohol as for honjozo, but made with more highly polished rice or by special brewing methods.
Tokubetsu Junmai. A Special Designation. Made to the same specifications as for junmai, but made with more highly polished rice or by special brewing methods.

U, V, W, X, Y, Z

Umami. The sixth basic taste, originally identified as the flavour treasured in Japanese dashi stock made with seaweed. It is the taste that deepens as tomatoes ripen or parmesan cheese ages, and is now a familiar concept to food and drink specialists the world over, and a key element of sake flavour.
Yamada nishiki. A brewer's rice variety, widely held to be the finest of all. Originally developed in Hyogo Prefecture.
Yamahai. A laborious system of making the yeast starter, yamahai is a variation on kimoto, in which the grinding of the mash (yama-oroshi) is omitted.
Yama-oroshi. "Grinding the moto". Grinding the mash into a paste when making kimoto yeast starter. Also known as moto-suri.
Yeast starter. A "seed mash" made at the beginning of the brewing process to propagate pure sake yeast.