Sake, also known as “rice wine” in English and “nihonshu” in Japanese, is an alcoholic beverage made from fermented rice. This alcoholic beverage has many different varieties that are determined by the extent of rice milling, the alcohol added after fermentation, and the post-processing that pasteurizes, strains and filters.
Basic Varieties of Sake
Sake that is produced from the fermentation of rice includes two main elements: the extent of milling and polishing of the rice, and the amount of distilled alcohol added after the sake is brewed. The main types of sake have the following characteristics:
Usually, in junmai-shu more than 30% of the rice husks are removed, creating rich, full-bodied sake that is high in acidity. It has an intense flavor, but is less fragrant than other sakes. It is often served hot.
Usually, more than 30% of rice hull is milled away, and some distilled alcohol is added to create honjozo-shu. It is fragrant and sweet, with a pervasive flavor. It’s often served warm, and is considered a light sake due to the added grain alcohol. The added alcohol helps enhance the aroma.
More than 40% of the outer layer of the rice grain is milled away to create ginjo-shu. If alcohol is added, it’s called “ginjo.” Without adding alcohol, it is called “junmai ginjo.” More complex than most other sakes, ginjo-shu has a more subtle and delicate flavor due to the more extensive milling process. Brewing ginjo requires more labor than most sake brewing. The result is a fragrant, soft and delicate sake with intricate flavors. It is usually served cold so that the flavors are not lost.
For making daiginjo-shu, more than 50% of the rice layer is milled away. If alcohol is added, it’s called “daiginjo.” If no alcohol is added, it is called “junmai daiginjo.” This sake is considered high-end sake, due to the deeper milling of the rice. It is very fragrant, with a fleeting aftertaste and a full body. However, the flavor profiles of daiginjo vary due to the variety of processes used to create this sake. Daiginjo-shu is often considered a high-end type of ginjo-shu, and is served cold.
As you see, different varietals of sake require different extents of rice milling. The type of sake also depends on whether or not extra alcohol is added after the fermentation process. In any one group of sake types, there will be variation. For example, sometimes the skill of the brewer and the quality of the rice or water used has a bigger impact on flavor than the milling process.
Processed Sake Types
The basic varieties of sake can be post-processed in many different ways. The final processing of the sake is just as important as the quality of rice used and the amount of alcohol added in ultimately determining the characteristics of the sake.
After the initial brewing process, most types of sake are diluted with water to bring the alcohol content down to about 15%. Genshu is the exception and is a general term referring to undiluted sake. This means it usually has a higher alcohol content than other types of sake.
In seishu sake, the sediment from the rice is strained out, creating a clear liquid. This can be done in two ways – through pressing or through dripping. When the sake is drip-strained, it is known as “fukurozuri.” This is the only type of rice wine that can legally be called “sake” in Japan.
Unlike seishu, nigorizake retains the rice hulls and thus has a cloudy appearance. It is never filtered. This gives it a sweet, mild flavor and a fruity bouquet. It must be shaken before being served, and is usually served chilled.
If sake is strained, removing the sediment, but is not filtered through carbon filtering, it is known as muroka sake. This sake has a stronger flavor than carbon-filtered sake.
Namazake is sake that never undergoes a pasteurization process. This means it needs to be stored refrigerated and goes bad much more quickly than most sake.
Most sake undergoes a short aging process. Koshu sake, on the other hand, can be aged for years. This gives it a sweeter flavor and a golden color. If it is aged in wooden barrels or casks, which impart a powerful flavor onto the sake, it is known as “tarazuke.”
Shiboritate is sake that has not undergone the typical half-year aging process that most sake requires during processing. This produces a younger, more acidic wine.
Determining what kind of sake you are purchasing will help you to better understand how to serve and properly store it. Filtered and unpasteurized sakes generally have a shorter shelf-life and should be stored refrigerated. High-quality or expensive sake is almost always served cold, so these should be refrigerated as the time of drinking nears. Low- to medium-quality sake is often served hot, especially during the winter. Always serve sake in insulated bottles, or sake bottles to ensure that the beverage is presented at its optimal temperature.