What is Sake?
The word sake, also referred to as “shu”, literally means “alcohol” in Japan. In Japan the word sake can mean any alcoholic beverage. That is why when Japanese speak English they will refer to “sake” as “Japanese sake”. People in japan commonly refer to sake as Nihon shu. When in Japan, using the term “nihon shu” for sake will impress local Japanese shop owners.
The origins of sake can date as far back as 2000 years ago. However, sake in it’s more refined form as we know it today is more like 1000 years. The premium “ginjo” sake on the market today have only been around for the last forty years.
Unlike spirits such as vodka, sake is not distilled. Sake is sometimes described as rice wine. Unlike wine, which is simply fermented grape juice, sake is brewed from rice. Sake has four main ingredients: Rice, Water, Koji and Yeast. While sake and beer share the process as brewed beverages there are some distinct differences. With beer, there is an orderly sequence to achieve fermentation. Beer will these steps independently in chronological order
- convert starch to sugar,
- then sugar to alcohol fermentation will follow.
For sake, starch to sugar conversion and sugar to alcohol conversion occur simultaneously. Thus producing the highest alcohol content of any non-distilled beverage. There are other differences with beer brewing as well. Obviously sake is produced with rice. Beer has other fermentable ingredients. Sake also uses koji mold to convert starch to sugar. Beer will use malting to create enzymes for converting starch to sugar.
Here is a simple breakdown of how sake is made: After the rice is milled, the rice is washed and soaked. Washing will removed any residue after milling, and soaking to absorb water. Next the rice is steamed. After steaming rice is divided among two locations, either in the tank or the koji room. About 25% of the rice goes to the koji room which is sprinkled with koji and kept warm. Next, a yeast starter is created in a small tank. This is the concentrated beginning of sake ingredients (rice, water koji and yeast). The fermentation in the open tank will last as long as 20-40 days. This mash is then pressed and squeezing and separating the liquid from the rice mash. The liquid that remains is basically sake at this point.
What makes a good sake? While water is the main ingredient of sake, rice is the most costly ingredient. Sake rice (sakamai) is different than rice used for eating. Sake rice is larger and more expensive to grow. There are about 100 different varieties of sake rice. Good and premium sake rice is expensive, but worthy of making a premium final product.
Milling is the process of polishing the rice. The center of the rice (shinpaku) is the opaque center that contains the highly coveted starch. The outer portion of the rice grain contains fat and protein which will inhibit fermentation. Some premium sake polish their rice up to 50%.. Therefore, when purchasing the expensive sake rice, only half of the raw product is used for such premium grades.