02 Rice Polishing | Washing | Steaming

There are broadly two varieties of rice: indica, a long grained variety, and japnica, a short-grained variety. Each of these can further be subdivided into sticky and non-sticky rice. Non-sticky japanica rice grown in Japan is used to brew sake in Japan. This is the same type of rice that Japanese people normally consume as food. Many types of premium sake are made with sake rice, which is especially suited to sake breaking. Features of sake rice are large grains, low protein content, and high solubility during the brewing process. 
Water is vital for making quality sake. Japan receives abundant rainfall. Forests occupy 60% of the land surface and water is plentiful. Historically, sake makers erected breweries in locations with access to good-quality water. 
Rice Polishing
The other layers of unpolished rice contain large amounts of fats, minerals and proteins that spoil the flavor of sake, therefore the rice is polished using a high speed rotating roller. Normally, the outer 30% of the grain is removed, leaving the central 70%. This polished rice is known as 70% polished rice or is said to have a seimai-buai (polishing ratio) of 70%. For ginjo-shu, the outer 40% or more of the grain may be removed. 
Washing and Steaming
After milling, the polished rice is washed in water to remove the bran and is left to steep in water. When the grain has absorbed 30% of its weight in water, it is removed from the water and steamed for about one hour. Steamed rice is less moist and sticky than boiled rice, making it ideal for use in sake production.