For thousands of years, Japanese brewers have cultivated, understood and worked with rice to make one of the world's finest nectars: sake. To learn about rice is to understand sake.
Despite its long history in Japan, rice was for a long time purely a food for warriors and aristocrats. It only became a staple diet for the majority of the population after the 17th century. It was not until the early 20th century that it came to dominate Japanese dishes.
The origin of rice cultivation in Japan is relatively blurry, with several theories around how the grain was first introduced to Japan. It could have been from the Korean Peninsula, the lower region along the Yangtze River, or China's South-West Islands during the third century B.C. However, what is certain is that rice quickly became central to Japan's culture and economy.
Approximately 300 kinds of rice are cultivated in Japan alone today, but only a small amount is suitable for making the tasty and aromatic sake we love.
In Japan, most of the rice grown is Japonica rice. As a whole, Japonica rice comprises a little more than 20% of the global production of the grain. Over 90% of the rice consumed in Japan is Uruchimai, whereas Mochigome is a sticky and sweeter type of rice used to make soft and delicious mochi rice cakes.
About Sake Rice
Not all rice is born equal. While there are hundreds of varieties, only a minority of them are suited for sake brewing. The rice used to brew sake is called "sakamai", literally "sake rice." A distinct extra type best suited to sake brewing is aptly named "shuzo-kotekimai", directly "rice perfectly suited to brewing" in Japanese. Sakamai and shuzo-kotekimai account for only 5% of the total rice production in Japan.
What makes good sake rice?
To make great sake, brewers need to use rice that has the following characteristics:
- Large grain size.
- Has “shinpaku” or white core (starch concentrated in the middle of the grain).
- Lower levels of lipids and protein (to minimise off flavours).
- High water absorption rate.
- Be hard on the outside and soft on the inside after steaming.
Because sake rice grains or "shuzo-kotekimai" are larger, rice plants are larger and taller. As a result, sake rice plants are more difficult to cultivate and harvest than other varieties. The heavier grains also cause the plant to be top-heavy and more vulnerable to strong winds. It is why sake rice is a lot more expensive than regular food rice or even grapes used to make wine.
In the category of "shuzo-kotekimai" rice varieties, Yamada Nishiki is probably the most famous one. Its outstanding polishing ability makes it an ideal choice for producing sake that is both elegant and delicate, such as daiginjo types. Yamada Nishiki soon became the sake rice variety with the most extensive cultivation area in Japan after the ginjo boom of the 1980s.
Other significant "shuzo-kotekimai" used in sake brewing are Gohyakumangoku, Miyama Nishiki, Omachi and Hattan Nishiki.
Rather than the rice itself, the difference in sake flavour and aroma is primarily determined by the skills, techniques, and vision of the toji (master brewer) and his/her kurabito (brewery workers). However, breweries have been conducting increasing amounts of research on the impact that shuzo-kotekimai has on sake's flavour profile and composition. This trend goes hand in hand with the growing notion of terroir in the sake industry, as tojis are trying to add locality to their brew.