Saké Grades and Rice Polishing Ratio

Rice is the main fermentable ingredient used to brew saké, and it’s often considered the single most important ingredient.

One of the major differences between the various grades or classifications of saké is related to the rice-polishing ratio, or seimaibuai (pronounced “say-my-boo-eye”).

Rice is milled or “polished” before being used in brewing to eliminate the fats, proteins, and minerals on the outer portions of the grain that can inhibit fermentation and cause off flavors in the finished product. In general, the more the rice has been polished, the more refined and elegant the saké’s flavor profile will be.

The seimaibuai is expressed as a percentage representing the amount of the original rice grain that remains after polishing. As a point of reference, the white table rice with which we are all familiar has usually had 10% of the outer portion polished away, so its seimaibuai is 90%.

Around 74% of all saké produced in Japan is futsushu, “ordinary” or “table” saké, and this is the type of saké (served hot, Hot, HOT!) that most people in the U.S. encounter for the first time at their local Japanese restaurant. The rice used in making this saké has a seimaibuai of less than 70%, meaning less than 30% of the original grain has been polished away.

At Saké Nomi, we specialize in premium saké, which makes up the remaining 26% of saké produced in Japan. In Japanese, this grouping of saké classifications is referred to as tokutei meishoushu, or “special designation saké.”

To be designated as a premium saké, the rice used to brew the saké must have a seimaibuai of 70% or greater, meaning at least 30% of the original grain has been polished away. The six main classifications of premium saké are as follows:

Though many things can affect whether a saké tastes sweet or dry (including acidity, serving temperature, mineral content of the brewing water, and previous dishes or accompanying food), one numerical guide that may be helpful, and can often be found on a bottle label, is the saké’s nihonshu-do or Saké Meter Value (SMV).

A saké’s SMV is its specific gravity; the density of the saké compared to the density of water. Theoretically, the higher (positive) the number, the drier the saké should taste. Conversely, the lower (more negative) the number, the sweeter the saké might taste. An easy way to remember this relationship is the phrase, “Higher is drier.”

While the SMV scale is generally seen in the -5 to +15 range, it’s important to remember that a saké’s SMV number is most useful and accurate in its extreme manifestations, and, as mentioned above, there are countless other factors affecting how one interprets sweetness and dryness.

Though traditional standards held that “real” saké was on the dry side, sweeter tasting saké has recently become more popular. Today’s average SMV hovers somewhere around +4.

In the end, the SMV is just one way for the consumer to get a general idea of how a saké might taste. No two palates are the same, however, and when it comes to evaluating and appreciating saké, there’s no substitute for experience. Kanpai to that!