Written by Mark Whiteman, Sake Expert, Tokyo Liquor NZ.
World Sake Day, officially recognised on October 1 in 1978 by the Japan Sake and Shochu Makers Association, is a perfect day to honor the Japanese sake tradition.
The day commemorates the start of sake-making season in Japan, as October is considered to be the best period to begin making sake.
In Japan, the start of seasonal cooler temperatures is necessary for proper fermentation, and the winter months allow for precise control of yeast and enzymatic activity to produce high-quality sake with the desired flavors and aroma.
SAKE IS MORE BEER THAN WINE OR SPIRIT
Sake is not a distilled spirit, and neither is it a “rice wine” as it is commonly mistaken for. Made through fermentation, sake actually has more similarities to beer than wine.
The rice used for sake comes in many varieties, each giving different flavors and aromas to the sake. These are not the type of rice that the Japanese consume during meals.
Brewers ensure the rice is polished to the right degree by milling the grains and removing the bran to get top-quality sake.
Rice absorbs fatty acids, proteins, and minerals from the environment. These are good for nutrition, but not for making sake, so the rice needs to be milled to get rid of the “zatsumi” (unwanted flavours). The remaining bead of starch is then used to make sake.
Depending on how much of the rice is polished, the sake is then categorised into different grades. The general rule is, the more you polish the rice, the higher the sake grade will be.
When you see a percentage number on sake bottles, it usually doesn’t refer to alcohol content but the polishing ratio.
For the highest grade, daiginjo, the rice polishing ratio is 50% or less, meaning at least half of the original rice is milled away, leaving only 50% for fermentation.
The “rice polish ratio” written on the bottles is “the percentage of the rice left over after the polishing” and not “the percentage polished away” (it’s a bit counter-intuitive). So, the lower the percentage, the higher the grade.
The fermentation process takes place after the rice is polished, which is way more complex than winemaking.
Rice does not have residual sugar like grapes that are used in wine, so for fermentation to start, the sake master brewer, known as toji, has to first steam the rice and sprinkle koji.
Koji is a mold that produces enzymes to convert rice starch into fermentable sugars. It is also used in making miso, shochu, and vinegar.
The rice is turned into sugar when koji is added, and the yeast will then start converting the sugars into alcohol.
After fermentation is complete, the sake is usually pasteurized and put into tanks for between three to six months for it to mature. The resting period allows the sake to mature into a more mellow and softer brew.
Very important for sake making is a good source of pure water that is used from washing the rice to diluting the end product.
The water and level of minerals in them will determine whether the sake ends up being on the softer scale or dry.
Sake comes in different grades, from the “ordinary sake” or Futsu-shu, to special premium sake, the Tokutei meisho-shu.
Those that are made purely from rice are often labeled as junmai or “pure rice” sake. If you do not see junmai on the label, it usually means they have distilled alcohol or “brewer's spirit” added.
Ginjo sake is made with rice polishing of below 60% meaning at least 40% of the rice grains have been milled away, and Daijingo is considered the highest grade with rice polishing below 50%.
A sake with a light and smooth texture and flavour is the Honjozo-grade sake, where the rice is about 30% polished and contains about 3% of brewer’s spirit.
Sparkling sake is made similarly to normal sake, but the fermentation is stopped at an earlier stage when there is still a lot of sugar, and is then pressed and bottled. This allows the sake to go through a second round of fermentation while it is in the bottle, which produces carbonation.
Some producers of cheaper sparkling sake choose to add carbon dioxide, like soda.
SAKE HOT OR CHILLED?
As a general rule of thumb, you shouldn’t heat up the higher grades of sake. They can be very delicate and will taste good chilled, but when heated, they may not fare well.
Conversely, medium to lower grades of Sake are often selected for heating.
Your choice of either having it hot or cold will offer you a totally different sake experience.
