Sake, soju and shochu

The Western bar converts starch with malt. East Asia converts it with a mold. Koji, the culture of Aspergillus oryzae grown on steamed rice, is the quiet engine behind sake, shochu and the oldest Korean soju, and understanding it is the whole key to three drinks that are routinely mislabeled as rice wine, Japanese vodka and Korean vodka.

Sake: brewed, not distilled

Sake is made from rice, water, koji and yeast. The rice is milled to remove the outer layers of protein and fat; the milling ratio, the share of the grain that remains, is the first number on a serious label. The polished rice is washed, soaked and steamed, and a portion is inoculated with koji spores and tended for about a day until the mold's enzymes are ready. In the fermentation tank, koji breaks starch into sugar while yeast turns that sugar into alcohol at the same time, in the same vessel. The Japan Sake and Shochu Makers Association calls this multiple parallel fermentation and notes that no other drink is made this way. The result is pressed, usually pasteurized, and bottled at around 15 percent, a little above wine.

The grades follow milling and additions. Junmai means rice, koji and water only. Honjozo permits a small addition of brewer's alcohol and requires milling to 70 percent or less. Ginjo requires 60 percent and a slower, colder ferment that gives fruit and flowers; daiginjo requires 50 percent. Junmai ginjo and junmai daiginjo combine the two conditions. Tokubetsu marks a special process or rice. Other words describe treatment: nama is unpasteurized and must stay below 5 C; genshu is undiluted and stronger; nigori is coarsely pressed and cloudy.

Brewing is winter work, and water matters: soft water gives lighter sake, hard water fuller. Japan's liquor GI system, extended to all categories in 2015, now protects regional sake names. Serve premium ginjo styles chilled; warm the fuller junmai, kimoto and yamahai styles, where heat raises acidity and body. Once open, refrigerate and finish aromatic grades within a week.

Shochu: Japan's distilled koji spirit

Shochu takes the sake method and adds a still. Honkaku shochu is made from a base ingredient and koji, fermented and distilled once in a pot still so that the base shows in the glass: sweet potato (imo) in Kagoshima and Miyazaki, barley (mugi) in Oita and Iki, rice (kome) in Kumamoto's Kuma valley, brown sugar (kokuto) in the Amami islands, buckwheat, and more. Awamori, Okinawa's spirit, is a honkaku shochu made from indica rice with black koji. Korui shochu is the industrial cousin, column distilled from cereals and molasses to near neutrality, and it is the base of canned chuhai.

The history runs through the Ryukyu trade routes, which brought distillation to the southern islands around the fifteenth century; a Kagoshima carpenter's complaint of 1559 is the oldest written use of the word, and a Portuguese merchant recorded rice spirit in 1546. Black koji was adopted in 1912 and white koji discovered in 1918; a reduced-pressure still in the 1970s made the lighter barley styles that carried shochu to the rest of Japan. Strength is modest, typically 24 to 30 percent. The serving styles are the point: mizuwari with cold water, oyuwari with hot water in winter, on the rocks, soda-wari, and ocha-wari with oolong, green or barley tea.

Soju: two drinks under one name

Korean soju began as a distilled rice spirit; the technique arrived with the Mongols in the thirteenth century, and Andong, a Yuan supply base, became its home. Traditional Andong soju is still made that way, a pot-distilled rice spirit bottled at about 45 percent by designated masters of traditional food.

The soju the world knows is a different thing. In 1965 the Korean government barred distilling soju from rice to protect the grain supply, and producers turned to neutral spirit distilled from sweet potato and tapioca, diluted with water and softened with sweeteners. That diluted style became the national drink, and its strength has fallen steadily: around 30 percent in the early 1970s, 25 by 1973, 23 by 1998, and under 20 for most bottles since 2007, with some now under 17. These figures come from a tertiary source and are labeled as such; the Korean Liquor Tax Act defines distilled and diluted soju separately, and that text was not available to us. Both styles are legal and both are soju.

In cocktails

Somaek is the drink Korea actually makes with soju: a shot dropped or poured into a glass of cold lager, the ratio argued over at every table. A Soju Tonic, or soju with grapefruit soda, uses the diluted style as a low-proof base. Sake works where vermouth or sherry would: a Sake Martini of gin and a dry junmai, or a Saketini with vodka, and in highballs with yuzu or cucumber. Honkaku shochu makes a Shochu Highball with soda and lemon, an Imo Old Fashioned with sweet potato shochu and brown sugar syrup, and the lightest Sour on the menu. Awamori with soda and a slice of shikuwasa lime is Okinawa's own.

Buying by style

For sake, one dry junmai for warming and for cooking, one junmai ginjo for chilled service and cocktails; buy from a shop with a refrigerator and check the bottling date. For shochu, one imo for character and one mugi for mixing, at around 25 percent. For soju, one diluted brand at around 17 percent for somaek and highballs, and one traditional distilled bottle, Andong or a modern craft equivalent, for anyone who wants to taste what the category was. Respect the strengths: sake and diluted soju are not spirits and should not be poured like them.

Folklore and fact

Rice wine is a translation error; sake is brewed from a grain, which makes it a beer in method and a wine in strength, and the industry simply calls it sake. Hot sake is a style, not a tell; the fuller junmai styles are made for it and the fragrant ginjo styles are ruined by it. Korean vodka is half true: it describes diluted soju fairly and traditional soju not at all. The 1965 policy that split the category is reported here from a tertiary source until a better one is read.

Sources

• Japan Sake and Shochu Makers Association, "How is sake made?", "How to read sake bottle labels", "How to store and preserve sake".
• Difford's Guide, "Serving and appreciating sake", "Shochu / Soju" and "Soju".
• National Tax Agency of Japan, Notice No. 19 (2015) on geographical indications for liquor.
• Japan Sake and Shochu Makers Association (honkakushochu-awamori.jp), "What is shochu?", "History of shochu", "How to serve shochu".
• Wikipedia, "Soju" (tertiary); Andong Soju producer site.