Twenty Turning Points That Shaped Shochu

In 1705 (Hōei 2), a fisherman from Yamakawa in Satsuma, Maeda Riemon, brought sweet potatoes back from the Ryukyu Islands. The purpose was to prepare against famine. As a crop that could grow even on land where rice would not, the sweet potato spread across the whole of Satsuma.

Sweet potatoes did not become a shochu ingredient in earnest until much later. But tracing why Kagoshima became a sweet-potato shochu region leads back to this one year, which had nothing to do with liquor at all. Today’s sweet-potato shochu rests on a crop that was planted as a famine countermeasure.

In 1953 (Shōwa 28), the Amami Islands returned to Japan from U.S. administration. At the time, rice shortages during and after the war had made awamori difficult to produce on the islands, while the market for brown sugar, the islands’ main product, was also shrinking. Brewing with brown sugar had arisen naturally under these conditions, and it received legal recognition to coincide with the reversion. The enforcement regulations were revised the following year, in 1954, and in December 1959 a National Tax Agency directive set the conditions for production in Amami.

The condition is that rice koji must be used in the first-stage mash. Brewing with brown sugar alone, without rice koji, would legally place the drink in a different category, not shochu. This extra step was built in as a requirement so that Amami’s brown-sugar shochu could remain “shochu.”

Wakatakeya Shuzojo in Kurume, Fukuoka, is a sake brewery founded in 1699. As sake sales fell under pressure from Western liquor, it was Hayashida Haruno, then 65 years old, who set up a separate company to rebuild the business.

The starting point was a discovery: a few drops of sesame oil removed shochu’s off-odors. That led to a method of adding sesame itself as an ingredient, and in 1978 the world’s first sesame shochu was completed. In the sense that it added a new ingredient to the list of options, this is one of the few examples of its kind in shochu’s history.

Shochu begins with making koji. And even for sweet-potato shochu, that koji had long been made from rice. Sweet potato entered only at the second-stage mash; rice koji together with sweet potato was the standard combination.

At Kokubu Shuzo in Kirishima, Kagoshima, toji (master brewer) Yasuda Nobuhisa began developing all-sweet-potato koji in December 1997, and the product was released in October 1998. By making even the koji from sweet potato, a sweet-potato shochu using no rice at all was created. Kokubu Shuzo describes this method on its own website as the first of its kind in the industry.

When brewing liquor in the warm climate of Kyushu, the greatest enemy is spoilage. Okinawan awamori had long used black koji, and the citric acid this koji produces protected the moromi (the fermenting mash) from spoiling.

In 1910 (Meiji 43), Kawachi Genichiro brought black koji mold back from Okinawan awamori and, over three years, succeeded in cultivating it in pure form. This mold, known as “Kawachi black koji,” made it possible to produce shochu without being at the mercy of the climate. It is a technical turning point that can be traced back to one person’s name.

Years later, Kawachi Genichiro found a white mutant strain within black koji: “Kawachi white koji.” White koji was easier to handle than black koji and did not blacken the distillery. Because it was easier to manage, it rapidly became the mainstream choice, and for more than half a century afterward, black koji nearly disappeared from shochu production.

Shochu brewed with white koji is said to have a milder palate. Sekitoba, made by Hamada Shuzo in Ichikikushikino, Kagoshima, uses this white koji and finishes with atmospheric distillation. This was shochu’s standard until black koji returned, as the next entry describes.

Sources differ on the year of this discovery, so this page states only that it occurred during the Taishō era (1912–1926).

Both black koji and white koji produce citric acid, which protects the moromi. Yellow koji, by contrast, is the koji used in sake, and it produces no citric acid. In the warm climate of Kyushu shochu production, this carries greater risk, which is precisely why it was avoided for so long.

Some distilleries choose to use yellow koji in sweet-potato shochu regardless. Nishi Shuzo in Hioki, Kagoshima, is one of them: it pairs yellow koji with ginjo yeast and finishes with vacuum distillation. The fruit-like aroma, unusual for shochu, comes from this choice. Within the lineage of koji, it is a third path — neither black nor white.

Since white koji spread during the Taishō era, black koji had nearly vanished from shochu production. It is difficult to handle, blackens the distillery, and takes extra labor — by rational calculation, a koji with no reason to return.

Kirishima Shuzo in Miyakonojo, Miyazaki, released a sweet-potato shochu brewed with black koji in 1998. It was an attempt to reproduce, with modern equipment, the black-koji method the distillery had used when it was founded. Black koji returned with a new positioning: a bolder, fuller-flavoured style. Against the story of ingredients running since Chapter 1, this chapter closes its own circle on koji alone.

Vacuum distillation is a method of distilling under lower-than-normal atmospheric pressure. Because it allows distillation at a lower temperature, it suppresses the heaviness and toastiness characteristic of atmospheric distillation, producing a lighter, cleaner liquor. In the early 1970s, this technique was introduced to barley shochu in Oita, and barley shochu became a liquor drunk nationwide. Over the same period, production also shifted toward using barley for both the koji and the secondary ingredient.

Some distilleries, however, moved in the opposite direction from lightness. Yotsuya Shuzo in Usa, Oita, uses naked barley rather than the common two-row barley, and finishes with atmospheric distillation. Also in Usa, Jotokuya Shuzojo makes “Usa Bouzu Dochu (Baisen),” which uses roasted naked barley in the second-stage mash. Both are choices that pursue toastiness rather than lightness.

Den-en Shuzo in Satsumasendai, Kagoshima, brought Japan’s first cask-aged barley shochu to market as a product in 1985. The technique itself had been completed in 1982.

In that same year, 1985, which marked its 100th anniversary, Kuroki Honten in Takanabe, Miyazaki, released as a standalone product a barley shochu it had been cask-ageing for use in blending with sweet-potato shochu. At the time, the very idea of ageing shochu in a cask for an extended period was unusual. Given the upper limit on color noted earlier, the longer a shochu ages, the narrower the range in which it can still be sold as shochu. This was a year when producers moved forward knowing that.

The barley shochu released by Satsuma Shuzo in Makurazaki, Kagoshima, was single-distilled base spirit aged for three years or more in white oak casks. More than a single product, it created the category of long-term cask-aged shochu itself.

If ⑩ is a record of “doing it first,” this one is a record of “establishing it as a category.”

As seen in ⑩ and ⑪, cask-aged barley shochu was commercialized during the 1980s. The attempt to age sweet potato in a cask for an extended period appeared afterward.

Nishi Shuzo in Hioki, Kagoshima, began development in 1995. Before settling on sherry casks, it also tried oak, cedar, and pine. The ingredient was sweet potato (Koganesengan), and the work involved confirming how a potato with aroma compounds different from barley would change inside a cask.

The distillery describes this undertaking by saying that sweet potato “was a root vegetable not suited to ageing,” but this is the distillery’s own account, and independent technical verification has not been confirmed. Nor has an official distillery statement on the number of ageing years been confirmed, so this page does not state a number of years.

Rokuchoshi Shuzo in Nishiki, Kuma District, Kumamoto, specializes in long-term ageing of rice shochu. The distillery states that, on average, it ships its product 12 years after distillation, and that its storage facility takes reference from the temperature and humidity of the Scottish Highlands.

This distillery has no single point where one could say, “it changed in this year.” Having continued unchanged is, in itself, its defining feature. Given the upper limit on color noted earlier, sustaining an average of 12 years of ageing while still qualifying as shochu is, in itself, an accumulation of technical choices.

A wooden pot still uses a wooden cask as the distillation vessel, which requires more maintenance than a metal one. According to the Kagoshima Prefecture Sake Brewers Association, wooden pot still distillation had nearly disappeared at one point, and its revival began in 1986. Distilleries that still use wooden pot stills remain in the prefecture today.

In that same year, 1986, at Shirakane Shuzo in Kagoshima, toji Kurose Toyomi revived handcrafted production in a stone storehouse built during the Meiji era. The distillery was founded in 1869, and the stone storehouse became a Registered Tangible Cultural Property in 2001.

In a single year, the revival of a tool and the revival of a production method happened in two separate places.

Manzen Shuzo suspended production in 1969, and in 1999 the fourth-generation head, Manzen Toshihiro, resumed it using pot fermentation in buried clay pots and wooden pot still distillation.

Equipment exists for fermenting moromi that is easier to manage, in both scale and temperature control. Even so, some distilleries continue to use clay pots buried in the ground. Each pot holds a smaller batch, its temperature is affected by outside air, and cleaning takes more effort.

Nakamura Shuzojo in Kirishima, Kagoshima, founded in 1888, has continued for six generations a process done entirely by hand, from cutting the sweet potatoes to attaching the labels. Also in Kirishima, Kirishima-cho Distillery was founded in 1911 and was formerly called Satsuma Kirishima Shuzo.

For Mori Izo Shuzo in Tarumizu and Murao Shuzo in Satsumasendai, accounts of production by hand using clay pots have been passed down by word of mouth. In the world of shochu, a fair number of production methods have been related this way, without being preserved in the distilleries’ own written records.

What this chapter’s examples share is that each distillery, aware of the more efficient method, chose a different one.

Single-distilled shochu was once legally called “Class 2” (otsurui). The categories Class 1 and Class 2 (kōrui and otsurui) were meant only to indicate a difference in production method, but the ordered characters kō and otsu — “first” and “second” — carried a force that made Class 2 read as “the inferior one.”

Enatsu Junkichi, the second-generation head of Kirishima Shuzo, proposed calling Class 2 shochu “honkaku shochu” at a meeting of the Kyushu Old-Style Shochu Council held in Hitoyoshi, Kumamoto, in 1957. His company began using the name on its own products from 1958, and in April 1962 a Ministry of Finance ordinance formally recognized the label “honkaku shochu.”

Nothing about the liquor itself was changed. This is a case where changing the name changed how the liquor was regarded.

In 1995 (Heisei 7), the National Tax Agency established labeling standards for geographical indications (GI), and Kuma (Kumamoto), Ryukyu (Okinawa), and Iki (Nagasaki) simultaneously became Japan’s first three geographical indication regions. Under this system, only products meeting the conditions set for a region are allowed to use that region’s name.

Until then, shochu’s regions of origin existed as a matter of fact but had no legal definition. From this year on, a region’s name became a protected term.

In 2005 (Heisei 17), “Satsuma Shochu” received its GI designation. There were three conditions: that it be sweet-potato shochu, that the sweet potatoes used be grown in Kagoshima Prefecture, and that production through bottling take place within Kagoshima Prefecture.

Following Kuma, Ryukyu, and Iki, designated in 1995, Satsuma Shochu received its designation ten years later.

In 2003, the combined shipment volume of all shochu categories exceeded that of sake for the first time in roughly fifty years. The following year, 2004, it also reached a peak in value. “All shochu categories” here refers to a figure that includes continuously distilled shochu in addition to the single-distilled honkaku shochu this page has otherwise discussed. Looking at single-distilled shochu alone, the timing of the shift is different.

Over these few years, the names of small distilleries such as Mori Izo Shuzo in Tarumizu, Murao Shuzo in Satsumasendai and Shiratama Jozo in Kinko also became known nationwide. As with several other entries on this page, none of the three has published details of its production method, so this page does not describe their techniques beyond what is publicly documented. The clay pots and handwork of Chapter 4 were also part of how shochu was talked about in this period.

It was also around this time that the general public image of shochu changed.

The sweet-potato shochu that Hamada Shuzo in Ichikikushikino, Kagoshima, released in September 2018 was made using a proprietary technique the distillery calls “koujuku-imo” (aroma-matured sweet potato). By fully ripening and further ripening the sweet potatoes after harvest, the technique increases a class of aroma compounds called monoterpene alcohols, producing an aroma reminiscent of lychee.

The koji of Chapter 2 and the cask of Chapter 3 were both factors that shaped the character of the liquor. Here, by contrast, a target aroma compound is set first, and the ingredient itself is designed to reach it. This is a single product that shows shochu production entering a stage where aroma itself becomes the object of design.