Awamori: Okinawa's rice spirit, black koji and the aged kusu of Ryukyu

Awamori is Okinawa's distilled rice spirit: Thai rice, black koji, a single pot-still distillation, the Ryukyu GI and kusu aged in clay jars by shitsugi.

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^{OKINAWA'S DISTILLED RICE SPIRIT FROM THE RYUKYU COURT TO TODAY}

Low red-roofed distillery building with clay jars beside a lawn under blue sky — The Sakimoto Awamori Distillery near Ryukyu Mura, Okinawa, 2024. Image: Yuet Man Lee, CC BY-SA 4.0, via Wikimedia Commons

Awamori is a distilled spirit made in Okinawa Prefecture from long-grain indica rice, black koji mould and water, mashed once and distilled once in a pot still. Japan's National Tax Agency protects it under the geographical indication "Ryukyu", designated on 30 June 1995, which requires fermentation, distillation, storage and bottling to take place in Okinawa. Its methods are thought to have reached the Ryukyu Islands through trade in the 15th century. Awamori aged for three years or more is called kusu and is matured in earthenware jars, topped up from younger stock by a method called shitsugi.

^{WHAT IS AWAMORI AND HOW IS IT PROTECTED?}

The National Tax Agency (NTA) lists "Ryukyu" among Japan's geographical indications for spirits, with Okinawa Prefecture as its defined area and 30 June 1995 as the date of designation. Its production standard sets the rules. Only rice koji made with black koji mould belonging to Aspergillus luchuensis may be used, and the water must be collected in Okinawa. The moromi, the fermenting mash of rice koji and water, must be distilled in a pot still. Fermentation, distillation, any storage and bottling must all take place in Okinawa.

The NTA's English text refers to aged awamori as "aged shochu", placing it within Japan's wider family of distilled spirits. The Japan Sake and Shochu Makers Association separates it from other shochu by its materials and method: hard, slender Thai rice of the indica type, a black koji mould native to Okinawa, and a mash made entirely from koji that is distilled as it is. The association also notes that many awamori products are stronger than other shochu, with some bottled at up to 43 per cent alcohol. It describes long-aged kusu as having a distinctive fragrance and a rich, rounded taste.

^{WHERE DID AWAMORI COME FROM?}

Hand-drawn map of a chain of islands in coloured patches on pale paper — Map of the Ryukyu Kingdom, second half of the 18th century, Okinawa Prefectural Library. Image: Unknown cartographer, Public domain, via Wikimedia Commons

The origin of awamori is debated. The NTA says only that its techniques are said to have been introduced more than 500 years ago from South-east Asia or the Chinese mainland, through trade and cultural exchange. The Japan Sake and Shochu Makers Association says the method is thought to have come from Siam, present-day Thailand, in the 15th century, together with the spirit itself. Visit Okinawa Japan, the official travel guide of the Okinawa Convention and Visitors Bureau, places the arrival in the late 15th century, through trade with the Kingdom of Siam, during what it calls the Golden Age of the Ryukyu Kingdom.

The Japan Sake and Shochu Makers Association also cites the Joseon Sillok, the annals compiled by the Joseon court, which record that in 1477 islanders from Jeju who had drifted to Ryukyu saw clear liquor, cloudy liquor and "southern barbarian" liquor in Naha. It reads the clear liquor as awamori. Under the Ryukyu Kingdom, according to the Okinawa Awamori Distillers Association, production was controlled by the royal government and limited to three districts of Shuri: Akata, Sakiyama and Toribori. Visit Okinawa Japan adds that the spirit was reserved for the upper classes and used as prestigious gifts, and that Shuri, the seat of government, had abundant pure water.

Okinawans traditionally called the drink saki. The name awamori first appears in 1671, in a list of gifts sent by King Sho Tei of Ryukyu to the fourth Tokugawa shogun, Tokugawa Ietsuna; before that it was written as shochu. The distillers' association records four theories for the name. The historian Iha Fuyu linked it to millet, awa, used in distillation. Others point to a Sanskrit word for alcohol or to a name coined to tell it apart from Kyushu shochu. The fourth refers to foam, awa: distillers poured the spirit from a height into a cup and judged its quality by how fine and lasting the bubbles were. The writer Hagio Toshiaki considers the foam theory the most likely.

^{WHY IS AWAMORI MADE FROM THAI RICE?}

Workers washing rice at stone tanks inside a wooden building, black and white — Washing rice for awamori, Okinawa, 1930. Image: Unknown photographer, Public domain, via Wikimedia Commons

The Okinawa Awamori Distillers Association says records of the rice used in the kingdom period are unclear. Until the mid-Meiji period the main imported rice was Chinese or Korean, known as tomai, and millet was still mixed in. When tomai became expensive in the late Meiji period, distillers turned to rice from Vietnam, Myanmar, Taiwan and elsewhere in Asia. A 1924 book by Tanaka Aiho records that by the late Taisho period millet had almost disappeared from the mash. Thai rice imports began in the late Taisho period, and by the early Showa era Thai rice was the established raw material, used by all distilleries since.

The association gives three practical reasons for the choice. The hard grains stay dry and separate, which makes the koji-making stage, when black koji mould converts the rice starch, easier to handle. Fermentation after water and yeast are added is easier to keep at the right temperature. Thai rice also produces more alcohol than the other rice that was available when it was adopted. The Japan External Trade Organization (JETRO) says most awamori is still made from long-grain indica rice from Thailand, although some producers have begun to use rice grown in Okinawa.

^{HOW IS AWAMORI MADE WITH BLACK KOJI?}

Rows of large clay jars under a timber framework, black and white photograph — Jars of moromi in awamori production, Okinawa, before 1946. Image: Unknown photographer, Public domain, via Wikimedia Commons

Black koji is the defining ingredient. The NTA notes that the name of the species, Aspergillus luchuensis, comes from Ryukyu and that the mould has been designated a National Fungus of Japan. Black koji produces a large amount of citric acid, which the NTA says helps maintain sound fermentation in Okinawa's hot, humid subtropical climate. JETRO adds that the acid protects the moromi from spoiling, which allows awamori to be made all year round, and describes awamori as the only product in the world that uses black koji alone to convert rice starch into sugar.

The method is called all-koji mashing: all of the rice is turned into koji, then water and yeast are added and the mash ferments. JETRO notes that mashing and distillation each take place only once. The Japan Sake and Shochu Makers Association describes the fermented mash being distilled as it is, and the NTA standard requires a pot still. The water also shapes the spirit: the NTA describes a "Ryukyu limestone belt" running through Okinawa that yields hard water rich in minerals.

The type of distillation shapes the aroma. According to the NTA, distillation at atmospheric pressure gives a pleasant aroma, while distillation at reduced pressure gives fruity notes such as apple and banana. The NTA notes that the spirit can exceed 40 per cent alcohol straight from the still, and JETRO gives 30 to 40 per cent as the usual strength of bottled awamori. High-proof awamori is called hanazake. The Japan National Tourism Organization (JNTO) says the hanazake of Yonaguni island reaches 60 per cent and is traditionally drunk neat.

^{WHAT IS KUSU, THE AGED AWAMORI?}

The NTA, the Japan Sake and Shochu Makers Association and JETRO all define kusu as awamori aged for at least three years. JETRO says that since August 2015 all the contents of a product labelled kusu must have been aged for at least three years, and that a blend of several kusu must state the shorter ageing period of the younger spirit. The NTA describes aged awamori made by atmospheric distillation as combining a sweet vanilla aroma with the scent of matsutake mushrooms.

The NTA notes that awamori is stored in jars and bottles rather than barrels and that it continues to mature after bottling. JETRO explains that spirits such as whisky take flavour from the wood of the cask, whereas awamori matures through its own components. The Japan Sake and Shochu Makers Association says the spirit is usually stored in earthenware jars, kame, of the kinds called nanban-yaki and arayaki. In JETRO's description of shitsugi, jars are kept in order of age; when spirit is drawn from the oldest, it is refilled with the same amount from the next oldest, and so on down the line.

The Okinawa Awamori Distillers Association says the oldest publicly known kusu in Okinawa is a spirit of about 150 years held by Shikina Shuzo, which also keeps kusu of about 120 and 90 years. In the association's account, the distillery's president, Kenji Shikina, cautions that the history passed down to him by his predecessor may not be accurate. A group founded in 1997 to make 100-year kusu lays down 300 bottles of one sho each year, to be opened after a century; the association reports that more than 8,000 people had joined.

^{AWAMORI DISTILLERIES IN OKINAWA}

JETRO counts 47 distilleries and one union, spread across Okinawa's main island and the islands of Kumejima, Miyakojima, Ishigakijima and Yonagunijima; JNTO puts the total at about 50. Kamimura Shuzo was established in 1882, and JNTO notes that visitors can make a souvenir bottle that is stored in its cellars for five to ten years. Zuisen, established in 1887, stands in Sakiyama, one of the three Shuri districts permitted to make awamori under the kingdom, according to Visit Okinawa Japan. Visit Okinawa Japan describes its Seiryu as a fine and sweet kusu.

The Awamori-kan, run by its curator and president Akiyoshi Miyagi, holds awamori from all 48 of the prefecture's distilleries, covering 200 brands and 1,000 varieties, according to Visit Okinawa Japan. On 5 December 2024, "Traditional knowledge and skills of sake-making with koji mold in Japan" was added to UNESCO's Representative List of the Intangible Cultural Heritage of Humanity. Niigata University's sake studies site notes that the inscription covers sake, shochu, awamori and mirin, traditions that developed according to the climate and environment of each region of Japan.

^{HOW IS AWAMORI DRUNK?}

Four ceramic cups of clear spirit on a wooden tray with an orchid — Four types of awamori at a sake tasting, Tokyo, 2006. Image: yajico, CC BY 2.0, via Wikimedia Commons

In Okinawa, according to JNTO, awamori is usually served as a set with ice and water, so that drinkers can dilute it to their own taste; it can also be mixed with hot water. JETRO also suggests mixing it with soda, and recommends drinking aged kusu straight or on the rocks. JNTO lists Okinawan dishes that commonly accompany awamori, among them tofuyo (fermented tofu), umibudo (sea grapes), goya champuru and mozuku seaweed, and notes that drinking is often accompanied by sanshin music.

Because awamori is colourless, JETRO describes it as a versatile cocktail base and an excellent match for citrus such as shekwasha, the flat lemon grown in Okinawa. Distillers also make flavoured versions. JNTO lists versions containing shikuwasa, as the same local citrus is also spelled, and others made with coffee milk. Other forms are more particular: habushu is bottled with a pit viper steeped in it, and koregusu, awamori infused with small chilli peppers, is used as a condiment for food.

^{HENSHIN AT THE WESTIN JAKARTA}

Henshin is a Nikkei restaurant and rooftop bar on floors 67 to 69 of The Westin Jakarta. It opened in 2017, and Silverfox Studios designed the interiors of all three of its floors together with its arrival tunnel. The name henshin means transformation. In awamori, black koji mould is grown on Thai rice, the moromi ferments with Okinawan water and yeast, the mash is distilled once in a pot still, and the spirit must spend at least three years in jars or bottles before it can be sold as kusu.

On level 69, a large bingata pattern covers the ceiling. Elsewhere in the venue, translucent forms shaped like sake barrels are lit in blue. Barrels play no part in ageing awamori: the NTA notes that the spirit is stored in jars and bottles rather than barrels, and the Japan Sake and Shochu Makers Association names the usual earthenware jars as nanban-yaki and arayaki. Where kusu is kept by the shitsugi method, those jars stand in order of age, and each one drawn from is refilled from the next oldest, as JETRO describes.