“Sugar is the most important molecule on earth.”
That’s the case Adam Rogers makes in chapter two of his award-winning book, Proof: The Science of Booze. And at least as far as sugar’s centrality to fermentation is concerned, Rogers has ample ammunition for his thesis. Even outside the bounds of alcohol-production, the world has many varieties of sugar that are essential to cooking–turbinado, muscovado, and demerara are some of the better-known examples. These are all dark or lightly-refined sugars that are more flavorful than the hyper-refined brown sugar used in baking in some countries. That stuff is often just white sugar with molasses added back to it.
So does Japan have a dark sugar tradition?
Yes, several actually. There’s a variety of grades and iterations that can be referred to as kokuto (黒糖 in Japanese kanji; pronounced /koh-koo-toh/). But kokuto hasn’t received as much attention as it deserves. Yukari Sakamoto’s excellent 2010 publication, Food Sake Tokyo, translates kokuto as brown sugar but Richard Hosking’s A Dictionary of Japanese Food doesn’t even grant the term its own entry (opting instead for sato, Japanese for sugar). Much like the drinks that this site is obsessed with, kokuto is still not on the world’s radar despite its quality.
As in other parts of the world, refined white sugar is commonly used in Japanese kitchens. However, there are also darker varieties sold in large clumps. Supermarkets sell everything from zarame tō (a coarse cooking sugar) to lumps of kokuto sold as snacks. Kokuto is rich in molasses, minerals, and umami, and in Japan it is considered a “healthy” sugar.
The type of sugarcane that we’re talking about is Saccharum officinarum, a hearty and tall varietal mostly cultivated in Okinawa Prefecture and the Amami Islands. Amami is a string of landmasses that are administratively part of Kagoshima Prefecture but are actually closer to Okinawa. Okinawa and Amami have a subtropical climate with adequate rainfall and almost no chance of temperatures dropping below 10° Celsius (50° F). This is ideal for Saccharum officinarum, and the islands are responsible for the vast majority of Japanese kokuto sugar production.
Brown sugar? Black sugar? Neither actually.
The high quality of kokuto, paradoxically, complicates translation into English. We’ve already established that it’s often translated as brown sugar, but some feel the term does kokuto a disservice because of its association with low-quality baking sugar. In short, calling it brown sugar might give the culinary-literate the wrong impression.
On the other hand, calling it black sugar, a literal translation, is also misleading because kokuto is actually, well, brown. It’s easy to understand how that misnaming came about if you dig a little deeper into Japan’s complex relationship with colors. The key takeaway is that color names in Japan don’t always match what your eyes perceive. (Ao ringo (lit. “blue” apple) anyone?) Here’s why.
In addition to habitually naming colors after objects in nature, there’s an affinity for the black-white binary. Most shades of brown don’t fit in the white basket, so they are called black by default. Various tints of purple and other colors too dark to be called red or blue have also been lumped together as kuro (黒 / black) for millennia. Foodstuffs like kuromai (黒米 / lit. black rice) are actually kind of purple. Kurozu (黒酢 / lit. black vinegar), which is more accurately translated as amber rice vinegar, has similarly fallen prey to this mislabeling.
The word blue (ao) is equally catch-all and amorphous in Japan (hence “blue” traffic lights), but I digress.
One thing that everyone agrees on, however, is that kokuto deserves every gram of respect that it receives. Compared to refined sugar, kokuto has far more minerals, vitamins, and protein, and also contains some alkalinity. So in order to differentiate kokuto, we may need to agree on a single, accurate phrase.
If it’s embarrassing to translate kokuto as brown sugar and fallacious to call it black sugar, then what should we call it? With respect to its inherent quality, we here at Kanpai recommend simply using kokuto or kokuto sugar. We’ve been saying for years that ‘koji’ should be used as-is in other languages, and we feel kokuto deserves the same respect. After all, kokuto’s international peers, such as the muscovado and turbinado varieties named earlier, have not been translated either. So why should kokuto be treated differently?
How is kokuto made?
The best kokuto is made from sugarcane harvested by hand with a sickle, a time-consuming and exhausting process. Each of the tall canes, which take around 18 months to fully mature, is hacked, pruned, and checked individually. And depending on the island, there are sometimes surly pit vipers in the fields which can add some excitement.
The day’s haul is then transported by truck to a kokuto factory. First, they squeeze the cane juice out. Next, they slowly simmer the juice in a series of vats until it starts to thicken.
By the end of the process, the juice becomes dark and viscous, almost like melted milk chocolate. Before it cools too much, they pour it into a mold where it hardens. It has a ‘green’ aroma–grassy notes with tinges of minerality and unmistakable molasses–but the overall flavor profile will soften within a few weeks.
Kokuto Shochu
Kokuto sugar production is an essential ingredient for the honkaku shochu industry. Amami Kokuto Shochu, a Geographical Indication recognized by the Japanese government, is crafted on the Amami Islands and must be fermented with kojified rice as well. Because it’s already rich in monosaccharides (ie. koji is not necessary as with rice), delicious molasses- and caramel-forward kokuto is added only to the second (and sometimes third) fermentation. Kokuto arrives at distilleries in boxes containing thick slabs of kokuto cake, with a texture mirroring that of maple candy, and is melted in large vats of hot water. It is then added to the fermentation after cooling.
Thanks to myriad options during ingredient preparation, fermentation, distillation, and aging, kokuto shochu can range from light, grassy, and sweet to intensely rich with notes of molasses, treacle, and aniseed, alongside deep minerality and earthiness. By analyzing kokuto sugar’s color and hardness, its quality can be sorted into five grades: special, 1st class, 2nd class, 3rd class, and other. The Kokuto Shochu Industry uses special and 1st class kokuto during fermentation.
Amami Kokuto Shochu is currently made by 28 distilleries in Amami spread across five islands. The style cannot legally be made anywhere else in Japan, even if it uses rice koji. A similar product made outside the Amami Island chain would be labeled and taxed as “spirits” (スピリッツ) under Japanese law.
Looking for some good kokuto shochu? Here’s some of what’s available internationally:
**Editor’s note: We removed macrons from most transliterations of Japanese words. For instance, kokutō, kōji, and shōchū are also correct spellings of these important words.
I had someone ask me if Kuro Sato is the same thing as Kokuto, so now I am googling around to see if it is the same thing or if kuro sato is closer to brown sugar.
Does Kokuto have other aliases ?
Great question! Sato Kuro and kokuto are completely different.
Sato Kuro is a sweet potato shochu made with black koji, which is what the word ‘kuro’ refers to.