Kikkoman Corporation

This look at the sweeter side of Japanese taste and the role of sweetness in its cuisine is the first in a series of four articles on the five flavors found in Japanese food. These five basic flavors are widely accepted around the world—sweet, salty,sour, bitter and umami.

Sweet foods are a source of vitality and energy. The cells of the human body obtain energy from the breakdown of glucose, making it a kind of "fuel" for the human metabolism. Through the long process of human evolution, taste cells developed a special receptor for glucose in order to stimulate the body's appetite for this vital substance; our taste cells promote its intake by sending information to the brain, which arouses pleasure in sweetness. This receptor responds not only to glucose, which is a component of sugars, but also to some kinds of amino acids and artificial sweeteners such as saccharin.

History of Sugar in Japan

Documents show that sugar was first brought to Japan from China in the mid-eighth century as a luxury used mainly as a medicine. The primary source of sweetening in ancient times was either maltose candy or amazura ivy extract. As trade with the continent flourished from the fourteenth to seventeenth centuries, imports of sugar increased and its use expanded as a sweetener used in cooking. The practice of the tea ceremony spread among the upper classes during this period, and sweets made with sugar were developed to accompany the tea. The tradition of sweets that evolved along with the tea ceremony—virtual works of art created from sugar—form a culture of confectionery that Japan can be proud of. It was not until the eighteenth century, however, when sugar cane began to be cultivated in Japan, that sugar became more readily available to the common people.

Evolution of a Culture of Sweets

Used not only in beverages and confectionery, sugar is an ingredient in many other recipes as well. Japanese cuisine has earned a reputation for its many sweet dishes; for example, sugar is an important flavoring in sukiyaki and is often used in preparing simmered vegetables. Despite the sweetness of Japanese cuisine, the country's annual per capita consumption of sugar is unexpectedly low at about 18 kilograms, ranking Japan 95th among 155 countries (2001) and well down on the list among industrialized nations.

Japan's food culture has developed different kinds of sugar to sweeten its various foods. Sugar can be classed into two categories: one is the group of sugars including molasses, kokuto and the more refined wasanbonto which are made from boiled-down sugar cane juice. Kokuto is an unrefined dark brown sugar that is produced in Okinawa and the southwestern islands of Kagoshima; it has a strong, concentrated taste and a heavy—some describe it as "nostalgic"—aroma.

The other group comprises granular sugars such as johakuto white sugar; these are made by dissolving boiled cane juice (raw sugar) by centrifugal force which separates the crystals. Most Japanese use johakuto in their daily cooking and it can be found in most kitchens; it is considered Japan's most popular sugar.

The sizes of sugar crystals vary widely depending on the type of sugar. Johakuto has medium-sized crystals, smaller than the larger granular sugars. For the finest, most powder-like crystals, however, we must look to Japan's wasanbonto, which stands in a category all its own.

Japan's Distinctive Sweet Cuisine

Wasanbonto is a distinctive Japanese sugar with a flavor completely different to ordinary sugar, and could be called Japan's "king of sugars." For finer cuisine, Japanese use wasanbonto, which contains a small amount of molasses. Made from a domestic species of sugar cane called chikuto that is grown only in parts of Tokushima and Kagawa prefectures, wasanbonto is produced by methods passed down from the beginning of the eighteenth century.

In the traditional processing of wasanbonto, sugar cane is squeezed to extract the juice, which is gradually boiled down to a desired consistency. The condensed juice (raw sugar) is placed in a special pot to cool naturally, and is preserved in a barrel. It is then covered with cloth and placed in a box. The sugar is pressed with a stone to extract molasses, then kneaded by hand while adding small amounts of water; the sugar is then again covered with cloth and pressed. Through this repeated process of pressing and kneading, whiter—that is, more refined—sugar is produced. In the final step, the sugar is sifted and dried in the shade.

Wasanbonto has the features of both refined sucrose and cane-sugar flavors. It has long been used in Japanese-style confectionery because its very small crystals allow it to dissolve easily. Wasanbonto has the valued reputation of being of the highest quality—one reason why it is used to make the delicate Japanese confectionery higashi, which is served during the tea ceremony. In fact, certain types of higashi are made using only pure wasanbonto. Yet this special sugar is incredibly versatile: it is also used to make Western-style sweets, in coffee and tea and in general home cooking.

Mirin is another unique sweet Japanese flavoring. Often described as "sweet rice cooking wine" or "cooking sake," mirin is made from short-grain rice, glutinous rice and distilled alcohol. It contains nine types of sugars and amino acids, including glucose, maltose and trehalose and has an alcohol content of about 13 percent. Used in place of sugar to impart a subtle sweetness, mirin deepens the flavor of dishes and adds a shining texture to food and sauces such as simmered vegetable dishes, grilled fish like unagi (eel), sukiyaki and in yakitori sauce.

Sweetness and Health

Because the substance glucan produced from the breakdown of sugar can coat the surface of the teeth, causing cavities, immunology research has clearly established the connection between the increase in tooth disease and the rise of sugar consumption. Considerable advances have been made in cavity control in recent years through the dissemination of fluoride treatments and improved dental care. Obesity and diabetes resulting from the over-consumption of sugar, however, are on the rise and efforts are being made to encourage the use of non-calorie sweeteners as well as alternative types of sweeteners.

Author's Profile

Takashi Yamamoto was born in Fukui Prefecture in 1944. He graduated from the Osaka University School of Dentistry. He taught at the Faculty of Dentistry at the university from 1972 -1991. Since April 1991 he has held a professorship at the Faculty of Human Sciences there. A specialist in brain science and the physiology of taste, Dr. Yamamoto is currently engaged in research on the mechanisms of taste and eating preferences.