It is a light golden colour, with granules slightly larger than icing sugar.
It has a unique aroma and flavour, with butter and honey overtones.
It is used in making sweets and yokan, as a coffee and tea sweetener, din ipping sauces at sushi restaurants, and in baking at home.
It is manufactured traditionally in the prefectures of Tokushima and Kagawa on Shikoku island, from sugarcane. It goes through 8 stages; the entire process takes about 20 days.
A grade of the sugar called “awa wasanbon toh” is considered by some people to be the highest grade.
Its production is centred on the towns of Kamiita-cho and Donari-cho in Tokushima, where it has been made since about the 1770s.
The variety of sugarcane used is called in Japanese “chikutoh.” (The locals in the area call it “hosokiki.”) Other names for it are saccharum sinese, aka Chinese sugar cane. This variety of sugarcane grows about two yards (two metres) tall, and is about as thick as a finger. Other parts of the world use sugar cane that grows taller and thicker, as it produces more sugar.
The chikutoh sugarcane is harvested between December and February. It is harvested late in the year on purpose, to allow the sugar content of the cane to develop to its maximum.
The cane is pressed by machine to extract its juice. The juice goes into a tank; the crushed canes are used as cattle fodder, or fertilizer.
The juice is then brought to a boil and boiled for about 30 minutes. It will foam with green foam, which is removed, as it contains a bitter green lye.
At the end of the point, the juice will be light yellow coloured. It is let stand to allow sediment to settle to the bottom. The clarified juice is drained off, then boiled again to condense it, then cooled. The juice becomes a light brown. It is allowed to stand for one week, during which time it mostly solidifies into crystalline masses. These solids are wrapped in a cloth and squeezed in a pressing tub for a day to press liquid out of those solidified pieces.
The pieces are then washed and kneaded with water 4 or 5 times, to refine the sugar in them and get it whiter.
Then the pieces are dried quickly so that the sugar won’t ferment, then they are crushed, and sieved into a fine sugar.
Sources
Awa wasanbon toh. Okada Sugar Manufacture. Retrieved September 2010 from http://www.wasanbon.co.jp/wasanbon/index_eng.html
Hosking, Richard. A dictionary of Japanese food: ingredients & culture. Tuttle Publishing. 2004. Page 234 to 235.
Matsui T, Kitaoka S. Contents and compositions of the aroma in “Wasanbon” sugar. J Nutr Sci Vitaminol (Tokyo). 1981;27(6):563-72.
The World of Sugar. In Shosha Magazine. Tokyo: Marubeni. Summer 2003. Page 3.