Mizuame is a mucoid sweetener made by saccharifying acid and diastatic enzymes with starch. It is a mixture of glucose, maltose, and dextrin, and the main component is malt sugar. It is almost transparent in a normal state, but it becomes silver gray when it is aerated by kneading.
In ancient times it used to be manufactured by using brown rice seedlings and the diastatic enzyme it contains. In more recent years malt has been used as a supply of diastatic enzyme since it has better efficiency than brown rice seedlings (malt mizuame), it is currently manufactured by adding acid to the starch and hydrolyzing it (the acid saccharification method). The mizuame manufactured through the acid saccharification method is clear and colorless and contains only moisture and carbohydrate. However, malt mizuame contains small amounts of minerals derived from the raw material and has flavor, and its color is amber and is similar to honey. This color is the origin of amber (candy) color.
It can eaten as a candy, and there are also many ways it can be used in cooking. Before sugar came to Japan, mizuame was used as a major sweetener, but it is still used as a sweetener in making Japanese confectionery. It contains a property which interferes with sugar crystallization, so smoothness can be maintained by adding it to food with a high sugar concentration. Also, it is sometimes used for coating Japanese confectionery and for moisturization. In macrobiotics it is frequently used as a sweetener in place of sugar, so the demand is increasing abroad.
The Chinese herbal drug, koui, which is the dried powder of malt mizuame made from sticky rice as a raw material, is said to have nutritional fortification and promotes a healthy stomach.
Regarding its origin, it seems that glycated starch has been used to make alcoholic beverages since prehistoric times. One theory has its origin in Kyoto, but the detailed process and place are still unknown.
Mizuame came with the kamishibai (picture-story show) that had been popular until the 1970s, and children played with mizuame by stirring it with throwaway chopsticks and ate it as a snack.
A filling of mizuame inside Nanbu Senbei (Nanbu rice crackers) is known as 'amesen.'
In the story of Ikkyu san, Ikkyu found Osho (a priest)'s treasured mizuame and ate the whole thing while he was out, and his story about making an excuse was famous, and its content is similar to that of "Busu" of kyogen (a farce played during a noh play cycle).