It is thick, and looks a bit like yoghurt, though the texture and thickness can vary.
Amsake can be made from brown or white rice, or a mixture of both, or from sweet rice flour.
A fungus called “Aspergillus oryzae” is sprinkled on some cooked rice to cause fermentation. It produces enzymes that break carbohydrates down into sugars such as maltose and glucose. The rice is allowed to ferment and sweeten. This culture is then mixed with more plain steamed sticky rice and water, heated and held at a temperature of 131 to 140 F (55 to 60 C) for 8 to 24 hours. There is no alcohol in this version of Amasake.
A less expensive version of Amasake is made from the dregs (called “kasu”) left over from making sake. The rice material left over after making sake is passed through filters, broken up, and mixed with hot water, sugar and freshly ground ginger. This version of Amasake will contain a small amount of alcohol.
Amasake is used on its own as a dessert or snack, as baby food, and as a salad dressing.
A drink is made by mixing Amsake with water, heating it, and serving it garnished with a bit of grated ginger. This drink is sold by street vendors, in tea-houses, and at shrines at New Year. Instant versions of this Amsake drink are available.
Though sometimes called “Rice Milk”, it is not the same.
Amasake is about 20% glucose.
It should not be used as a milk substitute for children, as it does not provide the same nutrients.
“Ama” means sweet; “zaka” is sake (the “s” is usually changed to a “z” when used in a compound word.)