Also known as kuzuko, kuzu starch comes from the Japanese arrowroot. These kuzu roots are humongous — often growing to be larger than a large adult — and they’ve been used for medicinal purposes for millennia in Japan and China.
Kuzu starch is used in Japanese cooking along with other cuisines in East and Southeast Asia where, like all starches, it’s useful as a thickening agent.
Alongside its common usage to thicken sauces, kuzu starch is also often used in different types of wagashi sweets like kuzumochi or added to hot water to make a thick kuzu “tea.” While generally mild in flavor, kuzu starch becomes slightly sweet when stirred into the hot water, causing kuzu tea to have a different flavor along with its thicker texture than what one usually associates with tea.
As for its nutritional value, kuzu starch is high in fiber and is associated with lowering high blood pressure, regulating blood sugar, and relieving migraines and cramps, alongside many other medicinal purposes.
Uwajimaya carries kuzu starch along with other starches and flours in our baking and cooking section.