Powdered sugar

Fine sugar with an anti-caking agent

Powdered sugar, also called confectioners' sugar and icing sugar is a finely ground sugar produced by milling granulated sugar into a powdered state. It usually contains between 2% and 5% of an anti-caking agent—such as corn starch, potato starch or tricalcium phosphate—to absorb moisture, prevent clumping, and improve flow. Although most often produced in a factory, a proxy for powdered sugar can be made by processing ordinary granulated sugar in a coffee grinder, or by crushing it by hand in a mortar and pestle.

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