Definition of icing sugar

The term "icing sugar" originated in the United States and Canada in the mid-19th century as a replacement for the British term "powdered sugar." In the British tradition, sugar was typically dissolved in water or liquor (such as rose water or wine) to create glazes or syrups for cakes and pastries, with no additional sugar used as decoration. In the US and Canada, however, a stylistic preference for thick, decorative sugar coats on pastries and cakes was emerging, and a finely ground sugar called "sifted powdered sugar" or "superfine sugar" became popular. This sugar, made using a milling process that pulverized the sugar grains, was further refined by adding cornstarch as an anti-caking agent to prevent clumping. This sugar came to be known as "icing sugar" as it was frequently used as a finishing touch on cakes and pastries. The use of sifted powdered sugar as a decoration grew in popularity throughout the nineteenth century, driven in part by advancements in sugar milling technology that allowed for the creation of finer, more consistent sugar particles. Today, icing sugar is a beloved ingredient in many sweet treats, from frosted cupcakes to intricately decorated cakes and pastries.