Caster Sugar & How to Use It

A type of very finely ground sugar with a texture that lands between the granulated and powdered types, caster sugar goes is also called superfine sugar and baking sugar. Although it's commonly used in the United Kingdom, it can be difficult to find in other countries. However, if you find yourself out of luck in your search for caster sugar, you can make your own.

You may wonder if you really need to use caster sugar, and the answer is: If the recipe calls for it, yes. Baking is, in a sense, a science, and how fine your sugar is can greatly affect the quality of your final product. Caster sugar, which gives baked goods more volume and a lighter texture, is also ideal for use in making meringues and sweetening tea, coffee, and other beverages. Before you grab your mixing bowls and baking pans, we'll go over what makes caster different from other types of sugars.

What is Caster Sugar?

A refined white sugar, caster sugar is most often used for baking in the United Kingdom and Australia. Many people confuse caster sugar with powdered sugar, though the two types of sugar aren't interchangeable. The main difference is that powdered sugar has been ground into a very small grain that's barely visible with the naked eye, while caster sugar is granular and has a slightly smaller grain than regular sugar.

What is caster sugar in the U.S.? While caster sugar can be found in the United States, it isn't a product you'll see in every grocery store. If you don't see anything labelled "caster sugar," look instead for "superfine" or "extra fine" sugar.

Caster Sugar Compared to Other Sugars

In baking, there are a variety of sugars available. Each type is created using different refining processes, which clean, crystallize, and dry sugar that's harvested from the two most common sugar-producing crops, sugar beets and sugar cane. Sugar can come in white, light brown, and dark brown varieties.

Caster Sugar vs. Icing Sugar

While caster sugar is a finely ground sugar with visible grains, powdered sugar is refined even further. It may also be called confectioner's sugar and, in the United Kingdom, icing sugar. As that name suggests, it's used to make most icings, as well as whipped creams and other types of confections. Powdered sugar is also typically sprinkled over baked goods, such as cannolis and funnel cakes, for enhanced taste and decoration.

Caster Sugar vs. Granulated Sugar

Granulated sugar, the most common type of white sugar, is most likely what comes to mind when you think about sugar. It's coarse in texture, which is due to refining all the naturally present molasses out of it, easy to measure, and can be sprinkled into food because its fine crystals don't bind together. The main difference between granulated and caster sugar is that granulated sugar has larger, less refined crystals. Granulated sugar can be used to bake anything from cookies to cakes, as an ingredient in sauces, and added to beverages.

Caster Sugar vs. Brown Sugar

Produced by adding molasses to granulated sugar, brown sugar comes in both light and dark varieties, though the color depends on how much molasses has been added. Light brown sugar is typically used in baking and making sauces, while dark brown sugar is used for more richly flavored baked goods. You can use brown sugar as a substitute for granulated sugar; however, you should be aware that whether you choose a light or dark brown sugar, it'll affect how much your product tastes like molasses. The main difference between brown sugar and caster sugar is texture. Brown sugar has a moist, buttery texture, while caster sugar has a finely grained texture.

Caster Sugar Substitutes

If you're having difficulty finding caster sugar in your local grocery store, you may be able to substitute it with another ingredient. Recipes that call for caster sugar will be superior if you're able to use it, but using a different type of sugar or other alternative sweetener may still yield a delicious final product. Some of these options are listed below, though you should do more research to determine whether these can be used in a 1:1 swap.

Granulated sugar: For most cake and cookie recipes that call for caster sugar, you can get away with using white granulated sugar.

Honey: Honey can often be used in place of caster sugar. Honey is denser than sugar, and it helps add moisture and chewiness to baked goods.

Muscovado sugar: This type of sugar is unrefined and has a very dark color. Unlike granulated sugar, this type is soft and moist. Its texture makes it an ideal second option for producing toffee and caramel.

Powdered sugar: Confectioner's sugar is great as a decoration for many different types of desserts. You can also use it to make confections, such as candy and fudge.

Molasses: A very dense sweetener, molasses can be used for making pies and cookies. However, it can be difficult to use at times, as it has a syrup-like consistency.

How to Make Caster Sugar

If you don't want to use substitutes for caster sugar, but still can't find any, you can always try to make your own. All you need to make caster sugar is granulated sugar and a food processor, blender, or coffee grinder. In a pinch, you can follow these steps to make your own caster sugar:

Place the granulated sugar in whichever of the above equipment you have on hand.
Pulse the sugar until it has a superfine consistency. However, be sure it isn't grinded into a powder.
Let the sugar settle for a few minutes to prevent sugary dust from shooting out when you open your blending equipment's top.
Use your newly made caster sugar or store it in an airtight container.