Castor Sugar

[Ruthie789]

I have some British cookbooks calling for Castor Sugar. I can purchase it at a local store but find it quite expensive. I have been putting regular white sugar in the food blender and grinding it as a substitute. The only difference I am seeing is in a smaller crumb in my quick breads.
What are the advantages of using Castor sugar?

[Harters]

In the UK, we spell it "caster", not "castor". In terms of fineness, it's between ordinary granulated sugar and icing sugar. Main benefit is in baking where it's going to dissolve quicker - say, if you are creaming butter and sugar.

The website of one of our major producers, Silver Spoon, indicates that its fineness means more air is incorporated which means there's more volume in, say, a cake mix, meaning it will be lighter. I'm not a baker so am not sure I understand that but, hopefully, others might.

[cleopatra999]

My friend who is a baker and British/Aussie, but now lives over here, says that regular sugar is actually finer over here than there and uses our regular sugar without changing it, and with no ill effects to her recipes.

[todao]

I've have used "food processor" conditioned granulated sugar, caster (castor) sugar and confectioners sugar interchangeably for a long time. As long as you weigh it rather than use bulk measurements there's not enough difference in a recipe (except for things like a glaze, cake icing, etc.) to justify paying the higher price for the more refined grades.

[gooddog]

Confectioner's sugar is 3% cornstarch so may not be interchangeable with granulated in all applications. Another option for purchased superfine/caster is C&H Baker's sugar in the 4-lb carton - cheaper (per lb) than the 1lb Domino's boxes. Can be hard to find: some stores may not stock it year-round but get it in for their "holiday baking" displays.

[smtucker]

The advantage is that it is less gritty and dissolves more easily. However, no reason to buy it. Just buy the regular stuff and whizz it around in your food processor. The difference in texture is striking.

[cheesecake17]

It's finer, and dissolves quicker. Its used in drinks since it dissolves so easily. Domino has it in a small box labelled "superfine sugar." You can def grind regular white sugar in the blender.

[Ruthie789]

What is the advantage of using it in baking? As well could we just use Castor sugar in all of our baking recipes?