What is caster sugar? Let’s take a look at the different types of sugars often used in baking to understand why we use them, what makes them different, and the substitutions that are available.
Today we’re taking a break from baking to talk all things sugar. (nerd alert 👩🍳)
As an Australian blogger, one of the most common questions I get asked is, ‘What is caster sugar?’ I’ve learnt that while it’s a common baking ingredient here in Australia (I use it in most of my cookies and cakes), it doesn’t seem to be readily available around the world.
So if you’ve been wondering what caster sugar is and what sugar you can use in your baking instead, you’ve come to the right place. I’ve put together the most commonly asked questions about sugar and baking (including ones that I’ve asked myself over the years) to ensure you have success in your kitchen.
What is caster sugar?
Caster sugar is a refined white sugar that is commonly used for baking in Australia and also the UK. It looks like this >
Can I use granulated sugar instead of caster sugar?
Yes. While caster sugar and granulated sugar are not exactly the same, they can be swapped 1:1 in baking recipes. Caster sugar is slightly finer and dissolves more easily, but in my experience, this doesn’t affect most baking recipes if swapped with granulated sugar.
Where can I buy caster sugar?
Here in Australia, caster sugar is sold at all major supermarkets. If it’s not readily available in your country, I suggest you save yourself the headache and just use granulated sugar or similar instead.
Can I make my own caster sugar?
To make your own caster sugar, you can process granulated sugar in a powerful food processor or blender to get a finer texture. I wouldn’t worry though as it won’t make a big difference to the final result in most baking recipes.
Why is caster sugar used in baking?
Caster sugar is often used in baking cookies, cakes, cupcakes and muffins because of it’s light texture and ability to dissolve easily. It is almost always used when baking and is rarely used raw. It is NOT used for icing, frostings or buttercream.
What is golden caster sugar?
Golden caster sugar is caster sugar that has been processed in a way that keeps some molasses (just like brown sugar), therefore giving it a slightly light brown colour and a more buttery, caramel flavour. If you don’t have it, just use regular caster sugar instead.
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What is brown sugar?
Brown sugar is a partially refined sugar that has molasses added to it – hence the brown colour. The presence of molasses gives the sugar a distinct caramel flavour.
Can brown sugar be substituted for caster sugar?
This is a tricky one. In some baking recipes yes, in others, perhaps not. Brown sugar and caster sugar are different. They produce different flavours and react differently when baked. More often than not, there’s a reason the recipe writer has chosen to use a particular type of sugar in their recipe.
It’s not to say the recipe won’t work, but bear in mind, it’s likely to alter the look and taste of the final product if you don’t use the sugars that are specified in the recipe.
When a recipe says brown sugar, does it mean light or dark brown sugar?
Good question. Here in Australia, we have a product called brown sugar. It’s most commonly used in baking and is not defined as being light nor dark. However, when compared to American-style light and dark brown sugar, I would suggest it is closer to light brown sugar. It looks like this >
What is icing sugar?
Icing sugar is a very, very finely ground white sugar, that is so fine it resembles a white powder. It is often used to make frostings or buttercream for cakes.
Are caster sugar and icing sugar the same?
No. Caster sugar is NOT the same as icing sugar. Do not substitute these two sugars for each other.
Is powdered sugar the same as icing sugar?
YES. Powdered sugar, confectioner’s sugar and icing sugar are all one and the same. Here in Australia, it’s called icing sugar.
If you have any burning sugar-related questions that I didn’t answer, please leave a comment below.
Donna says
Can you use caster sugar in making freezer strawberry jam.
Jessica Holmes says
Yes absolutely Donna!
Kathy says
Can I use coconut sugar?
Jessica Holmes says
Hi Kathy, personally I don’t have much experience baking with coconut sugar, but I’ve heard in most cases it can be swapped 1:1 for regular sugars.
Sandy says
Thank you for all the information
Ms. Greer says
Thank you for all your answers.
I want to make peanut butter bars and every recipe says use white granulated sugar, to make the cookie crust , but powdered sugar in the peanut butter…..trying to stay away from white granulated sugar, and I know it is the same as powdered sugar….
So what do you suggest to use as G.sugar (I’m thinking using Monk Sweetener) so can I use Monk sweetener as the sugar in the crust, and also in the peanut butter also? Do you think this will work? Been using Monk sweetener for several mos. and feel it is better for you than the white G. sugar…..Hope to hear from you soon…..ready to make these peanut butter bars now….the only thing that will have regular sugar will be the chocolate chips melted that I use on top, and I usually use Ghirardelli ‘s Choc. as I have not tried any other Choc’s. that I hear has no sugar…..is this true and can you recommend on for future use, because I’m sure I won’t find it here in Ohio where I live, will have to order online…..
Thank you so much…
Jessica Holmes says
Hi Ms. Greer, so glad you found this information helpful! Unfortunately, I don’t have any experience baking with monk sweetener so I really can’t say. I’m sorry!
Ron Chally says
I’m a diabetic and want to use Stevia for the chocolate cookies. What is your opinion or suggestions?
Thanks for your help
Ron
Austin, Texas
Jessica Holmes says
Hi Ron, I’m sorry I don’t have any experience baking with stevia. Might be worth experimenting though!
rob says
Hi Ron.
And yes stevia can be used. I have for coffee cakes and cookies and it is fine
Marc says
Could I use icing sugar for honeycomb (if that’s all I have available) ?
As long as I use the correct weight, will it be ok?
It ends up getting dissolved, so I can’t see any issues, but I wanted to have a 2nd opinion from someone else.
Jessica Holmes says
Hi Marc, I don’t have a lot of experience making honeycomb, but I’ve never seen a honeycomb recipe that calls for icing sugar. I think you’d be better off using caster sugar or the type of sugar your recipe suggests.
Les says
Is castor sugar the same as berry sugar?
Jessica Holmes says
Yes I believe so!
Abby says
I was wondering if I could find caster sugar on Amazon, here in the states, and, yes, but it’s expensive!
However Dominoes has something called Golden Granulated Sugar, the explanation saying it’s less.procrssrd than regular granulated sugar.
Would this be a close substitute?
Thanks, Abby
Jessica Holmes says
Hi Abby, I don’t think it’s the same although they say you can use it in place of granulated sugar. It’s less processed so it has a little bit of molasses in it (like brown sugar) which caster sugar doesn’t have. I’m not sure how big or fine the granules are. In saying that, it sounds like you could use it or regular granulated sugar in place of caster sugar in most recipes.
Liv says
Thanks Jess! This is very helpful – as an Australian using American recipes I was previously very confused, and eventually found this but your article is a great one stop shop. Fun fact, I once went looking for vegan powdered (icing) sugar, because I was baking for a colleague and that’s what was on my American recipe. Could not find it! I then discovered that in Australia before the 1980s, animal bones were used as a filtering agent for icing sugar! However, none of the major sugar manufacturers do that anymore so vegans can rejoice!
Jessica Holmes says
I’m so glad it was helpful Liv! And yes! I also stumbled across an article about that in my research. Bizarre!
Carl says
We don’t have caster sugar here in the States, but one can find “baking sugar.”
Where it clearly shines over granulated sugar is in cookies and cakes.
Jessica Holmes says
Ooh that’s interesting!
Rebecca says
Very helpful explanation. As a USA fan of the Great British Baking Show, I had wondered about the different names for sugars.
Jessica Holmes says
I love that show! So glad it was helpful!
Sharon says
Thank you for explaining this. I was searching all over for something I didn’t realize I had. I live in the United States and was looking for icing sugar but had 4 bags of powdered sugar in the cabinet.
Jessica Holmes says
Oh good! So glad it was helpful Sharon!
Maria says
Hello, we have something in the US known as “superfine” sugar that is used in some mixed drinks because it dissolves so easily and completely. Would that be the same as caster sugar?
I love your account, by the way. 🙂
Jessica Holmes says
Hi Maria, that sounds very similar to me!!
MarieK says
In the US, “superfine” and “baking/baker’s sugar” are the same as castor sugar.
Judy says
Can I use brown sugar for unrefined golden caster sugar?
Jessica Holmes says
Hi Judy, the best substitute would be regular caster sugar due to the similarities in grain size. In some cases, brown sugar may work but it would depend on the recipe.
Zeenat says
Icing sugar is not only very fine powdered sugar but it has some percent of cornflour in it, which helps to thicken the butter frosting. It absorbs the moisture and thickens the icings.
Misty says
I second @zeenat – I was based in Sydney previously and we seemed to have (1) icing sugar (which is pure icing sugar (CSR branded) – the one that’s described by @Jessica in this article and then there is (2) icing mixture – which as @zeenat has described: has some percentage of corn flour/starch in it – to prevent caking, and is great for cookie and butter frosting.
However, I’ve relocated to Singapore and by “icing sugar”, we are only able to get those with the starch included. It’s driving me crazy as I’ve got a couple of recipes that calls for pure icing sugar! However, we do get something here close to it: extra fine caster sugar. Hope everybody else around the world has better luck!