Powdered sugar has the smallest crystal size of any of the white sugars, as small as 0.01 millimeters. It’s also known as “confectioner’s” or “icing” sugar depending on where you live. The tiny crystals make it good for dusting and of course making frostings and icings. The only major drawback to powdered sugar is its flavor and texture which can be chalky. The reason, because powdered sugar contains up to about 3% corn starch, which is there to absorb moisture and keep the tiny crystals from clumping.
The brand icing sugar I get where I live is a UK product which lists E341 (Tricalcium Phosphate) as the anti-caking agent. I always used to wonder about the chalky texture I used to read about until someone brought me a bag of Domino brand confectioner’s sugar from the US. I made a simple water icing with it and compared to what I was used to it had a slightly soapy taste (if soapy is the best way to describe it) and it somehow seemed less sweet.
As an addition, in Australia we also have “pure icing sugar”, which (I believe) has no caking agent and a superior taste by far
Interesting. I don’t think we have that here. I wonder how it retains its consistency?
I’ll see if I can find out, Rick!
- Joe
Rick is correct. Pure icing sugar is exactly what it says on the label. It is powdered sugar with no additives. It goes lumpy very soon after opening so I only buy it when I have a specific need, such as royal icing. The rest of the time I use icing sugar mixture, which is powdered sugar mixed with up to around 5% cornflour. This does not go lumpy if kept in an airtight container. It is used for stuff like buttercream, sweetening whipped cream etc.
Here is a link with more information:
http://www.sugaraustralia.com.au/CrystalSugars.aspx
Very interesting, Heather. My guess is that there’s something like that available as a specialty product in the States, but I’ve just not come across it. But it’s definitely not something you see in stores. Thanks for the comment!
- Joe
On Passover, Eastern European Jews do not eat “kitniyot” (legumes), and corn products fall into this category. (It’s not really a legume, but let’s leave that aside for now.) So confectioner’s sugar for Passover is mixed with potato starch (instead of corn starch). I usually whiz some granulated sugar in the blender to make my own confectioner’s sugar if I need it for holiday baking. In small batches it keeps fine without clumping for several days, but it has to be stored airtight and I suppose climate plays a big role here. If it does clump, then it can be sifted. There really is a difference in taste.
FYI — a couple of years ago I had some confectioner’s sugar left over after the holiday and decided to make macarons. I halved the batter and put “pure” confectioner’s sugar in one batch, and “regular” confectioner’s sugar in the other. I wanted to see if the starch in the sugar really made a difference in how the macarons baked, as quite a few recipes make this claim. Now I’m no expert, but I can tell you that both batches came out with beautiful smooth shells and wonderful frilly feet. So don’t let those recipes scare ya!
Fascinating. Thanks for a very useful comment, Chana!
- Joe
King Arthur makes a “glazing sugar” that’s just confectioner’s sugar without the cornstarch. Mind you, I’ve never seen it in stores, but you can order it from their website. Since you’re a fan of their flour, I figured you might be interested.
Interesting. Thanks, Nicole!
- Joe