There are many different kinds of sugar that are available to the cook. A simple trip through the baking aisle in your local grocery store should prove this to you: table sugar, brown sugar, liquid sugar, sugar substitute, and another well-known sweet delight…
POWDERED SUGAR
Powdered sugar is nothing more than ordinary table sugar crystals (also known as sucrose) that have been ground down into a powder. Nothing fancy about that at all.
Powdered sugar is typically found in very smooth icings and frostings on our favorite desserts due to its very fine texture. Now there is a very simple experiment you can run at home involving powdered sugar. If you have any in your kitchen, try stirring a teaspoon of powdered sugar into a glass of cold water. Go on. I’ll wait…
In fact, while I wait why don’t I take a moment to direct you towards the four basic concepts of science which will be discussed in the near future:
Okay. Did you get a chance to mix up some powdered sugar water? If you did, you probably discovered something rather odd. Most of the powder clumped up into gummy blobs in your cup! This isn’t what happens whenever you add table sugar to water! Normally, table sugar sinks to the bottom and dissolves with a little stirring.
SO WHAT IS GOING ON?
If you read the ingredients on most powdered sugar containers you will find that a small amount of corn starch has been added. Why? If you recall from our previous discussion on starch, this amazing molecule acts like a tiny sponge whenever water is nearby. In fact, it DIFFUSES water into itself much faster than the sugar!
So when you place powdered sugar into cold water, it is the corn starch inside the sugar that globs up and forms those gummy blobs in the fluid!
SOMETHING OLD… SOMETHING NEW…
You have learned from our study of strawberries and cakes that sugar molecules have no problem dissolving easily into water. In fact, you also learned how brown sugar by itself or in cookies can DIFFUSE water into the environment very easily.
But something happens when you crush a sugar crystal into a powder…
IT’S TIME FOR A POP QUIZ!
If you were able to weigh a single sugar crystal and then crush it into a powder, would the weight of all the crushed powder change from the original weight of the sugar crystal?
If you said there would not be any change in weight, you are correct! This follows the LAW OF CONSERVATION since the same number of ATOMS can be found within the sugar crystal AND its powdered form.
This means there is more SURFACE AREA around the powdered sugar as compared to the sugar crystals. Surface area is defined as the total amount of material that can be measured around a particular object. Confused? Perhaps this will help:
Imagine having a large ball of clay in your hand and counting how many tiny beads you could stick around its surface. Easy, right? Now imagine tearing that clay ball into several smaller balls and recounting the number of tiny beads it would take to cover their surfaces.
The number of beads to cover ALL of the smaller balls of clay would be MUCH larger than the number around the single large ball!
Now let’s apply this to our powdered sugar. If you take large (I know they don’t look large, but work with me here…) sugar crystals and crush them into a powder, both the large crystal AND the powder contains an equal amount of ATOMS because none of them were destroyed.
All of this crushing removes some of the tiny spaces between the individual sugar grains. This means that more atoms of sugar can fit next to each other; therefore, a teaspoon of powdered sugar is more DENSE than a teaspoon of table sugar.
Learn more about chemistry concepts (and many more) in the Classic Science: Series for the Family and be certain to come back every Thursday or subscribe to The Blog of Mr.Q to learn more about how to teach science during breakfast, lunch, and dinner!
