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What are sugar crystals made of?
Question Date: 2015-04-23
Answer 1:

The regular sugar that we eat is sugar that comes from either the sugarcane (most of which comes from Brazil) or from sugar beet (mostly from Russia). It is composed of two smaller sugars, called glucose and fructose. Fructose is the sugar your fruits have, thus called fructose.

Glucose is a little hexagon made up of six carbon atoms and fructose is a pentagon of carbon atoms, and both have oxygen and hydrogens hanging off the hexagon and pentagon. They link with each other via an oxygen and make the sucrose molecule.

A crystal is a repeating pattern of sucrose molecules. So, if we put a sugar crystal in water, water molecules go in between the sucrose molecules and break the pattern - that's why when sugar gets wet it dissolves and makes a syrup.

It's not hard to get sugar crystals to grow:
You can do it from sugar syrup which you put in a clean glass jar and a string that you hang. When sucrose meets another sucrose, they like to connect and they start a little crystal. This first crystal is called a nucleus! If more sucrose molecules join them, then the crystal will grow until you eventually get sugar rock candy!

If you ever have a chance to look at chocolate milk under the microscope and under polarized light (like taking two polarized sunglasses and putting them perpendicular to each other), you will see that sugar crystals will shine! Because they can orient light. Crystals - not just of sugar, all crystals - shine under polarized light. But in chocolate milk they are also floating among fat droplets.

But what if you want to disrupt the formation of a crystal forming, just like in lollipops? To avoid making a crystal, we need to break the repeating pattern of sucrose molecules. So, we can add another sugar to frustrate them! Like pure glucose...or add fructose, in the form of high fructose corn syrup...that's why lollipops have so much high fructose corn syrup.

Keep in mind that there are also other types of sugars, like maltose and trehalose. Find them online!

Answer 2:


There are many different kinds of sugar, but the one you are probably thinking of is sucrose, which is C12H22O11 (twelve carbons, twenty-two hydrogens, and eleven oxygens per molecule).

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