Normally making rock candy takes days, if not weeks! It can be difficult for a small child to wait that long (though it’s great if they are willing)!
For us, not only was I dealing with an impatient little boy, but we also don’t have the room in our tiny house to just leave glasses of sugar water all over the place. I’m all about cultivating patience, but rock candy wasn’t the way I wanted to do that!
So, I decided to experiment with super saturating the water for faster sugar crystal growth… mom science for the win! While the individual crystals are much smaller than normal rock candy, due to how fast they grow, they are still just as tasty!
The Science Of Making Rock Candy
Kitchen chemistry.. my favorite kind!! How does it work? Why does the liquid turn to a solid?
Mixing the sugar with water and heating and stirring creates a supersaturated solution, meaning that there are a lot more dissolved particles sugar than water can normally dissolve and hold at a different temperature.
The hot water allows the sugar to dissolve much more quickly. This is the cool part– as the water cools, the there are more sugar particles than the water can handle! So the sugar particles are sort of “forced out” out the water, and they connect with other sugar particles. That’s what the growing crystal is!
How To Make Rock Candy Quickly
Here’s what you’ll need for making rock candy:
- 1 cup water
- 4 cups sugar
- Food coloring (optional)
- 1 candy thermometer
- 2 strings OR 2 long sticks
- Pens and clips to suspend the string/sticks in a glass
- 2 pint glasses or pint mason jars
Mix the water and sugar in a medium sauce pan and bring to a boil over medium heat. Boil until mix reaches 230°F – stirring the whole time.
**Be careful** not to boil too long or the sugar will set up too fast! Undercooking will cause the crystals to take much longer to grow.
Remove from heat. Coat the string or stick in the hot liquid, being careful not to get any on your skin. Dip the coated string/stick in granulated sugar and set aside on a plate for a moment.
This process is important, because you are giving the sugar crystals a rough surface to cling to and allow for rapid growth!
If desired, add food coloring to desired levels in the bottom of your glasses/jars.
CAREFULLY split the liquid between the two glasses/jars.
Suspend the coated string or stick into the liquid and secure with clips or pens. Make sure the string/stick is not touching the bottom of the glass, but is raised off the bottom by at least 1/2″.
Allow the glasses/jars to sit undisturbed for about 2-4 hours.
We left ours for 4 hours and the rock candy was almost as large at the glass! I would consider pulling it out after 2 hours if you want a smaller growth – and for your child to eat less sugar 😉
Remove the rock candy from the glasses/jars and suspend over a new, clean glass to drip off the excess sugar water.
If you find that the stick/string won’t budge when pulled gently – use a spoon to break up the crystals AWAY from the stick/string. You don’t want to break off all the growth from the stick/string.
Let drip for an hour or so, then enjoy as normal!
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🍬PIN THIS FOR LATER🍬
- 1 cup water
- 4 cups sugar
- a few drops food coloring optional
-
Mix the water and sugar in a medium sauce pan and bring to a boil over medium heat. Boil until mix reaches 230°F - stirring the whole time.
-
**Be careful** not to boil too long or the sugar will set up too fast! Undercooking will cause the crystals to take much longer to grow.
-
Remove from heat. Coat the string or stick in the hot liquid, being careful not to get any on your skin. Dip the coated string/stick in granulated sugar and set aside on a plate for a moment.
-
If desired, add food coloring to desired levels in the bottom of your glasses/jars.
-
CAREFULLY split the liquid between the two glasses/jars.
-
Suspend the coated string or stick into the liquid and secure with clips or pens. Make sure the string/stick is not touching the bottom of the glass, but is raised off the bottom by at least 1/2".
-
Allow the rock candy glasses/jars to sit undisturbed for about 2-4 hours.
-
Remove the rock candy from the glasses/jars and suspend over a new, clean glass to drip off the excess sugar water.
-
Let drip for an hour or so, then enjoy eating rock candy!
If you find that the stick/string won't budge when pulled gently - use a spoon to break up the crystals AWAY from the stick/string. You don't want to break off all the growth from the stick/string.
Casey Marie Ghaner says
I did this step by step and its just a gooey sludge. Did not work.
Victoria says
Hi Casey Marie! I’m sorry that happened! The sugar does turn into a gooey sludge, but you should be able to pull the stick out of it and have the rock candy attached.
A few things might have happened:
1. Did you coat the stick with sugar first? The solution needs something to stick to or it won’t work.
2. Did you add coloring or flavoring to it? Sometimes (not always) if there is *too much* of one of those things it can cause the experiment to fail.
I hope you get to try it again, maybe with just plain sugar!
Danielle says
If the experiment fails, can you add the sugar water back to a pan and heat it back up to temp and try again?
Trying now and we are not seeing any kind of growth. 🙁
Also, wouldn’t you want the mixture to cool to room temp before adding the skewer? Wouldn’t the hot sugar water melt the sugar already attached to the skewer?