How to Make Rock Candy

Guide Note: How to Make Rock Candy will teach you the secrets of preparing this very sweet treat! Its simple to make, a great project to do with your kids, and a fascinating science project! Table of Contents:

Introduction

(Creative Commons photo by Laura A.)
(Creative Commons photo by Laura A.)
  • If you ever had rock candy as a kid, you know it's a sweet, unique confection. But making it is the real fun: a dessert recipe and science project all in one.
  • The basic material of rock candy is a super saturated sugar solution, made by dissolving sugar in hot water. When the solution cools and begins to slowly evaporate at room temperature, the sugar will crystalize. A string, or specially prepared swizzle stick, will attract the crystals, forming rock candy.

What You'll Need

  • Rock candy is not a complex recipe, but does require some specific materials, many of which you may already have.

Ingredients

  1. 4 cups of Sugar
  2. 2 cups of Water
  3. Food coloring, if desired
  4. Flavor extracts, if desired

Equipment

Like diamonds and snowflakes, sugar crystallizes. (Creative Commons photo by Bu)
Like diamonds and snowflakes, sugar crystallizes. (Creative Commons photo by Bu)
  1. Saucepan
  2. Wooden spoon
    • A wooden spoon is preferable to a metal spoon, because it isn't affected by heat as easily as a metal spoon, so it will be easier to make sure the solution has a uniform temperature as you're stirring.
  3. Waxed paper
  4. Wide mouthed canning funnel
  5. Pint size canning jar
  6. A stick to support the string, such as a pencil, popsicle stick, or chopstick
  7. Cotton string
  8. A weight for the bottom of the string
    • It doesn't need to be heavy—a paper clip will do. If you'll be eating your candy, make sure the weight is clean. A small piece of store bought rock candy works very well—it will act as a seed crystal, attracting other sugar molecules and speeding the process of crystallization.

Prepare the String

  • We'll go over the string method first, then describe the extra steps involved in using swizzle sticks instead.
  1. Measure a string that reaches almost—but not quite—to the bottom of your jar.
    • If the string touches the bottom, the crystals may fuse the string to the bottom of the jar.
  2. Cut out a piece of waxed paper large enough to cover the top of the jar
  3. Poke a hole in the center of the waxed paper.
  4. Tie the string securely to the center of the pencil.
  5. Thread the string through the waxed paper.
    • Double-check the length of the string—remember, it shouldn't touch the bottom.
    • If the string is too close to the bottom of the jar, wind it around the pencil until it's about 1/2 inch above the bottom.
  6. Tie the weight to the bottom of the string.
  7. Set aside the string, stick and waxed paper.

Make a Sugar Solution

  • As with any procedure requiring boiled water, make sure that pets and small children are safely away from the stove.
The size of your rock candy is limited only by the size of the jar you use. (Creative Commons photo by Michael Surran)
The size of your rock candy is limited only by the size of the jar you use. (Creative Commons photo by Michael Surran)
  1. Pour the water into a pan and bring it to boil.
  2. Add food coloring and flavor extracts, if desired.
    • You'll have to experiment with the amount of flavor extract to use—depending on the flavor, it can go a long way.
  3. With the water still boiling, pour about 4 tablespoons of sugar into the boiling water, stirring until it dissolves.
  4. Keep adding sugar, a few tablespoons at a time, stirring well after each addition until the solution can't hold any more.
    • You'll know you've added enough when the sugar will no longer dissolve.
    • Be patient. If the solution isn't super saturated, the crystals won't form.
  5. Let the pan cool for 15 minutes.
  6. Place the canning funnel on the jar.
  7. Pour the solution through the funnel into the jar from the saucepan.
    • Make sure no undissolved sugar gets poured into the jar.
    • Stop about an inch from the top.
  8. Remove the funnel.
  9. Replace the prepared string, wax paper and weight.
    • Be sure the string hangs down in the middle of the jar.
  10. Allow the jar to cool in a safe place where it won't be disturbed.
  11. You will need to wait up to a week before the rock candy is ready to eat.

Swizzle Stick Variation

  • Rock candy makes a great treat for adults, too—as swizzle sticks for drinks. To make swizzle sticks, follow the basic procedure outlined above, but using bamboo skewers or long wooden party toothpicks instead of string. Crystals form best on a rough surface, so in order to ensure they grow on the sticks, prepare as follows:
  1. Soak the stick in water.
  2. Roll the soaked stick in granulated sugar.
  3. Let it dry.
  4. Proceed to make rock candy, as detailed above.

Watch, Wait and Enjoy!

  • It will take about 7 days for the crystals to be finished forming, but you should see them begin to take shape in less than half that time. If the weather is extremely humid, it may take a bit longer. When the crystals have formed, and you're ready to eat the candy, remove the string from the jar, and enjoy!

Subscribe to Mahalo's Weekly How To Email Newsletter

  • Get our best How To tips and ideas in your inbox each week

Resources for How to Make Rock Candy

Related Searches

Candy | Sugar | Cookware | Food Coloring | Flavor Extracts | How to Make Perfect Candy Apples | How to Deep Fry 11 Kinds of Candy



Have any great tips on How to Make Rock Candy? Post your thoughts to the discussion board.