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Learn some fluffy and delicious chemistry by following this marshmallow recipe.

Safety: Use clean hands and equipment. Take care using hot water and electric beaters. Ask an adult for help.

You will need

Ingredients

• Butter
• Icing sugar
• Hot and cold water
• Gelatine powder
• Vanilla essence
• Desiccated coconut (optional)

Equipment

• Deep dish
• Medium bowl
• Small bowl
• Measuring cups and spoons
• Electric beaters

What to do

1. Rub the inside of your dish with butter, and sprinkle a bit of icing sugar inside.
2. Put 2 cups icing sugar, ½ cup cold water and 1 teaspoon vanilla essence into a medium bowl. Mix for a few minutes using electric beaters. If your arm gets tired, stop and take a break before continuing.
3. Measure 1 tablespoon gelatine powder into a small bowl, and then add ½ cup hot tap water (not boiling). Stir for a minute, and then scoop out any big lumps.
4. Add the contents of the small bowl to the medium bowl. Beat for a few minutes until the mixture goes white and thickens.
5. Pour the mixture into your dish and spread it out.
6. Put the marshmallow into the fridge until it sets.
7. Cut your marshmallow into pieces. Roll the pieces in coconut or icing sugar so they don’t stick together. Enjoy!

What’s happening?

There aren’t many ingredients to marshmallows, but each ingredient is key to making it all work.

Gelatine is made from collagen, a protein that also helps hold your bones, tendons and cartilage together. It’s really good at holding things together and staying flexible. Gelatine has a slightly different chemical structure so it melts just below your body temperature – which is why marshmallows melt in your mouth, but the cartilage in a nose does not!

The sugar gives a marshmallow its sweetness, and it helps thicken your mixture. It may also help the marshmallow trap and hold onto air bubbles.

Sugar is also important if you later want to toast your marshmallows over a campfire (with adult supervision). The brown colouring and caramel taste comes from sugar molecules breaking down and recombining into caramelans, caramelens and caramelins – no joke!

Air is the secret hidden ingredient. Air is softer and more squishable than water. That’s why marshmallows are more pillow-like than regular jelly!

This activity was first published in Double Helix magazine, Issue 21. Past issues of our magazine are available for purchase.