How to make meringue – simple science

This experiment looks at how egg white ( albumen ) is transformed as it is whisked. Egg white is about 2/3 of the total weight of an egg, and is 10% protein, the rest being mostly water. To demonstrate the change in the egg white we are going to make Meringue.

 

What you need:

  • A bowl
  • A whisk
  • Baking sheet
  • 4 egg whites
  • 225g caster sugar

You can use less eggs as long as you use about 55g of caster sugar per egg white.

Instructions

  • Pre-heat the oven to 140 degrees, gas mark 1.
  • Line 2 baking sheets with parchment
  • Put the egg whites in a bowl and whisk slowly at first then faster as they expand. Once you get stiff peaks the egg whites are ready.
  • Add the sugar slowly a few tablespoons at a time and whisk after each sugar addition.
  • Place 2 heaped tablespoons of mixture onto the baking parchment, leave a gap and then repeat until all your mixture is used up.
  • Place in the oven on a low shelf for about 45 minutes. Then turn the oven off, but leave the meringues inside for a further 15 minutes.
  • Serve with whipped cream and fruit.

The Science Bit

When we whisk the egg white, two things happen:

  • The whisk creates a force through the egg white which unfolds the protein molecules.
  • The whisking also causes air bubbles to be trapped in the unfolded proteins which makes a foam.

When baked the foam hardens into meringue.

The science behind meringue

There are 24 comments

Post Your Thoughts