Save the apple!

Save the apple!

Can you stop an apple going brown?

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Save an apple...

Have you ever sliced an apple and forgotten about it? Or left an apple core? They go brown and yucky.

You can save an apple! How? With a lemon, a fruit lifesaver.

What you need:

  • Apple
  • Knife
  • Lemon juice

Apple core brown_94713568

Brown apple core

How to:

Ask an adult for help using a knife.

  1. Cut the apple into quarters.
  2. Squeeze lemon juice onto two of the quarters. Make sure they're well covered.
  3. Leave the apple quarters for a few hours.

What's happened to the apple quarters?

The pieces without lemon juice on will probably be brown. The other two pieces will probably look a lot tastier. If the pieces with lemon juice on have started to go brown, try using more lemon juice next time.

What's happening?

When you cut the apple, you damaged some of its cells. Liquid from the apple cells reacts with oxygen in the air and turns brown. This is oxidation.

Vitamin C and citric acid both prevent oxidation. Vitamin C reacts with the oxygen and prevent the oxygen reacting with the apple. Citric acid makes the apple more acidic, which prevents oxidation. This means that the apple doesn't turn brown.

What other fruit and vegetables can you try this on? Have a go with bananas, pears and potatoes.

Did you know? Rust is a type of oxidation. Oxygen from the air reacts with iron to form iron oxide, which is rust!

Curriculum information

  • Summary

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    Curriculum key wordsOther web links
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