Kitchen Chemistry: Jelly

Why is a jelly wobbly?


JellyJelly is a pretty fun thing to eat. It’s colourful, tasty and wobbly – and packed with chemistry!

Jelly gets its name from one of its ingredients – gelatine. And gelatine contains molecules of protein.

If you put some jelly cubes in warm water it dissolves, becoming a type of mixture known as a solution.

When you put this into the fridge, protein molecules tangle up as they get cooler – and this traps the water to make a solid. It can be fun to add fruit to the jelly – but be careful what fruit you choose.

PineapplePineapple and kiwi fruit contain a chemical called an ‘enzyme’ – this breaks up the protein molecules so the jelly won’t be able to set – it will stay sloshy – disaster!

But here’s a tip – if you use tinned pineapple, your jelly should be okay. It’s juice would have been heated up and that will have stopped the enzyme.

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