Kitchen Science: How does an egg cook?

 

This one came from the question "how does an egg cook?" about a boiled egg.  Obviously you can't see inside the shell while it's cooking, so some science was necessary.  I forgot to take pictures of a lot of the process, but it should be fairly self-explanatory (hopefully!!)  

Only takes about half an hour so it's fairly quick too.

Things you need:

11 eggs
A saucepan of water big enough to fit 10 of the eggs in
Labels (we used Post-It notes) with the numbers 0 - 10 written on them
11 pots of some kind to put the eggs in
A cup and a bowl.  The cup needs to fit inside the bowl

What to do:

Boil some water in a large saucepan, once boiling, put 10 of the eggs in.  

Put the labels in the egg box, one in each space, with the unboiled egg in the space with the "0" label.

Take one egg out each minute, putting them in the correct space for how many minutes they have boiled for (boiled for 1 minute goes with label "1" etc.)

Put the cup in the bowl, I've found that even very small children can crack eggs mess-free on the edge of a cup like this.  Sometimes you have to fish shell out, but wherever the egg goes it's contained either in the cup or the bowl.  My 3-year-old has been doing this for about a year and is now brilliant at egg cracking.

Crack each egg in turn, putting the result in one of the pots, and moving the label to the pot so you know which one is which.

Look at the result and talk about it, whatever you notice is great.  We talked about how the eggs cooked from the outside in (that was really clear to see) and about why that might be, and why the egg turns from a liquid into a solid.

She then ate all the eggs that were safely cooked and gave herself stomach ache, but that's another story!