If you children love cakes as much as my daughter does this is a great activity
to teach in the basics of cake making
and to get them thinking about the chemistry of cooking.
You've probably heard dad in the kitchen
late at night with the microwave but I found that what he's been doing.
He's been making these microwave mug cakes. Shall we give them a go?
Okay, these are the ingredients we need
Four tablespoons plain flour.
Two tablespoons of castor sugar.
One quarter teaspoon baking powder.
One small egg.
Two tablespoons vegetable oil.
Two tablespoons of water.
Stir vigorously with a fork.
Have we got our cake yet?No? What do you think we need to do to it
to make it into cake? Put it in the microwave?
Good plan. Before we do that, what do you think would happen
if we left out some of the ingredients?
I don't know but I think it would be kind of similar to a cake.
Do you think so? Shall we find out?
How about we could make some different batches of cake mixture and
leave some different things out? What could we leave out?
Eggs, the oil,
baking powder.
Shall we take these to the microwave?
Mixing ingredients together gets them ready to react with each other.
The microwave provides the energy needed for the chemical reactions to take place
and turn the mixture into cake.
These are the cakes. We've taken them out of the mugs,
shall we take a look? This is our first one, with all the ingredients.
What do you think of that one? Feels like a nice cake.
Yeah, and a bit bouncy.
This is the one without the egg. How does this one look?
Removing the egg made a crumbly cake. That's because the egg helps to hold
the ingredients together.
Eggs contain long chain-like molecules which unravel
and form new hard and strong structures when heated,
as you'll know if you have a fried or boiled an egg. The cooked egg forms thin layers
around the bubbles of gas,
trapping them as the cake cooks. This is the one without the baking powder.
How does this one look?
That bit has lost a bit, and that bit has collapsed.
And the top looks like a Yorkshire pudding. Removing the baking powder
gave us a cake that collapsed and isn't very spongy. This is because baking powder
contains chemicals which produce carbon dioxide gas.
this gas gets trapped in little pockets in the cake as it cooks.
This is the one without the vegetable oil. How does that look?
Finally, removing the oil from the mixture gave us a very dry cake.
This is because without the oil to coat the other ingredients,
the mixture dries out when heating.
Daddy!
Do you want to try the cake?
They look a bit different!
Because we haven't added one because
we wanted to see how they would end up.
Download our worksheet to find out more about cake chemistry.
You can send us your videos and photos and you doing this activity,
and don't forget to subscribe to find more experiments online.