Imaginative Teaching Resources & Inspirational Career Ideas from the Chilled Food Industry
We’re back in the store cupboard again – using the things we find to explore some fun food science experiments.
Cleaning coins with cola
There’s an old tradition of giving new coins at Christmas. But if you haven’t got any new copper coins (the 1p and 2p ones) it’s easy to make old dirty ones bright and shiny again.
All you need is some cola.
We found two dirty copper coins and placed them in a small bowl of cola for 24 hours. We took them out, rinsed them and rubbed with a cloth- they came out like new!
Please don’t drink the cola afterwards!
The Why?
The oxygen in the air and the copper in the pennies forms an oxide coating, this makes them look dirty. Cola is acidic and it reacts with the coating on the surface of the coins which makes them return to original shiny coating. The phosphoric acid in the cola makes it acidic and it reacts with the oxide coating that covers the coins and makes them look like the day they were minted
If you’ve not got cola you can also use tomato ketchup to make your copper coins bright and shiny again.
Take your coins and place in tomato ketchup for 24 hours. Take them out, rinse and rub them – they will be bright and shiny again!
Amazing! But why?
The oxygen in the air and the copper in the pennies forms an oxide coating, this makes the coins look dirty. When you place them in tomato ketchup, the salt and acetic acid in the tomato ketchup react with the coating breaking it down, leaving the coins shiny surface again.
Wiggly Worms
It’s the time of year for sweets – and jelly sweeties are a favourite for some of us. But how about making them come to life?? We’ve used food science to make sweetie worms wiggle around in water….
You’ll need: jelly candy worm/ snake sweets, bicarbonate of soda, water and white vinegar.
We took our small jelly snake/ worm sweets and cut them in half lengthways with scissors (you might want to get an adult to help). Then we put the worms in a glass and added 2 teaspoons of bicarbonate of soda, we then poured on enough water to dissolve and stirred, but so that the mixture was still cloudy. We stirred the mixture again, then left the worms to sit in the mixture for 30 minutes.
We poured the white wine vinegar into a clean glass, then took a soaked worm/ snake and dropped into the vinegar. Nothing happens at first but then the worm start to wiggle around like a real life worm!
How did that happen?
As you see from our potions and exploding bags, when we mix bicarbonate of soda to vinegar it creates a reaction which releases bubbles of carbon dioxide gas. The bicarbonate of soda mix has soaked into the worms, so tiny bubbles form on the surface of the worms when its dropped into the vinegar. The bubbles grow big enough to lift the worm, then the bubbles escape the sticky skin of the worm and float to the surface of the vinegar, making the worm sink back down again.
Slime-Topped Cupcakes
We aren’t the only ones who have been having fun with food science, food company Dr Oetker have created some Spectacular Science Home Baking Kits! These contain all you need to make cupcakes with a science twist plus a factsheet that explains all the hows and whys.
Tilly read through the instructions and made the cupcakes before starting to make the slime!
We made the slime by adding water to the slime mix, the slime mix contained starch, the starch particles start to swell as they absorb the water and burst. Once fully burst they thicken the water to create stretchy slime. This is a process called ‘Starch Gelatinisation’ and you can see this in action in our slime and gloop store cupboard science experiments. The slime is edible so we added to our cupcakes and ate them.
