At home for 5-11 11-14
- Level Elementary
What you need
- Two glasses
- Skimmed milk
- Whole milk
- Two straws
- A friend
- Pour about five centimetres of skimmed milk in to one glass and the same amount of whole milk in to the other glass
- Both starting at the same time, blow through the straws and into the milk
Results and Explanation
The skimmed milk froths up much faster than the whole milk, and the bubbles last longer too!
Bubbles can form in milk because the milk proteins form a strong skin. But the fat in whole milk interacts with these proteins, weakening this skin and popping the bubbles.
These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.