Swirl milk in a bottle without touching it
The aim of this science fair project is to create a swirling effect in milk without touching it.
- One glass of non skimmed milk. (This experiment will work better with milkof higher fat content.)
- Food colours
- Vegetable oil
How to do the experiment:
- Without any disturbance, keep the glass of milk on the table.
- Add single drops of coloring materials followed by a drop of vegetable oil. Make sure that you add them without causing disturbance to the milk. For this let the drops slide down on the inside of the glass bottle to the milk.
- Observe after a short time, the colours swirl and mix. We can try the same experiment with different fat percentages and can watch how it affects the patterns or rating of swirling.
We know that oil is soluble in fat but not in water. Since only small amount of fat is present in milk, it is considered mostly as water. So for some time, the oil will remain over the water contained in the milk. Then the fat present in the milk will start dissolving the oil and this will cause a current, which in turn results in the movement of colours around and it causes the swirl.