Blogger / 10 June, 2026 / Nanny Anita

Oil and Milk Experiment

This oil and milk experiment has been doing the rounds on social media for a long time now.  I haven’t done this particular version before, normally I have used water instead of milk.  This is also a way to use up any milk that has turned or if you are about to go away and need to finish up all the milk.

Follow my science is fun boardscience is fun board on Pinterest for more ideas.  Don’t forget to save the pin for later.

To do this oil and milk experiment you will need:

• Milk
• Food colouring
• Baby oil*
• Pipettes
• Small jars
• Sensory tray or dish

*You could a food-based oil, but I feel that would be a real waste, plus baby oil is clear which works better for this.

Pour your milk into your small jars and mix in your food colourings.  I did 6 different colours for this one and each colour had their own pipette.  I was trying to stop NC from mixing the coloured milk.

I poured the baby oil into the lid of our sensory tray so that it was completely covered without being too deep.

NC then used the pipettes to squirt the milk into the oil.  She is a little bit too young to appreciate the science behind it.  She simply enjoyed using the pipettes and making the colours mix.

For older children you can use this to explore density.  As the milk and oil have different densities and different chemical compositions (milk being mainly water and polar, whereas oil is non-polar), the liquids will naturally separate rather than blend together.

If you enjoyed this milk and oil experiment, be sure to check out my milk and vinegar experiment, DIY lava lamps, and Skittles density tower.

Pin for later: