A good magic trick is fasinating. And this is one cool magic milk experiment you have to try. It’s a mind-blowing trick that will excite your kids and get them interested in learning more about magic, science and art.
I used simple household products to get this stunning effect. It’s so easy but the results are amazing. And this is one that can be done relatively unsupervised, if you wish, because none of the products are dangerous to kids! Though, personally, I love to see how it works just as much as the kids do.
Start with some milk, preferably room temperature, some food coloring, cotton swabs, and a little dish soap. You’ll also need a shallow bowl or plate with a lip to hold the milk.
It doesn’t matter what colors you use, but contrasting colors will be more obvious and coordinating colors will be more subtle. It all depends on the effect you want to see.
Why the Magic Milk Experiment Works
Contrary to what it looks like, milk isn’t just milk! It’s made up of mostly water, with a bit of fat in it, along with other nutrients — vitamins, minerals, proteins, etc.
The fat is in small droplets, held in solution in the water. That is, the molecules of the fat are suspended between the molecules of the water. And this fat (and the proteins) are super sensitive to changes in the milk.
When you first add the colors to the milk, they kind of “sit” on top of the milk. They might slowly spread through it, similar to paint spreading on paper.
They are held by the water tension in the milk, on the surface. So at first, it looks like not much happens.
When you add the dish soap, that’s when things start moving — literally! The soap causes a chemical reaction that makes the colors mix together and moves around in the milk.
In fact, it’s not really the colors moving, but the food coloring that allows us to see the chemical reaction between the soap and the milk fat.
What happens in the Magic Milk Experiment
The soap also lowers the surface tension of the milk, allowing the colors to mix and move about more freely. So for a bit, you’ll see everything move around and swirl, before finally settling. It’s a lot of fun to watch!
The soap reacts with both the proteins in the milk and the milk fats themselves. When the soap and proteins interact, the soap makes the proteins change shape, sending them swirling, which in turn makes the colors swirl about.
And the soap and fat want to join together in pockets called “micelles” (similar to how soap lifts the grease off your dirty pans!), so that also causes movement.
Eventually, everything reaches a balance or “equilibrium”, and the reaction ends. But the milk colors will still move about for a bit as the excess energy works its way out.
Recommended Science Experiment Books for Kids
Want more great science experiments with your kids? Check out some of our favorite science experiment books! And you can grab the instructions and materials list for this cool magic milk experiment below.
The 101 Coolest Simple Science Experiments: Awesome Things To Do With Your Parents, Babysitters and Other AdultsReal Chemistry Experiments: 40 Exciting STEAM Activities for KidsKitchen Science Lab for Kids: 52 Family Friendly Experiments from Around the HouseThe Curious Kid’s Science Book: 100+ Creative Hands-On Activities for Ages 4-8
- 1 1/2 cups of milk
- Liquid food coloring
- Dish soap
- Cotton swabs
- Dinner plate or shallow dish
- Small container
- Pour about one tablespoon of dish soap into a small container.
Pour milk onto a plate. (It’s ok if you see bubbles.)
Drip a few drops of food coloring of choice in the center of the milk. You can get creative with where you drop the drops and space them out how you wish. (Note: Food coloring may spread out slightly as pictured.)
Dip a cotton swab into the dish soap.
Place the cotton swab in the middle of the colors and watch what happens! You should see the colors start to spread out towards the sides of the plate and change over time. You can repeat this step a few times.
Tip: Kids can take their cotton swab and “draw” or “swirl” in the colors. Eventually the colors will mix together until the milk becomes one color.
If you allow the milk to sit a while before all colors are mixed completely together, you can see the milk change in neat ways as pictured here.
Watch over time how different things look!
When complete, dispose of milk in the sink.