Summer Ice Slush | Simple Science

Did you know you can make your own delicious ice slush drink without the help of a freezer or a blender? My kids think it so fun to make their own slushy at home 🙂 This is the ideal kitchen science experiment to do on a hot summer day when all you want to eat is something freezing cold and delicious. With lots of those days up ahead, we hope you really enjoy this tasty slushy science!

I was inspired to make this ice slush in a bag by an activity I found in one of our favorite science experiment books, 50 Science Things to Make & Do. I love this book because it contains tons of simple science ideas with easy-to-follow instructions. Even my four-year-old can do many of the experiments on his own 🙂

Making Ice Slush

*This post contains affiliate links. Please see our disclosure policy.

We headed into the kitchen to gather the following supplies:

• One small Ziploc baggie (quart or sandwich size)
• One cup of fruit Juice (any variety should work just fine)
• One gallon-size Ziploc bag
• 6-8 cups ice cubes
• 6 Tbsp. Salt

Once we had our supplies ready we followed the instructions below to make delicious fruity ice slush. It is basically the same process as making frosty homemade ice cream!

• Carefully measure fruit juice into the small Ziploc baggie. Squeeze out excess air and zip up the baggie securely.
• Add ice and salt to the bigger baggie.
• Place the small bag into the large bag with ice and salt. Seal the large bag.
• Shake for 5-10 minutes, until the fruit juice has frozen into icy slushy goodness.
• This is the tricky part: Open up the large bag, remove the small bag and rinse it off quickly in cold water (pay special attention to rinse off the opening). You don’t want any of the salt water getting into your sweet fruit slushy!
• Eat and enjoy!

The Science of Making Ice Slush

Our Fishing for Ice experiment and Easy Homemade Ice Cream involve the same science that makes the fruit drink in this experiment turn from liquid to solid without the aid of a freezer.

When salt is added to ice it lowers the freezing point, making the salty icy mixture colder than ice alone. If you have a thermometer you can verify this fact. Pure water freezes at 32°F, but when salt is added to ice the mixture gets down to around 0°F. This is cold enough to freeze juice! Stirring the juice frequently ensures that the frozen parts mix with the liquidy parts, making a yummy slushy mix. If you leave your juice long enough it will freeze solid!