Looking for the perfect summertime science experiment? Try making your own ice cream! We’ve probably all tried it before. I remember shaking up a bag of cream and crushed candy canes in my first grade classroom. The end result was delicious but I didn’t understand the science behind it. It’s actually pretty cool! (Pun intended.) Below are step-by-step instructions with the explanation. The recipe is for one serving.
- ½ c half and half
- 1 tbsp sugar
- ½ tsp vanilla
- 4 c ice cubes
- ½ c rock salt
- 1 gallon-sized Ziploc bag
- 1 quart-sized Ziploc bag
- Pour half and half, sugar and vanilla into quart-sized Ziploc bag and seal. Make sure you push out as much air as possible to avoid the risk of popping the bag in step 4.
- Mix ice cubes and rock salt in gallon-sized bag.
- Place the bag with half and half mixture inside gallon bag with ice. Seal the gallon-sized bag making sure to push out as much air as possible.
- Shake the bag for about 10-15 minutes. You may want to wear winter gloves or wrap the bag with a towel. It gets cold! While shaking the bag, talk about the chemical reaction that is happening. It’s the same thing that happens when you put salt on the roads to melt the ice in winter. When salt and ice mix, the freezing point of ice lowers. We are all taught that water turns to ice at 32 degrees Fahrenheit. When we add salt to the ice, however, that freezing temperature can lower to 20 or even 10 degrees Fahrenheit. The salt take heat from its surroundings to melt the ice. Salt on the road takes in the heat from the surrounding environment, but in this experiment, the salt pulls its heat from the half and half mixture. Thus the cream mixture could freeze into ice cream. The act of shaking helps the mixture to freeze more evenly and make a smoother ice cream. It also adds air into the mixture for a “fluffier” product. Yum!
*If you want an even easier way to make ice cream, check out our No-Churn Ice Cream recipe. Or better yet, try both and do a taste test!