It’s hot and the kids want a cool treat. With this recipe for homemade ice cream, you can satisfy that sweet tooth and learn a lesson in science at the same time.
Ice cream starts with milk --or cream-- a little sugar and a splash of vanilla. But how do those three simple ingredients turn into a bowl of goodness you eat with a spoon?
Put your liquid ingredients into a sandwich Ziplock bag and seal it up tight. Next, add several cups of ice to a gallon Ziplock bag. Now for the science… add salt to the ice and shake it up. Then put the tightly sealed Ziplock with your milk mixture inside the gallon bag, seal it up and shake it. You may want to wear gloves or oven mitts for this part, or pass it around. After five to seven minutes, feel the liquid bag. You will discover it is no longer a liquid, but a solid! It has become ice cream!
Wipe the salt water off the bag and enjoy your experiment with a little chocolate sauce or the topping of your choice.
We all know that when a liquid freezes, it becomes a solid. The science lesson here is what happens when you add salt to the ice. It lowers the freezing point and makes your ice cream possible because the ice is colder with the salt added.