Ice Cream in a Can
Answers to questions found on page 6.

If you put the ingredients in a container and freeze them without mixing, what would happen?

It would freeze into one solid block... you can try it if you'd like... just don't plan to eat it!

 

Why is churning or mixing needed to make ice cream?

Milk particles are surrounded by globules of fat. These fat globules need to be broken apart so the sugar and vanilla can become part of the mixture. The churning allows the particles to mix as they freeze creating a texture that can be scooped with an ice cream scoop.

 

Why is salt put in with the ice?

Ice cream freezes at -3°C (or 27°F), but ordinary ice starts to melt at 0° C (32° F). If the tub contained just ice by itself, it would soon melt into an ice-water mixture and the ice cream would not freeze. That's where the salt comes in. Salt lowers the freezing point of water. Mixing salt with ice makes a substance that has a freezing point of -5° C (23° F), and that's cold enough to freeze the ice cream. Why the ice-water mixture has a lower freezing point is complex and requires the knowledge of advanced phsyics. Let's save that for high school!

Did You Know?
Alfalfa is a type of clover.

For more information on alfalfa check out www.calhay.org.