You and Your Students!
Vicki Cobb, Education World Science Editor
Make butter as a class activity. Learn about the science behind it.
Setting the Scene (Background)
Modern kids never see the origins of a lot of the stuff they take for granted. If you've never made butter in the classroom, you're in for a treat -- and for an eye-opening lesson in how much muscle-power it takes to turn a small amount of cream into butter. If you have made butter this way, you can put that activity into context by sharing two previous Show-Biz Science activities that teach students about emulsions:
If you have a quart jar and make butter from a pint of heavy cream, you'll make enough for everyone to taste it on a cracker. You'll want to involve the entire class in this activity, because there's going to be a lot of shakin' going on! Everyone should take a turn.
Follow the instructions below to make butter:
Behind the Scenes
Heavy cream is an emulsion. The fat is spread throughout the cream in very tiny drops. The protein in the milk acts as an emulsifying agent; it keeps the fat droplets suspended. When you shake the cream you force the fat droplets to come together. If they come together with enough force, they'll stick to each other and keep forming bigger and bigger gobs until you've got butter.
Use this activity in connection with two other activities that teach about emulsions:
There are two kinds of emulsions. The suspending liquid in an emulsion, also known as the enrober, can be either oil or water.
Cold cream, moisturizing creams, and hand lotions are all emulsions. They tend to feel like the enrobing liquid. Cold cream is a water-in-oil emulsion so it feels greasy or oily. Moisturizers and hand lotions are oil-in-water emulsions, so they will dry on your skin as the water evaporates.
Article By Vicki Cobb
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