Activity

Butter

Summary
Make butter from cream. Discuss states of matter or colloids at each step.
Science content
Chemistry: States of Matter, Properties of Materials (K-7)
Chemistry: Physical Changes, Solutions, Mixtures and Separating (2, 4, 5, 6)
Materials
  • whipping cream, to fill each jar 1/3 way
  • jars to shake in, about one per 6 students
  • dixie cups for tasting buttermilk
  • plates for butter
  • salt to add to butter
  • knives to spread butter
  • crackers to eat butter on
Procedure

Add the whipping cream to each jar.
Students in a circle, shake the jar, then pass it on.
Shake until the cream is whipped (see first photo), then shake more to separate the fat and buttermilk (see second photo).
Pour out the buttermilk to taste.
Dump out the butter, add a little salt, and eat on bread or crackers.

For a lesson on states of matter, the students point out when they find a state during this activity, whether an ingredient or a new state from a reaction.
Discuss the changes in states of matter while making butter: start with a liquid (cream), which becomes a foamy solid (whipped cream), which then separates into a solid (butter) and a liquid (buttermilk).

For older students, work through the steps of how the molecules are arranged in the cream and butter.

For a lesson on mixtures, every step of this activity is a different type of colloid is formed:
Cream is an emulsion (drops of liquid fat in liquid water)
Whipped cream is a foam (air bubbles in the liquid cream)
Butter is a gel (liquid water droplets in solid fat)
See attached mixtures file for examples of other colloids, and other types of mixtures.

(Song used while shaking with younger students, to the tune of "Row, row, row your boat":
Shake, shake, shake the cream,
Shake it in a cup,
We are making butter now,
Then we'll eat it up)

Attached documents
Notes

Milk can be looked at under the transmission scope to see the fat droplets. Do the same for whipped cream and butter?

Grades taught
Gr K
Gr 1
Gr 2
Gr 3
Gr 4
Gr 5
Gr 6