Catherine and the Lurgan Brownies Group make butter from cream.
Catherine shows her Brownie group how to make butter and whipped cream from double cream. They explore how doing different things to cream results in different products, learning about how physical actions can affect the consistency of a substance. To make butter, they shake a jar of double cream that has been left out overnight. As they shake, they feel a change in consistency, and are soon left with a solid lump of butter and a little buttermilk. Whipped cream is made by simply whisking cold cream until it becomes foamy.
The girls learn that milk and cream are composed mainly of water and fat. The shaking and whisking causes fat globules to interact with each other. When making butter, the fat molecules break free from their globules, and join together to form butter. Whisking adds air to cream, breaking apart the fat globules. It forms protective bubbles around tiny pockets of air and changes the consistency of the cream.
Download the infosheet for more instructions and ideas. This series of ExpeRimental is supported by the Royal Society of Chemistry.