Sent by Whitney, via The Kitchn's Facebook pageEditor: Whipped ganache is heavenly stuff! It never ceases to amaze us how simple cream and melted chocolate can transform into such a perfect frosting.
As we understand it, there are two reasons why ganache whips up and then sets so quickly. The first is a property of the cream. As you whisk, the fat molecules reform around the air pockets to create a solid structure - whipped cream. Read more about this in our post on why whipped cream whips.
The second reason, and why the ganache sets up so quickly, is a property of the chocolate. The cocoa butters in the chocolate crystallize and reinforce the structure of the foam. The chocolate’s dry particles also get caught up in the mix, causing the foam to stiffen further.
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