Blogging a crystal structure a day in 2014


Contributed by

Helen Maynard-Casely

Seasons greetings. The crystal structure of Cocoa Butter

What does it look like?

Image generated by the Mercury Crystal structure visualisation software from the Cambridge Crystallographic Database Centre

Image generated by the Mercury crystal structure visualisation software

What is it?

Who'd have thought that a bundle of hydrogen, carbon and oxygen could be so tasty! Here is the structure of cocoa butter fat, one of the main tasty ingredients in chocolate. Chocolate is a very sophisticated material, and requires the right blend of sugar, milk and cocoa butter fats for it to taste right. An added complication is that you can get different crystal structures of cocoa butter depending on how you solidify it. These have different melting temperatures, so can affect the whole experience of the chocolate tasting. The type you want to have is called 'Type V' or 'Beta 2', and is why chocolate has to be tempered – to make sure you get the right type.

Where did the structure come from?

The image was generated using the structure determined by van Mechelen et al. in 2006. They used synchrotron X-rays to determine this structure and were trying to understand how fat bloom (which is, in fact, a different structure of cocoa butter, 'type VI') forms in chocolate.