Cocoa Butter - Physical Properties

Physical Properties

The most common form of cocoa butter has a melting point of around 34–38 °C (93–100 °F), rendering chocolate a solid at room temperature that readily melts once inside the mouth. Cocoa butter displays polymorphism, having α, γ, β', and β crystals, with melting points of 17, 23, 26, and 35–37 °C respectively. The production of chocolate typically uses only the β crystal for its high melting point. A uniform crystal structure will result in smooth texture, sheen, and snap. Overheating cocoa butter converts the structure to a less stable form that melts below room temperature. Given time, it will naturally return to the most stable β crystal form. This phenomenon is taken advantage of in the polymorphic transformation theory of chocolate bloom. It is based on the fact that bloomed chocolates are always found to contain the most stable polymorph of cocoa butter. According to this theory, bloom occurs through the uncontrolled polymorphic transformation of cocoa butter from a less stable form to the most stable form.