Cocoa butter, also called theobroma oil, is the pale-yellow, pure edible vegetable fat of the cacao bean. It is the substance used to make solid chocolate bars. It is mixed with varying amounts of cocoa powder to produce solid pieces of chocolate. Cocoa butter is extracted from the cacao beans and can be used to make chocolate, pharmaceuticals, ointments, and toiletries. Cocoa butter has a mild chocolate flavor and aroma.
Because of the melting temperature of cocoa butter, it is often used in pharmaceuticals as a base for suppositories. It is able to be stored at room temperature, but readily melts at body temperature, releasing the medication.
Cocoa butter is one of the most stable fats known, containing natural antioxidants that prevent rancidity and give it a storage life of two to five years, making it a good choice for non-food products. The smooth texture, sweet fragrance and emollient property of cocoa butter make it a popular ingredient in cosmetics and skin care products, such as soaps and lotions.
The most common form of Cocoa butter has a melting point of around 34 to 38 degres Celsius (93 to 100 degrees Fahrenheit), 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.