Negative Pressure Induced Cavity Formation During Cocoa Butter Crystallization

Negative pressure effects appear to play an important role during crystallization of complex TAG mixtures such as cocoa butter. Crystallization conditions influence the final macroscopic sample density and the resulting gaseous phase void structure. Well-tempered cocoa butter had a relatively smooth surface, higher macroscopic density, and a closed-pore void structure. In contrast, over-tempered samples were rougher, less dense, and contained large continuous gas-filled pores. Under-tempered cocoa butter had properties between these two treatments, with a continuous, yet very fine pore structure. Since cocoa butter is the continuous phase in chocolate, negative pressure phenomena will likely have a significant influence on chocolate density and thus how it de-molds during processing.