Micronized cocoa butter particles produced by a supercritical process

A process using supercritical CO2 has been developed to produce form V crystals of cocoa butter. In this process, solid cocoa butter is put in an autoclave in which supercritical carbon dioxide is then introduced. At high pressure, two liquid phases, one CO2-rich and one cocoa butter-rich are formed. Both of them can be sent to a depressurisation nozzle leading to particle formation in an expansion vessel. Moreover, particles can also be formed in the first autoclave undergoing slower depressurisation. Both particle populations (upstream and downstream the nozzle) have been characterised using calorimetric method (differential scanning calorimetry, DSC) and environmental scanning electron microscopy (ESEM). The polymorphism of the particles produced as well as their size and morphology show that they are potentially usable in the tempering step of the manufacturing process of chocolate.