The Role of Emulsifiers on the Crystallization of Cocoa Butter and Cocoa Butter-sugar Blends

The crystallization of cocoa butter and 1:1 cocoa butter-sugar blends containing 2 wt% emulsifier was investigated. The emulsifiers studied were soy lecithin, polyglycerol polyricinoleate (PGPR), citric acid esters of mono- and diglycerides (CITREM) and ammonium phosphatides (YN). Lecithin, CITREM and YN enhanced nucleation and growth events substantially, however, had minimal effects on the form IV-to-V transition and enthalpy. PGPR showed a modest enhancement of crystallization kinetics but promoted the formation of form V polymorph similar to that of canola and castor oil. In the presence of sugar, emulsifiers were no longer able to influence nucleation and growth. Sugar also hindered the form IV-to-V transition in the presence of both emulsifier and oil. Overall, results showed that emulsifiers may be used to tune the isothermal crystallization of cocoa butter, though this depends on the presence of dispersed sugar.