10 - Noncocoa Ingredients on Cocoa Butter Crystallization

Abstract

The crystallization process of cocoa butter in chocolate is crucial to achieving the correct crystal form. Besides processing, the crystallization behavior of cocoa butter in chocolate is also affected by particulate solids, foreign fats (e.g. milk fat), and emulsifiers, which offer additional nucleation sites and/or steric hindrance to crystal nucleation and growth. This chapter discusses the effect of non-cocoa ingredients in chocolate, i.e. sugar, milk powder, and emulsifiers, on the crystallization of cocoa butter. The non-cocoa ingredients in chocolate, i.e. sugar, lecithin, and milk powder, influence the crystallization of cocoa butter. Of the three ingredients, the effect of milk fat is the best documented. Although the exact mechanisms remain unknown, milk fat has been found to retard cocoa butter crystallization, delay transformation into higher melting polymorphic forms, and exhibit anti-bloom effects. Microscopy studies have shown that sugar particles do not reduce the induction time for static cocoa butter crystallization except in the presence of an emulsifier, while rheological investigations have reported the opposite effect of plain sugar enhancing crystallization.