4. Conclusions
The CLSM was found to be a good technique for monitor the cocoa butter crystallisation in chocolate
model systems during cooling. Seeded samples formed multiple nucleation sites, which induced a rapid
growth of crystals and resulted in a more homogenous microstructure. The non-seeded samples showed a
more random structure, with some areas developing large spherical crystals while other parts gained a
more heterogeneous microstructure with large inclusions of liquid fat and small compact crystals.
The structure density in the various model systems during storage could be quantified by smallmolecule
diffusion at different length scales using FRAP and HPLC. FRAP measurements gave detailed
information on the heterogeneity or homogeneity of microstructure in the cocoa butter, whereas the
HPLC indicated the impact of solid particles. Both techniques showed significant differences in terms of
structure density between the pre-crystallisation processes, seeded and non-seeded. During storage, the
non-seeded samples experienced extensive post-crystallisation and evolved towards the dense structure
found in the seeded samples. However, the initial less compact structure in the non-seeded samples
created a more favourable environment in which the global diffusion could occur.