large for any statistical conclusions. Initially, the substantial error bars in the non-seeded samples indicate
larger variations in microstructure in the fat phase. This also agrees with previous findings regarding the
compactness of structure density found in properly/improperly traditionally pre-crystallized chocolate[1,
2]. The seeded samples had markedly low local diffusion rates of BODIPY; however, it is important to
note that all these samples are close to the detection limit for the applied FRAP method, which is
0.1ȝm2
/s [17]. After one week of storage, the differences between the seeded and non-seeded samples
were less pronounced, as the local diffusion rate of BODIPY in the non-seeded samples had decreased
significantly (Fig. 2(b)). The seeded samples displayed no such alteration during storage and the local
diffusion rate remained constantly low. Furthermore, no significant differences in local diffusion rate
were observed between chocolate model systems subjected to the same pre-crystallisation process i.e.
possible effects of solid particles on structure density in the fat phase could not be significantly
distinguished using the FRAP technique.
To further quantify the structure density in the various microstructures created by pre-crystallisation
and/or solid particle addition, the global diffusion properties of BODIPY were determined using HPLC.
A high capacity to retard diffusion was treated as equivalent to a dense structure. The amount of
BODIPY, expressed in ȝg of BODIPY/mg sample, as a function of distance from the cocoa
butter/BODIPY slice is presented in Figure 4. A more detailed description of the structure density results
can also be found in [16].
In the area nearest the cocoa butter/BODIPY slice, the amount of BODIPY was higher in the nonseeded
samples for both pure cocoa butter and samples with solid particles (Figure 4(a)). This indicates