Microstructure characterization
Differential scanning calorimetry was used to determine if
RBW was dispersed in HOSO instead of being separated from
it after the oleogel was dispersed in the ice cream emulsion. The
RBW oleogel melting curve revealed 2 peaks that corresponded
to the melting point of RBW (70.2 ◦C) and HOSO (–73 ◦C),
while the pure RBW melting curve showed the presence of only
1 peak (81.3 ◦C), which corresponded to the melting point of the
wax. When RBW is dissolved in HOSO, the melting temperature
of RBW is depressed significantly (11.1 ◦C) due to colligative
effects, that is, melting point depression, while the crystallization
temperature is depressed due to inhibition of nucleation in dispersed
systems (Hartel 2001; Coupland 2002). When the RBW oleogel ice cream emulsion was analyzed, the melting temperature
of RBW in the ice cream emulsion was similar (approximately
70 ◦C) to the melting temperature of RBW in the oleogel. The
effect of melting point depression was evident for both systems,
which suggested that in both bulk oleogel and emulsions, RBW
is in solution in HOSO.