gel particles at the oil droplet surfaces and/or due to a possible
increased viscoelasticity of the emulsions in the presence of interactive
microgel particles (Dickinson, 2015).
To estimate aggregation and coalescence of emulsion oil droplets,
the particle size distributions of the emulsions were monitored
for 4 weeks. Similar results were obtained for SPI Sus and SPI Gelbased
emulsions (Fig. 8a and b). The initial mean particle diameter
of the SPI Sus and Gel emulsions decreased with an increase of
protein content up to 3 wt% but plateaued out above it. Significant
particle size changes were not clearly observed for both the SPI
emulsions with and without prior ultrasonic treatment, demonstrating
that aggregation and coalescence of the SPI Sus and Gel
stabilized oil droplets did not readily occur under the test
conditions.
The initial mean particle diameter of the LMW-SPI Sus and Gelbased
emulsions changed depending on the protein concentration
and it was slightly different for each set of emulsions (Fig. 8c and d),
whereas the non-gelled proteins and gel particle sizes of LMW-SPI
were almost the same (Table 1). Although the detailed mechanism