The internal protein content value was taken as an indication of
possible differences between samples. Indeed, the values for control
samples seemed to be overestimated, with a total protein content
for the particles of 8.8% (w/w). This value was much higher
than what expected considering the swelling of the particles, as
with the change in radius (from 1.6 to 3.9 lm, a factor of 2.5) there
was a change in volume by a factor of 2.53 15. This would lead to
a protein content in the particles from 25% to 1.7%. The value of
8.8% found in this study may indicate that during centrifugation,
the particles decreased their volume. The protein concentration
of the control particles was also lower than that of the particles
similarly prepared (Sag˘lam et al., 2011), which was found to be
17%. The discrepancy can be attributed to differences in the preparation
method. In the present study, homogenization was carried
out on the oil in water emulsion system, which resulted in the formation
of smaller particles, with a higher surface to volume ratio,
and possibly, a larger extent of swelling. Protein release during
washings and centrifugation was about 14%.