The presence of HT starch has littl

The presence of HT starch has little effect on the surface tension
of the systems, but a slight increase is observed for 0.5wt% protein
systems Fig. 4, which is reflected in an overrun compromise of
~20%. Furthermore it is reported that polydispersity (Fig. 2) of
particles in wet foam systems can lead to dramatic reductions in
foaming capacity (Dickinson, 2015). It was observed with Silica
particles, that as the film thickness approaches the size of larger
particles, they become pinned, constraining their diffusivity leading
to a subsequent osmotic pressure gradient. This gradient will draw
water from regions rich in larger particles thus thinning the film
around the particle leading to rupture (Dickinson, 2015). Moreover
the non-uniformity of particles surface, has been shown to cause
piercing of the air-bubbles thus acting as an anti-foaming agent
(Hunter et al., 2008) as indicated by the overrun reductions shown
in Table 2. The H.T starch will form a different mixture with the
protein. The larger area and the highly branched structure means
that coacervation or phase segregation and even complexation can
occur.