OSA1 systems exhibit similar effects with a reduction of 50% in
the volume of drained liquid as the starch/protein ratio >6. Structural
stabilisation by non-adsorbing particles is most effective
when the structured particles are close to being mono dispersed
(Dickinson, 2015). Thus highlighting the mechanistic difference
behind the drastically different drainage behaviours of OSA and H.T
systems (Fig. 2). Furthermore the increase in the concentration of
H.T has a slight compromising effect on the overrun of the systems,
thus increasing the liquid fraction in the system. However the
overall volume of liquid drained is lower than the OSA systems,
even though the initial rate of drainage is greater, potentially
indicating that HT starch is retarding rates of drainage by a “corklike”
mechanism where the hydrodynamic pressure is trapping the
starch granule. Therefore no evidence of interfacial participation
suggests the HT starch may only be contributing to the overall
structural stability, where HT starch-protein networks are reducing
the overall volumes of drained liquid and maintaining the foam
structure for longer (Fig. 10).