Whipping profiles were obtained for all the individual systems.
This was done with the intention of maximising the air-phase
fraction within each formulation and to ensure that all systems
are within the wet foam boundary Fig 5. This ensured an unbias
comparison of the foam systems. Foam structure is dependent on
the liquid fraction (fl). Only at fl > 5%, the foam can be described as
a wet foam. Above a critical liquid fraction of f
l the bubbles no
longer touch and it is no longer a foam but a suspension of bubbles.
f
l ~ 0.26 for ordered 3D and ~0.36 for disordered 3D foams (Cantat
et al., 2013).