5. Physico-chemistry of foam overrun and stability

The aim is to find the right balance between formula and process parameters...

Two different bubble stabilization or trapping mechanisms are involved:

• stabilization of gas bubble interfaces;

• structuring the continuous phase.

The extent of the contribution made by either of these two mechanisms will depend on a number of factors:

• the nature of the formulation used, in particular its fat concentration and the gelling potential of the continuous phase;

• quantity of gas to be incorporated ;

• desired gas bubble size and stability time (days, weeks, months...).

When present in high concentrations in the continuous...