Foam Flash (or Flash Foam) refers to the foam formation behavior of a liquid during foaming, i.e. the amount of foam produced dependent on time or energy input. The initial foam height just after foam formation is often referred to as Flash Foam in measurement methods where the observation time and energy input do not vary, for example as in the Ross-Miles method.
The term Flash Foam also often serves as a quality criterion when describing foam-forming liquids and/or the foam just after its formation. A "good Flash Foam" in this respect means that a lot of foam is produced rapidly, often in combination with other criteria such as stability.
Time-dependent measurement of the amount of foam produced
When foam height is recorded over time, the foam formation behavior during foaming is indicated by the slope of the curve. If using a stirrer, this behavior can be measured using cyclical interruptions. Measurements are then made during the stirring breaks to eliminate the influence of the vortex on the foam height result. The resulting curve (displayed yellow) shows an incremental increase with every cycle.
Surfactant solutions with rapid, strong foam formation are, for example, required in firefighting, in the field of body care or for foam cleaning. Foam Flash measurements can help optimize the formulation of liquids for such applications.