The understanding of foam
Foam is a mass of bubbles created when certain types of gas are dispersed into a liquid and the dispersion is then stabilized. High- strength films of liquid surround the bubbles, forming large volumes of non-productive foam. While the actual cause of foam is a complicated study in physical chemistry, its existence presents serious problems in both the operation of industrial processes and the quality of finished products. If not properly controlled, foam can reduce equipment capacity and increase processing time and expense.
Foam can be controlled by making basic changes in the process itself or by using mechanical defoaming equipment. However, chemical defoamers have proven to be the most effective and economical.
An effective chemical defoaming agent must meet the following requirements:
Possess lower surface tension than the system to which it is added
Disperse readily in the system
Possess poor or low solubility (incompatibility) in the system
Be inert
Leave no substantial residue or odor
Meet FDA and USDA requirements where applicable
Be certified Kosher and Pareve where applicable
These requirements are met most effectively with silicone antifoams