When two normally immiscible liquids, that is those that are mutually insoluble, form a mixture, then that mixture is referred to as an emulsion. Emulsions consist of the particles of the mother liquids in suspended state, thus retaining their independent characteristics while existing as a smooth consistent mix that can be packaged easily.
In our day to day existence we use emulsions more frequently than we might think. Toothpastes, gels, creams, lotions, ointments, are all examples of these suspended state mixtures. They provide us with the benefit of all the individual ingredients they encase, while also being able to maintain a consistent state of matter (one that does not evaporate, shrink, separate, or undergo any other change in physical state). Often the single and most important benefit of an emulsion is the fact that one of the liquids simply forms a base for the other liquid which is the one that is required, say in the case of ointments. The required liquid alone may not be stable enough to be packaged alone. Also, the solvents for it may be harmful in some way for the skin. A non hazardous secondary liquid base is of great help in such a situation.
The typical process of creating an emulsion in bulk batches is a vacuum emulsion mixer which takes care of all the processes involved in dispersing two liquids together. The ingredients are loaded into stainless steel tanks, after which they are agitated and made to move rapidly by means of centrifugal force, thus blending and creating the required mix. Temperatures play a big part in the process, and thus provisions for heating and cooling the system by means of stem or electric current is also a major component. The electric controls are featured on a vertical cabinet situated between the tanks. The whole mixing process is conducted in an insulated space with little or no interference by manual labour, so as to prevent the risk of entry of germs, pollutants or dust. An inspection window is provided for this purpose to be able to monitor each stage without having to physically intervene.
Vacuum emulsion mixers have naturally become quite common today due to the sheer demand for the products they create, with several companies selling them over the internet. They are distinguished for quality on the basis of the quality of steel and of upper surface insulation, number of programmable presets, capacity, temperature control equipment, and so on.