Ultrasound-Assisted Cream Separation

Abstract

Ultrasonic standing waves can be applied to milks to promote the separation of cream. The mechanism for this separation arises from the acoustic forces generated in an acoustic standing wave that drives individual milk fat globules towards regions of high pressure, known as pressure anti-nodes, such that they may collect and flocculate together with increased probability. These flocculated collections of cream, may then separate from the milk rapidly due to natural buoyancy. By tuning the operating conditions and protocols employed, recent research has shown that it is possible to use these mechanisms to initiate fractionation of creams by the size of the individual milk fat globules. Ultrasonic separation technology offers an alternative methodology for cream separation that can be highly complementary to existing separation technologies currently available to the dairy industry.