Method and apparatus for forming a head on a beverage

摘要

A method and apparatus for forming a head on a beverage using ultrasonic energy. The method and apparatus is concerned with subjecting a vessel containing a beverage to ultrasonic excitation for a pre-determined time and varying the frequency of the electrical signal to an ultrasonic device. Preferably the electrical signal is monitored to identify a peak in power, occurring at resonant frequency, to "lock on" to an optimum frequency for ultrasonic excitation.