Ultrasound

Sound and other vibrations at ultrasonic frequencies — generally any acoustic wave above the normal human hearing range, i.e. above 20,000 hertz, though practical use usually means much higher frequencies tuned to the task. Food science uses ultrasound two ways: high-power ultrasound for processing effects such as emulsification, extraction, homogenization, and assisted freezing and drying; and low-power ultrasound for non-invasive sensing of texture, composition, and fill levels. Power ultrasound’s cavitation disrupts cells and microbes, while diagnostic beams image internal structure harmlessly — frequency, amplitude, and exposure time deciding whether the outcome is analytical or transformative.