Mechanistic and synergistic aspects of ultrasonics and hydrodynamic cavitation for food processing

Compared with traditional methods, cavitation-based processing technology has received extensive attention for its low energy consumption and high processing efficiency. The cavitation phenomenon releases high energy due to the generation and collapse of bubbles, which improves the efficiency of various food processing. This review details the cavitation mechanism of ultrasonic cavitation (UC) and hydrodynamic cavitation (HC), factors affecting cavitation, the application of cavitation technology in food processing, and the application of cavitation technology in the extraction of various natural ingredients. The safety and nutrition of food processed by cavitation technology and future research directions are also discussed. The mechanism of UC refers to longitudinal displacement of the particles of the medium induced by ultrasonic waves causing a series of alternating compression and rarefaction of particles, whereas HC occurs when liquid enters a narrow section and undergoes large pressure differentials, both of which can trigger the generation, growth, and collapse of microbubbles. Cavitation could be applied in microbial inactivation, and drying and freezing processing. In addition, cavitation bubbles can have mechanical and thermal effects on plant cells. In general, cavitation technology is a new sustainable, green, and innovative technology with broad application prospects and capabilities.