Applications and Advances of Ultrasound in Food Processing

Ultrasound is a sound wave that can propagate parallel or perpendicular to the direction of travel through a material. Ultrasound treatment involves transmitting energy at frequencies above 20 kHz. Currently, ultrasound is utilized in food processing for various applications beyond preservation, including degassing, foam control, mixing, emulsification, homogenization, extraction and meat tenderization. At high intensities, ultrasound exhibits antimicrobial properties, making it a potential method for food preservation. However, one of its limitations is that the intensity required for microbial inactivation can also cause physical changes in food. Ultrasound induces cavitation, and localized heating may lead to the formation of free radicals. Nevertheless, low-intensity ultrasound shows promise when integrated into combination preservation strategies. Additionally, high-intensity ultrasound, when combined with other preservation technologies, is effective in inactivating heat-resistant microbial spores. Despite its potential, ultrasound has not yet been widely adopted for monitoring food processing operations due to scalability issues.