Applications of ultrasound in food industry

U is well known to have a significant effect on the rate of various processes in the food industry. Using ultrasound, full reproducible food processes can now be completed in seconds or minutes with high reproducibility, reducing the processing cost, simplifying manipulation and work-up, giving higher purity of the final product, eliminating post-treatment of waste water and consuming only a fraction of the time and energy normally needed for conventional processes. The advantages of using ultrasound for food processing includes: more effective mixing and micro-mixing, faster energy and mass transfer, reduced thermal and concentration gradients, reduced temperature, selective extraction, reduced equipment size, faster response to process extraction control, faster start-up, increased production, and elimination of process steps. Food processes performed under the action of ultrasound are believed to be affected in part by cavitation phenomena and mass transfer enhancement. Ultrasonic is a rapidly growing field of research, which is finding increasing use in the food industry for both the analysis and modification of food products. The sound ranges employed can be divided into high frequency, low energy diagnostic ultrasound and low frequency, high energy power ultrasound. The former is usually used as a non-destructive analytical technique for quality assurance and process control with particular reference to physicochemical properties such as composition, structure and physical state of foods. Nowadays, power ultrasound is considered to be an emerging and promising technology for industrial food processing. The use of ultrasound in food processing creates novel and interesting methodologies which are often complementary to classical techniques. Various areas have been identified with great potential for future development: bleaching, crystallization, drying, degassing, filtration, extraction, freezing, homogenization, meat tenderization, sterilization, tempering, etc. There is a wide scope for further research into the use of ultrasound in food processing both from an academic and industrial viewpoint.