ABSTRACT
Ultrasonics, a non-thermal processing technique, is one of the fast, versatile, and promising non-destructive green technologies used in the food industry in various areas of food processing, i.e., blanching, freezing, degassing, extraction, drying, filtration, emulsification, sterilization, cutting, and other applications. The application of ultrasonic waves in food processing includes extraction and separation, sterilization and fresh-keeping, detection and analysis in food, freezing, thawing, crystallization, filtration, drying, and osmotic dehydration. The ultrasonic transducers convert electrical or mechanical energy to sound energy. There are three types of ultrasonic transducers in common usage: liquid-driven transducers, magnetostrictive transducers, and piezoelectric transducers, with piezoelectric being the most common. The systems that are particularly suitable for large-scale usage in the food industry are resonating tube reactors. The liquid to be processed is passed through a pipe with ultrasonically vibrating walls. Ultrasonication has a potential to overcome harmful effects of thermal processing with retention of phytonutrients and, therefore, offers a better alternative in various food processing applications.
