Consumers' demand and quality requirements for dehydrated foods are gradually increasing，and the market of high-end dehydrated foods is expanding day by day. High-quality and efficient drying technology is an effective means to solve the technical bottleneck of high-end dehydrated foods. This article expounded the application of the ultrasonic treatment in food drying process，compared it with single drying methods，and analyzed the advantages of ultrasonic application in food drying process. Ultrasonic treatment could help the formation of cavitation bubbles and accelerate the removal of water closely integrated with the material. It could also promote the formation of micro-pores in the material, thereby reducing the thickness of the heat transfer surface and increasing the speed of mass transfer. Therefore, with the ultrosonic technology, the drying rate could be increased and nutrients could be better retained. There are currently many researches on the auxiliary effect of single frequency ultrasound，and the study of multi-frequency ultrasound will become a more important part in the study of ultrasound enhanced fruit and vegetable drying.
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