Application of high-power ultrasound for drying vegetables

7 pages.-- PACS nr.: 43.35Ty.-- Communication presented at: Forum Acusticum Sevilla 2002 (Sevilla, Spain, 16-20 Sep 2002), comprising: 3rd European Congress on Acoustics; XXXIII Spanish Congress on Acoustics (TecniAcústica 2002); European and Japanese Symposium on Acoustics; 3rd Iberian Congress on Acoustics.-- Special issue of the journal Revista de Acústica, Vol. XXXIII, year 2002.High power ultrasound represents a means for food dehydration without affecting the main characteristics and quality of the product. The application of ultrasonic energy can be made alone or in combination with other kind of energies such as hot-air. In this latter case ultrasound helps in reducing temperature or treatment time.This paper deals with an experimental work in which the results obtained with different kind of vegetables (apple, carrots, mushroom, etc.) under the application of ultrasonic vibration at 20 kHz are presented. Several experimental techniques such us direct contact of the ultrasonic vibration with the product, standing wave and near-field conditions were tested, together with hot-air at several temperatures.This work was developed in the frame of by the Research Project AGL2001-2774-CO5-02.Peer reviewe