OBJECTIVETo determine the best processing technology parameters.

METHODThe changes of the weights, volatile constituents, total extract quantities by MeOH or CHCl3 and curcumenol contents of the roots of Curcuma wenyujin and C. kwangsiensis roots before and after water soaking were determined, so as to determine the quality control index for the process of preparing Yujin slices. The shortest soaking and moistening time and the appropriate drying temperature were studied.

RESULT AND CONCLUSION(1) The weight was decreased and the quantities of volatile constituents were changed during water soaking process. But the total extracts quantities and the curcumenol contents didn't change obviously. So the quality control index was decided as soaking as short as possible. (2) The soaking time could be decreased by using high pressure. The soaking time was related with the short diameter of the cross section of the root. (3) The soaking under pressure technology is that soaking on -0.095 MPa for 0.5 h, then on 0.14 MPa for 10-16 h, and moistening for 36-48 h, cutting drying in room temperature or less than 40 degrees C.