The influence of the drying method on volatile Compounds of Origanum vulgare was evaluated. The drying methods tested were convective (CD) at 60 degrees C and vacuum-microwave (VIVID), as well as a combination of convective pre-drying and VM finish-drying (CPD-VMFD). The volatile compounds of fresh and dried oregano were extracted by steam-hydrodistillation and analyzed by GC-MS. Oregano drying kinetics was described by a simple exponential model for CD and CPD-VMFD, while VIVID kinetics consisted of two periods: linear until a critical point and exponential beyond that point. Thirty-four Compounds were tentatively identified, with carvacrol, thymol, and gamma-terpinene. being the major components. The total volatiles concentration of fresh oregano (33.0 g kg(-1)) decreased significantly during drying, independently of the method used (CD: 10.2 g kg(-1), CPD-VMFD: 13.1 g kg(-1), and VMD: 27.9 g kg(-1)). The final conclusion was that VM dehydrated Polish oregano was of better aromatic quality than that dried using hot air. (C) 2010 Elsevier Ltd. All rights reserved.