The present work is focused on the optimization of the internal wool lipid (IWL) extractive process at laboratory level using supercritical carbon dioxide (SCCO2) as solvent. IWLs have been extracted from wool on account of their considerable dermatological interest owing to their proportion of ceramides. Selected extraction variables affecting supercritical fluid extraction (SFE) are optimized to obtain natural lipid extracts rich in ceramides. The type of modifierwas first evaluated and the best results were obtained using SCCO2 in the presence of methanol and ethanol. Subsequently, pressure, temperature and CO2 volume were optimized by using experimental design approaches. The result highlights the small influence of the temperature in both cases. 60 degrees C can be considered as a good temperature to obtain high amount of ceramides, around 0.25% on wool weight with 10% methanol and 0.20% on wool weight with 10% ethanol in the SFE procedure, being in both cases important is the pressure and CO2 volume used. (c) 2008 Elsevier B.V. All rights reserved.