Supercritical carbon dioxide extraction of volatiles from spices: Comparison with simultaneous distillation–extraction

Supercritical fluid extraction (SFE) and simultaneous distillation–extraction (SDE) were used to extract the essential oils from three different spices (oregano, basil, and mint), and a comparative study of extracts obtained using SFE and SDE is presented. Temperature and pressure for the SFE extraction were optimized prior to the experimental extractions. The extracts obtained using the two methods were very similar in composition, but SFE yielded better relative standard deviations and avoided the thermal degradation or solvent contamination of samples.