Comparison Between Coriander Volatile Oils Obtained by Supercritical CO_2 Extraction and Hydrodistillation

摘要

Supercritical fluid extraction (SFE) with CO_2 of volatile oil from coriander (Coriandrum sativum L.) seeds was carried out at the temperature of 40°C and pressures up to 150 bar with a flow apparatus using a two stage fractional separation technique. Two ecotypes growing in different environmental conditions, one from Spain and the other from Italy, were studied. The best conditions of extraction (90 bar and temperature of 40°C), and separation (pressure of 70bar and temperature of -8°C, in the first separator, and a pressure of 20 bar and a temperature of -5°C, in the second one), were used to assess the effect of different mean particle size. The yield of the extraction and composition of the volatile oil were compared with those obtained by hydrodistillation. The study showed that the particle size of seeds influence the yield and the composition of the oil in SFE. The coriander oil was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The main compounds identified in the oils were α-pinene (2.5%), myrcene (1.7%), linalool (74%), camphor (3.3%), geraniol (3%) and geranylacetate (1.3%)