Extraction of volatile oil from cumin (Cuminum cyminum L.) with superheated water

A comparative study of superheated water extraction (SWE) with two conventional methods including hydrodistillation and Soxhlet extraction was performed on cumin (Cuminum cyminum L.). The effect of some superheated water parameters at 20 bar pressure on the essential oil extraction from 4 g cumin seeds such as temperatures from 100 to 175C, particle size at 0.25 and 0.50 mm, and flow rates at 2 and 4 mL/min were investigated. Separation and identification of the components were carried out by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. The best operating conditions for the SWE of C. cyminum L. were determined to be 150C temperature, 0.50 mm mean particle size and 4 mL/min flow rate for 3-h extraction time. The SWE method resulted in a more valuable essential oil with respect to the oxygenated components.