Supercritical carbon dioxide extraction of Algerian fenugreek seed oil (Trigonella foenum-gracecum L.). experimental study and optimization of oil yield

Oil from local fenugreek (Trigonelle foenum-gracecum L.) seeds was extracted by means of supercritical carbon dioxide. The process was optimized in the temperature, pressure and particle size ranges of 308.15-328.15 K, 100-400 bar and 0.5-1mm, respectively, by means of the response surface methodology (RSM) based on Box-Behnken design. The obtained optimum extraction yield was equal to 5.464% at a pressure of 400 bar, a temperature of 327.25 K and a particle size of 0.5mm, and was close enough to the experimental yield of 5.069%. GC-MS analyses showed that the major compounds were Oleic, Linoleic acids and aromatics, at the optimal conditions.