Quantitation of volatile oils in ground cumin by supercritical fluid extraction and gas chromatography with flame ionization detection

Ground cumin is used as a flavoring agent in a number of ethnic cuisines. T he chemical entities, which primarily establish its characteristically pung ent flavor, are found in the volatile oil of cumin. Fixed oils and carbohyd rates tend to round out the harshness of the volatile oil components. Howev er, the quantity of volatile oil is commonly the measure of the quality of this spice. For several decades, the spice industry has used a classical di stillation procedure for the determination of volatile oil in cumin and oth er spices. However, the method is cumbersome and requires nearly 8 h to com plete. Supercritical fluid extraction with capillary gas chromatography-fla me ionization detection is utilized in the formulation of a rapid, accurate , and specific method for the determination of volatile oil in ground cumin . Samples are extracted in a static-dynamic mode with CO2 at 550 bar and 10 0 degreesC. Toluene is used as a static modifier addition. The extracted vo latile oil, collected in toluene, is analyzed directly using tetradecane as the internal standard. Integration is performed as grouped peaks to includ e all chemical entities found in cumin volatile oil recovered from the offi cial distillation procedure. Results from this procedure compare favorably with those obtained by the official procedure (coefficient of correlation = 0.995, 24 samples).