Abstract: Onion (Allium cepa L) is an important flavoring that commands universal application as seasonings with vegetables in East daily diet. The onion can be used to kill a variety of bacteria, fight against arteriosclerosis, hypertensive, hyperlipemia and coronary heart disease. Sulfur compounds is the main component in onion oil, the spicy ingredient in fresh onion, the major active ingredient in onion; Onion will be a health products that has great value of development and application after the process of appropriate embedding.
The experiment on extraction of onion oil with supercritical carbon dioxide was carried out. The influences of operating pressure, operating temperature, operating time, entrainer and other important parameters on the yields of onion oil were studied. Through experiments, the best parameter of extraction of onion oil with SC-CO2 extraction technology was ascertained. The optimal parameters were that extracting pressure, 20MPa; extracting temperature, 40℃; extracting time, 240min; 15% anhydrous ethanol. Meanwhile, the pilot scale experiment at this condition was carried out, the yield of onion oil could be 0.489%. The result was same as the ones of bench scale.
Key Words: Supercritical; Dioxide carbon; Extraction; Onion oil; Pilot scale
