Breaking the cells of rape bee pollen and consecutive extraction of functional oil with supercritical carbon dioxide

Supercritical carbon dioxide was applied to break the cell wall of rape bee pollen and consecutively extract lyzed bee pollen oil. The supercritical CO2 rapid depressurization was carried out on the bee pollen. The conditions of consecutive extraction of lyzed bee pollen oil were optimized using response surface methodology and performed at the range of pressure 13.2-46.8 MPa. temperature 33.2-66.8 degrees C and CO2 flow rate 6.6-23.4 L/h. Scanning electron microscopy studies revealed that supercritical CO2 treatment was an effective way to break cell of rape bee pollen and higher CO2 pressure was found to be more effective. The extraction pressure, temperature and CO2 flow rate significantly affected the yield of lyzed bee pollen oil in supercritical CO2 extraction. Optimum oil yield was obtained as 5.98 g/100 g dry pollen at the following predicted conditions: extracted at 39.2 MPa and 54.7 degrees C with CO2 flow rate of 17.1 L/h after bee pollen was treated with supercritical CO2 at 45 MPa for 10 min and then depressurizing. Polyunsaturated fatty acids were the predominant fatty acids in the extracted oil, indicating its potential in the nutraceutical industry. Industrial relevance: The application of supercritical CO2 technology in food industry has received much attention in recent years. This study investigates the feasibility of breaking pollen cell wall by supercritical CO2. The procedure is under low temperature with short time. From an industrial point of view, it is a promising method for breaking bee pollen cell wall. The optimum parameter of supercritical CO2 extraction of functional pollen oil simultaneously obtained from the process may also be attractive to the food and nutraceutical industries. (C) 2008 Elsevier Ltd. All rights reserved.