Response surfaces of total oil yield of turmeric (Curcuma longa) in supercritical carbon dioxide

The process variables pressure, temperature and flow rate were studied for optimisation of total oil yield by response surface methodology following a Box-Behnken design of experiments. The results indicated: (a) a rise in th e temperature of extraction leads to decrease in oil yield. (b) The optimum pressure for the extraction of oil was found to be 22.5 MPa. (c) general i ncrease in oil yield with an increase in flow rate. The experimental oil yi eld is in good agreement with the predicted one. The response surface metho dology used in this study was able to predict the optimal extraction condit ions for the total yield of turmeric oil. (C) 2000 Elsevier Science Ltd. Al l rights reserved.