Optimization of Subcritical 1,1,1,2-Tetrafluoroethane( R134a ) Removal of Cholesterol from Spray-Dried Sthenoteuthis oualaniensis Egg Powder Using Response Surface Methodology

Abstract

Subcritical 1, 1, 1, 2-tetrafluoroethane (R134a) extraction was applied to remove cholesterol from spray-dried Sthenoteuthis oualaniensis egg powder. Response surface methodology (RSM) was applied to optimize the parameters of subcritical R134a extraction (pressure, temperature, and extraction time) on removal rate of cholesterol. Response surface analysis showed that the data came to a precise fitting to a second-order polynomial model. The quadratic terms of pressure and temperature had high significant negative effects (p＜0.001) on removal rate. The optimum parameters of the variables were 8.6 MPa, 55.4 °C, 50 min. Under these conditions, removal rate of cholesterol was predicted to be 101% and experiments gave out the removal rate of 99.16%, which concurred with the model prediction. Furthermore, the removal efficiency of cholesterol by R134a was higher than those achieved by using supercritical carbon dioxide(SC-CO2)and β-cyclodextrin extraction methods.