term (x1), three quadratic terms (x1
2 and x3 2 ) and three interaction
terms (x1 x2, x1x3 and x2 x3)were all significant (P < 0.05), while the
other terms were insignificant (P > 0.05). The lower the value of the
coefficient of variation, the higher the reliability of the experiment.
Those significant terms played a dominant role in rice lipid
extraction by ultrasound. Based on the significant terms, the
regression equation for the UAE efficiency was obtained as follows