Abstract: The quadratic orthogonal rotation design with five factors was used to study the effect of the acid concentration,temperature,time,material fluid ratio,and extracting times by acid extraction from peanut meal in the research.The regression equation to five factors were established by RSREG software in SAS8.1.Results showed that the regression equation is significant,and the mathematical model for the simulation is presented.Through partial in research of optimization analysis to the regression equation,it was found that the optimum technical conditions were as follows:peanut meal was marinated with 25 times of 0.68 mol/L HCl at 87 ℃ for 74 min,extracting one time.The yield of soluble polysaccharides by acid extraction from peanut meal is 9.41% under these conditions and verified value is 9.39%.

Key words: peanut meal polysaccharides, acid extraction, orthogonal rotation design