Abstract:To establish a new decolorization evaluation method，this paper used the area under the curve（AUC）of the sample absorbance curve as the basis for decolorization rate calculating and applied the AUC to the decolorization process investigation of Lycium barbarum polysaccharide，thus exploring the optimal decolorization process of L. barbarum polysaccharide. The paper performed full wavelength scanning on solutions of three pigments（proanthocyanidins，sodium copper chlorophyll，and beta-carotene）at 200-760 nm through ultraviolet-visible spectrophotometry and calculated the AUC of the sample solutions before and after decolorization through Origin，thus calculating the decolorization rate. The method of AUC decolorization was introduced into the decolorization process investigation of L.barbarum polysaccharide to select the decolorization effects of different types of macroporous resins and determined the optimal decolorization conditions through single factor and orthogonal tests. The results showed that the three pigments had good linear relationships in the ranges of 0.98-31.25，3.92-125.00，and 0.39-12.50 μg/mL respectively，with R2≥0.998 6. The average recovery rates were 101.86%，100.08%，and 100.68% respectively，and the relative standard deviation（RSD）were 2.66%，2.27%，and 2.55% respectively. With the AUC decolorization rate calculating method，the crude L. barbarum polysaccharide was decolorized through S8 macroporous resin. The optimal decolorization process was 7.5 g of S8 resin per 100 mg of crude polysaccharide，with a crude concentration of 3 g/L and a decolorization time of 60 min. Under the optimal decolorization process，the average decolorization rate was 73.01%，and the RSD was 1.01%，indicating good stability.