Multi-stage decoloring method for pectin

The invention discloses a multi-stage decoloring method for pectin. The method comprises the following steps of: dissolving citrus powder in water, adjusting the pH value to 1-3, carrying out a reaction for 1-2 h under magnetic stirring at 70-90 DEG C, filtering the reaction liquid, centrifuging the filtrate, and collecting the supernatant; adding a decolorizing agent into the supernatant, standing and decolorizing at 30-60 DEG C for 25-35 minutes, centrifuging, and collecting the supernatant; and adding ethanol into the supernate, standing and precipitating at room temperature for 1-3 hours, filtering, washing a filter cake with ethanol, filtering, and drying the filter cake to obtain decolorized pectin. The yield of the multi-stage decolored pectin prepared by the method is 8.9-26.8%, the color value A420 of the pectin is less than 1.381, the esterification degree of the pectin is 67.5-84.9%, the apparent viscosity of the decolored pectin measured by a rotational rheometer is 0.3569-21.777 mPa.s, and the ge