The invention discloses a method for preparing sulfated apple 
pomace polysaccharide through twin-screw 
extrusion, and belongs to the technical field of 
food processing. The method comprises the following steps: (1) carrying out 
extrusion modification on apple 
pomace subjected to 
moisture adjustment by adopting a double-screw extruder, and performing 
drying, crushing and sieving to obtain modifiedapple 
pomace; (2) adding 
distilled water into the modified apple pomace, performing leaching in a water bath, removing filter residues, concentrating under reduced pressure, carrying out 
alcohol precipitation, standing, centrifuging, removing supernatant, and 
drying the precipitate to obtain apple pomace 
polysaccharide; and (3) dispersing the apple pomace 
polysaccharide in 
dimethylformamide, adding 
sulfamic acid under a stirring condition, uniformly mixing, carrying out 
esterification reaction under an ultrasonic condition, cooling to 
room temperature, regulating the pH value until the solution is neutral, carrying out 
alcohol precipitation, dissolving the obtained precipitate in 
distilled water, performing dialyzing, and 
drying the obtained product to obtain the sulfated apple pomace polysaccharide. The method has the advantages of high production efficiency, high yield, safety and no 
toxicity of the product, and high yield of the obtained product.