Extracting Technology of Red Pigment from Purple Sweet Potato

Purple sweet potatoes were used as raw material,and the effects of extracting red pigment from purple sweet potato by solvent,ultrasonic wave and microwave were studied.The results indicated that the extracting rate of solvent extraction was high,but the time was long;the extracting rate of ultrasonic wave extraction was low;microwave extraction was a good method.With the parameters of 1.0% citric acid,material/solvent ratio1:40,microwave power 700W,extracting time 45s,for three times,the extracting rate reached 9.469mg·g-1.