Ultrasonic-Assisted Extraction and Characterization of Ginseng Starch

The ultrasonic-assisted extraction of ginseng starch was optimized using single-factor and orthogonal array designs. The extraction yield of ginseng starch was investigated with respect to ultrasonic power, ultrasonication time, ratio of material to liquid and material particle size. The particle and physicochemical properties of ginseng starch were studied by using scanning electron microscope, polarizing microscope, infrared spectrometer, Brabender viscograph and texture analyzer. The results showed that the optimal conditions for ultrasonic-assisted extraction of ginseng starch were found to be ultrasonic power 600 W, ultrasonic time 20 min, ratio of material to liquid 1:25(g/mL) and material particle size 80 mesh. The extraction yield of ginseng starch under the optimized conditions was up to 70.51%, which was 10.69% higher than that obtained with the conventional method. Ginseng starch from the ultrasonic-assisted extraction exhibited increased levels of amylose content, solubility, swelling power and transparency and reduced retrogradation property, and had a gelatinization temperature of 70.5 ℃ and a peak viscosity of 70.0 BU.