Optimization of Technical Parameters of Ultrasound-assisted Extraction of the Black Glutinous Corncob Pigment

The technological conditions for ultrasonic-assisted extraction of pigment from black glutinous corncob were studied. The effect to the extraction yield of extraction reagent, extraction temperature, ultrasonic power and the ratio of solid to solvent were studied . Orthogonal experiments were carried out to determine important or minor factors, and the optimum technological parameters on the effects of ultrasonic-assisted method. Additionally, the ultrasonic-assisted was compared with the traditional method on extraction of pigment. The results showed that the effectiveness of factors on extraction of pigment was in this order: extraction temperature ratio of solid to solvent ultrasonic power extraction time. And the optimum technological parameters as follows: extraction temperature was 65℃, ratio of solid to solvent was 1:8, ultrasonic power was 144W respectively and extraction time was 45min, extraction times were two. Using ultrasonic method, the extraction yield reached 18.66%. The extraction yield was 0.71% more than the traditional solvent extraction, and the difference was significant, the traditional solvent extraction time was 32 time higher than ultrasonic-assisted extraction time. Technology of ultrasonic-assisted of pigment from the black glutinous corncob had the advantages of short time, high efficiency and high yield.