Abstract: The extraction technics of β-carotin with ultrasonic auxiliary in sweet potatoes were studied in this paper. The results showed that the procedures are optimal to extract β-carotin with ultrasonic auxiliary: at room temperature, using acetone- petroleum ether(3:7) as solvents, and then extracted 25min for 3 times with the proportion of material and solvent(1:4). The extraction method of β-carotin with ultrasonic auxiliary is superior to that of general saturation. The process with ultrasonic auxiliary costs less solvent and time. It proves to be a feasible way to extractβ-carotin.

Key words: sweet potato； ultrasonic extraction method； &beta, -carotin；