Abstract: Before germinating under 35 ℃ for 24 hours,brown rice was treated with ultrasonic at 28 kHz and 40 kHz for 0,2,4,8,16 and 32 minutes,respectively.The effects of ultrasonic treatment were studied on the main components and relative enzyme activity of germminated brown rice.Results showed that the contents of soluble protein,gamma-aminobutyric acid and free amino acid increase after ultrasonic treatment at two frequencies,and are highest at 8 and 16 minutes respectively.With treatment time extending,the content of starch decreases and reduced sugar increases at 28 kHz,but α-amylase activity is improved obviously by the ultrasonic treatment at 40 kHz.

Key words: ultrasonic； germminated brown rice； starch； reduced sugar； free amino acid； gamma-aminobutyric acid； &alpha, -amylase activity；