Abstract: The ultrasonic extraction conditions for crude polysaccharide from pear adzuki beans were optimized with response surface method in this study.Influences of factors such as ultrasonic power,solid to liquid ratio,ultrasonic temperature and ultrasonic time on the extraction yield of crude polysaccharide from pear adzuki beans was optimized with single factor experiment and response surface analysis.The optimized conditions for pear adzuki beans crude polysaccharide extraction were:ultrasonic power of 254 W,solid to liquid of 25.5:1 mL/g,ultrasonic time of 26.2 min and ultrasonic temperature of 78.4 ℃.The experimental yield of pear adzuki beans crude polysaccharide was 0.34±0.015%.The deviation between the predicted and experimental extraction yield of pear adzuki beans crude polysaccharide was very small.

Key words: Pear adzuki beans, crude polysaccharide, response surface methodology, ultrasonic extraction