微波辅助萃取法快速测定苎麻果胶含量的研究

采用微波辅助萃取法测定苎麻中的果胶含量,研究了苎麻粒径、液料比、微波功率、微波辐照时间、萃取次数等因素对微波辅助萃取果胶的影响。结果表明:苎麻浸泡20 min后,在微波功率450 W、苎麻粒径1.0 cm、液料比为1∶20(g/ml)条件下进行微波辅助萃取,辐照时间每次6 min,连续萃取2次后可达到GB5889-86中苎麻果胶的测定效果。试验将萃取时间从国标法的3 h缩短到12 min,测定的相对标准偏差为2.23%,并采用咔唑比色法对微波辅助萃取液中所含果胶进行了分析。

Study on the Rapid Determination of Pectin Content in Ramie by Microwave-assisted Extraction

The content of pectin in ramie was determined by microwaveassisted extraction.And the influences of such factors as ramie diameter,the material-to-solvent ratio,microwave power,microwave irradiation time and extraction times on the extraction effect were studied.The results showed that microwave-assisted extraction was made on ramie under the conditions as the microwave power of 450 W,ramie diameter of 1.0 cm and the liquid-material ratio of 20 ml/g after ramie was soaked for 20 min.After extracting twice continuously with every irradiation time for 6 min,the determination effects of ramie pectin could achieved the standard of GB5889-86.In the test,the extraction time was shortened from 3 h to 12 min,with the relative standard deviation of 2.23%.The content of pectin in microwave-assisted extract liquid was analyzed by using carbazole colorimetry.