Improvement on Preteatment for Determining Pectin in Tobacco with Enzymolysis-flowanalysis

The sample pretreatment in determining pectin in tobacco by enzymolysis-flowanalysis method was improved in order to accelerate the analytical process.The sample was directly extracted with 5% acetic acid instead of 80% ethanol reflux extraction to remove soluble sugar from tobacco,then analyzed by enzymolysis-flowanalysis.The pectin contents in 20 flue-cured tobacco leaf samples extracted with 5% acetic acid and 80% ethanol respectively were determined.The results indicated that the average recovery of pectin by acetic acid extraction was from 99.5% to 105.7% with the CV of 2.08%.The pectin content determined with acetic acid treatment was slightly higher than that with 80% ethanol,however,the difference was not significant.