The perservative in liquid beverage was extrcated with n-hexane.The hexane layer was subjected to cyclodextrine polymer resin colume.The colume was eluted with aqueous solution of ethanol.

用正己烷萃取液体饮料中的防腐剂，使萃取液经环糊精交联树脂分离后，用乙醇溶液洗脱。