摘要
传统的络合滴定法测定羧甲基淀粉取代度(DS)时,存在耗时长,稳定性差,高取代度羧甲基淀粉测定效果差等问题。本文采用将过量CuSO4溶液加入pH6.0～7.0的变性淀粉溶液中,生成羧甲基淀粉铜沉淀,过滤除去沉淀,再调节pH至7.5～8.0后,采用1-2-吡啶偶氮-2-萘酚(PAN)为指示剂,用EDTA标准溶液滴定过量的Cu2+的方法来测定羧甲基淀粉的DS。该法简便快速,准确可靠,稳定性好,可适用于羧甲基淀粉工业简便快速的检测。
Long time,poor stability,and especially big error were the main limitation of traditional complexometric determination of hig h deg ree of substitution(DS)of carboxymethyl srarch.In this paper,an improved method for determination of DS was provided,its main process including :adding excessive CuSO 4 into carboxymethyl starch solution,adjusting pH to6.0～7.0,removing precipitation throug h filtration,and adjusting pH to7.5～8.0ag ain,then using PAN to titrate excessive Cu 2+ with EDTA standard solution.This method featured with g ood accuracy and preciseness,simpleness,rapidness and stability,and is suitable for routine measurement.
出处
《食品工业科技》
CAS
CSCD
北大核心
2003年第3期82-84,共3页
Science and Technology of Food Industry
基金
安徽省"十五"农产品加工重大科技专项项目(项目编号Z081003)
