影响食盐中碘含量检测结果准确性的主要因素

The Main Factors that Effects the Accuracy of Iodine Content Test Results of Edible Salt

碘是食盐重要的监测指标,研究了影响食盐中碘含量检测结果准确性的主要因素及试验过程中注意的事项。结果表明,对于加碘食盐而言,为保证检验结果的准确性,检测过程中应注意:①将碘盐研磨粉碎后均匀取样;②有效氯含量应适度过量,含量为3%较为适宜;③滴定过程中试样溶液滴定至浅黄色后再加入淀粉指示剂;④滴定终点以样液蓝色消失为终点,切勿直接滴定到澄清透明。

Iodine is an important monitoring index of edible salt.This paper analysed the main factors that effects the accuracy of iodine content test results of edible salt and pointed out the matters worthy of note in that experiment.The results were as follows:for iodized salt in order to ensure the accuracy of the test results during the experiment,attention should be paid to①The salt should be taken evenly after grinding;②Active chlorine content should be moderately excessive,the content of 3%is more appropriate;③The sample solution was titrated to light yellow,then starch indicator was added;④The endpoint of titration was the disappearance of blue of sample solution,don't titrate to clear and transparent.