浅谈食用碱重金属铅的检测方法的改进

Experimental Methods Improvement of Heavy Mental Lead in Edible Alkali

根据国家食品安全法要求,食用碱必须要做重金属铅的限量试验,可是依照国标的分析方法,在操作过程中存在一些问题,铅的分析中最主要的就是调p H值,因为铅只有在p H值为3~4时,才会显色,试样中加入国标规定的试剂的量即可达到要求,可是标准比对溶液中加入规定的量并不能达到要求的p H值,而且为了达到要求的p H值要加入比试样多的试剂,溶液的体积很难控制到50 m L以内,所以,要找出解决这些问题的方法是非常必要的。

According to the requirement of National Food Security Act,lead limit test must be done in the food alkali base. However,in accordance with the national standard analysis method,there are some problems in the operation process. The p H adjustment is the most important to analysis of lead because lead can show the color only at p H 3 ~ 4. The amount of reagent added to the sample according to the national standard can reach the requirements,but a predetermined amount added to the standard intercomparison solution can not achieve the required p H. And in order to achieve the required p H to add more than sample reagent,it is difficult to control the volume of the solution to less than 50 m L. So it is very necessary to find solutions to these problems.