婴幼儿配方乳粉中磷含量的测定

Determination of Phosphorus Content in Formula Milk Powder for Infants and Young Children

为准确测定婴幼儿配方乳粉中的磷含量,对测定方法的最佳实验条件、精密度、稳定性、重现性及回收率进行研究。结果发现采用可见分光光度法测定婴幼儿配方乳粉中的磷含量,重现性好,准确度高,建立的线性方程为y=0.0372x+0.0039(R2=0.9997),方法的平均回收率为98.5%、RSD值为0.39%。随机抽取市售的30批次婴幼儿配方乳粉进行检测,发现不同阶段的乳粉磷含量不同,含量顺序为幼儿配方乳粉>较大婴儿配方乳粉>婴儿配方乳粉,具体值分别为(448±56)、(382±59)、(250±58)mg/g,不同品牌同一阶段的乳粉磷含量也存在较大差异。

A spectrophotometric method for the determination of phosphorus content in formula milk powder forinfants and young children was developed. Under optimized experimental condiitons, the proposed method was highly reproducible and accurate. The following standard curve was established： y = 0.0372x ＋ 0.0039 （R2 = 0.9997）. The average recovery of this method was 98.5% with a RSD of 0.39%. Milk powder samples randomly selected from 30 commercial batches showed different levels of phosphorus, depending on age group. Three age groups decreasing order of phosphorus content were： yotmg child＇ formula milk powder, older infant＇s milk powder and young infant＇s milk powder, which were （448±56）, （382±59） mg/g and （250±58） mg/g, respectively. Morevoer, samples from different manufactures and the same age group also revealed greatly varying levels of phosphorus.