微波消解-分光光度法测定面食中的铝含量

Determination of Aluminum Content in Pasta with Microwave Digestion and Spectrophotometry

用微波消解-分光光度法测定面食中的铝含量。用微波消解对面食进行了预处理,采用分光光度法测定其中的铝含量。经过实验测定的最优条件为:λmax=615nm,抗坏血酸的用量为1.00mL,铬天青S的用量为2.50mL,显色时间为30min,pH=6.7~7.0,铝在0~0.2μg/mL范围内线性良好,线性回归方程为Y=0.0895X-0.0148,相关系数R2为0.9916,相对标准偏差为1.00%,加标回收率为89.95%~114.75%。实验测得太阳饼中铝含量为676.3083μg/mg,超出国家食品安全标准的6~7倍。手撕面包中的铝含量为83.2417μg/mg,馒头中的铝含量为29.1976μg/mg,这两种面食中铝元素的含量均符合国家卫生标准。与国标法中湿法消解法相比,微波消解-分光光度法测定酸液试剂用量更少,耗时更短,过程更环保。因此微波消解-分光光度法测定面食中的铝含量是一种更加高效的方法。

To establish a method for determination of aluminum in pasta with microwave digestion spectrophoto⁃metric.The pasta was pretreated by microwave digestion and the aluminum content was determined by spectropho⁃tometry.The optimal conditions determined by the test:λmax=615nm,the amount of ascorbic acid was 1.00mL,the amount of chromium-azurite S was 2.50mL,the chromogenic time was 30min and the pH was 6.7~7.0,the linear re⁃gression equation was Y=0.0895X-0.0148,the correlation coefficient R2 was 0.9916,the relative standard deviation was 1.06%,and the standard recovery was 89.95%-114.75%.The aluminum content of the sun cake was 676.3083μg/mg,which was 6~7 times higher than the national food safety standard.The aluminum content of the bread was 83.2417μg/mg,and that of the steamed bread was 29.1976μg/mg.Compared with the wet digestion meth⁃od in the national standard method,the acid reagent dosage microwave digestion-spectrophotonetry is less,the time is shorter,and the process is more environmentally friendly.Therefore,microwave digestion-spectrophotometry is a more efficient method to determine the content of aluminum in pasta.