分光光度法测定油条中铝残留量的不确定度评定

Evaluation of Uncertainty in the Determination of Aluminum Residue in Deep-Fried Dough Sticks by Spectrophotometry

采用分光光度法测定油条中铝的残留量,通过分析影响测量结果的不确定度来源,评定各个不确定度分量,计算合成与扩展不确定度,结果表明,油条样品中铝残留量为60.13 mg·kg^(-1)时,扩展不确定度为3.69 mg·kg^(-1)(k=2),铝校准曲线拟合、铝标准工作溶液配制与测量重复性引入的不确定度对测量结果影响较大。

The residual amount of aluminum in deep-fried dough sticks was determined by spectrophotometry.The sources of uncertainty affecting the measurement results were analyzed,the components of uncertainty were evaluated,and the synthesis and extended uncertainty were calculated.The results showed that when the residual amount of aluminum in deep-fried dough sticks sample was 60.13 mg·kg^(-1),the extended uncertainty was 3.69 mg·kg^(-1)(k=2).The uncertainty introduced by aluminum calibration curve fitting,aluminum standard working solution preparation and measurement repeatability has great influence on measurement results.