食品中铝含量检测优化技术体系研究

目的建立高效的测定食品中总铝和可溶性铝的测定方法。方法采用微波消解法(HNO_3、HNO_3+H_2SO_4、HNO_3+HF)与湿法消解法(HNO_3、HNO_3+H_2SO_4)进行样品前处理,在铬天青S分光光度法和电感耦合等离子体发射光谱法(inductively coupled plasma optical emission spectrometry,ICP-OES)下测定标准参考物质与普通样品铝含量,同时用添加回收实验验证方法的可靠性与准确性。结果采用微波消解法(HNO_3+HF)-优化铬天青S分光光度法和微波消解法(HNO_3+HF)-ICP-OES时,标准参考物质的铝含量测定结果在标准参考值范围内,这2种方法的加标回收率为86.5%~101.1%;采用微波消解(HNO_3)-ICP-OES法、微波消解(HNO_3)-铬天青S分光光度法与湿法消解(HNO_3+H_2SO_4)-铬天青S分光光度法时,测得普通样品的标准偏差为0.50~4.22 mg/kg,加标回收率为74.3%~99.0%。结论微波消解法(HNO_3+HF)-优化铬天青S分光光度法和微波消解法(HNO_3+HF)-ICP-OES法,均可准确测得总铝含量;微波消解(HNO_3)-ICP-OES法、微波消解(HNO_3)-铬天青S分光光度法与湿法消解(HNO_3+H_2SO_4)-铬天青S分光光度法测得的结果是可溶性铝。

Optimization of technology system for determination of aluminum content in foods

Objective To establish the efficient method for the determination of soluble aluminum and total aluminum in foods. Methods The samples were pretreated by microwave digestion (HNO3, HNO3+H2SO4, HNO3+HF) and wet digestion (HNO3, HNO3+H2SO4), respectively. The aluminum content of standard reference materials and common food samples were determined by chromium azure S spectrophotometry and inductively coupled plasma optical emission spectrometry (ICP-OES). The reliability and accuracy of these methods were verified by recovery tests. Results The determination results of aluminum content in the standard reference material by the microwave digestion method (HNO3+HF)-optimized chromium azure S spectrophotometry and microwave digestion (HNO3+HF)-ICP-OES were within the standard reference range. The recovery rates of the 2 methods were 86.5%-101.1%. The relative standard deviations of common food samples were in range of 0.50-4.22 mg/kg, and the recovery rates were in the range of 74.3%-99.0% by microwave digestion (HNO3)-ICP-OES method, microwave digestion (HNO3)- chromium azure S spectrophotometry and wet digestion (HNO3+H2SO4)- chromium azure S spectrophotometry. Conclusion The total aluminum content can be determined accurately by microwave digestion (HNO3+HF)-optimized chromium azure S spectrophotometry and microwave digestion (HNO3+HF)-ICP-OES. The soluble aluminum content can be determined by microwave digestion (HNO3)-ICP-OES, microwave digestion (HNO3)- chromium azure S spectrophotometry and wet digestion (HNO3+H2SO4)- chromium azure S spectrophotometry.